Ray Kurzweil has responded to my criticisim of futurist fortune-telling. It really just compounds the problems, though, and gullible people who love Ray will think he's answered me, while skeptical people who see through his hocus-pocus will be unimpressed. It's kind of pointless to reply again, but here goes.
His first point is silly.
For starters, I said that we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation within two decades, not one decade, as Myers reports.
I don't care.
I didn't make an issue of his timescale in the first place; in fact, I said it made no difference. The problem is that he has provided no reason to specify a date, other than his vague mantra of "exponential growth". Why not say 5 years? Why not 50? The heart of the Kurzweil method is to simply pick a date far enough in the future that we cannot predict what technological advances will occur, and also far enough forward that he isn't likely to be confronted with his failure by people who remember what he said, and all is good. My complaint isn't that he has set a date by which we'll understand the brain, but that he has provided no baseline value for his exponential growth claim, and has no way to measure how much we know now, how much we need to know, and how rapidly we will acquire that knowledge. "Really fast" or "exponentially increasing" are not informative.
I mentioned the genome in a completely different context. I presented a number of arguments as to why the design of the brain is not as complex as some theorists have advocated. This is to respond to the notion that it would require trillions of lines of code to create a comparable system. The argument from the amount of information in the genome is one of several such arguments. It is not a proposed strategy for accomplishing reverse-engineering. It is an argument from information theory, which Myers obviously does not understand.
I think I understand it better than Kurzweil. If we have a seed of information that initiates a process, followed by many activities and interactions that add progressively more information to the process, you can't use information theory to measure the amount of information in the seed and then announce that you've put an upper bound on the amount of complexity in the process.
For instance, you can't measure the number of transistors in an Intel CPU and then announce, "A-ha! We now understand what a small amount of information is actually required to create all those operating systems and computer games and Microsoft Word, and it is much, much smaller than everyone is assuming." Put it in those terms, and the Kurzweil fanboys would laugh at him; put it in terms of something they don't understand at all, like the development and function of the brain, and they're willing to go along with the pretense that the genome tells us that the whole organism is simpler than they thought.
I presume they understand that if you program a perfect Intel emulator, you don't suddenly get Halo: Reach for free, as an emergent property of the system. You can buy the code and add it to the system, sure, but in this case, we can't run down to GameStop and buy a DVD with the human OS in it and install it on our artificial brain. You're going to have to do the hard work of figuring out how that works and reverse engineering it, as well. And understanding how the processor works is necessary to do that, but not sufficient.
Kurzweil does add another piece to his argument, although it doesn't help: the modularity and repetitive organization of the human brain.
For example, the cerebellum (which has been modeled, simulated and tested) -- the region responsible for part of our skill formation, like catching a fly ball -- contains a module of four types of neurons. That module is repeated about ten billion times. The cortex, a region that only mammals have and that is responsible for our ability to think symbolically and in hierarchies of ideas, also has massive redundancy. It has a basic pattern-recognition module that is considerably more complex than the repeated module in the cerebellum, but that cortex module is repeated about a billion times. There is also information in the interconnections, but there is massive redundancy in the connection pattern as well.
This is true — the cortex is a layered structure with similar elements repeated over and over again, in broad arrays. Pyramidal neurons, for instance, are instantly recognizable and and share a whole suite of common morphological elements between each other — but each one is also as unique as a snowflake. Those differences matter, and they are not specified in the genome. (For that matter, you won't find any blueprint in the genome for the dendrite pattern of pyramidal neurons, either). If you want to recreate a generic human brain, it won't work if you just make every pyramidal neuron exactly identical; there have to be spatial differences and differences in connectivity. You especially won't be able to carry out something far more specific, such as emulate Ray Kurzweil's brain, if you decide to simplify and make his cortex a uniform array of identical modules.
In short, here's Kurzweil's claim: the brain is simpler than we think, and thanks to the accelerating rate of technological change, we will understand it's basic principles of operation completely within a few decades. My counterargument, which he hasn't addressed at all, is that 1) his argument for that simplicity is deeply flawed and irrelevant, 2) he has made no quantifiable argument about how much we know about the brain right now, and I argue that we've only scratched the surface in the last several decades of research, 3) "exponential" is not a magic word that solves all problems (if I put a penny in the bank today, it does not mean I will have a million dollars in my retirement fund in 20 years), and 4) Kurzweil has provided no explanation for how we'll be 'reverse engineering' the human brain. He's now at least clearly stating that decoding the genome does not generate the necessary information — it's just an argument that the brain isn't as complex as we thought, which I've already said is bogus — but left dangling is the question of methodology. I suggest that we need to have a combined strategy of digging into the brain from the perspectives of physiology, molecular biology, genetics, and development, and in all of those fields I see a long hard slog ahead. I also don't see that noisemakers like Kurzweil, who know nothing of those fields, will be making any contribution at all.
So what exactly is the basis of Kurzweil's expected magic great leap forward? And no, the miracle of exponential growth is not an answer. If all a futurist has to do is wave his hands and say things will change more rapidly than we expect, then futurists like Kurzweil are nothing but techno-gimmicky Criswells. Utterly useless.









Comments
Posted by: coel.hellier
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August 21, 2010 11:19 AM
Isn't a more basic fundamental that "basic principles of operation" is a fairly undefined goal? You could argue that we understand that now, at a basic-enough level.
Posted by: Glen Davidson
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August 21, 2010 11:31 AM
He doesn't understand how complex and information-rich the development process is, and certainly has no clue as to how to mimic or to compensate for the highly complex biological and environmental factors affecting brain development.
Who knows how much we'll understand in 20 years? It took a long time for us to even get to a fairly good understanding of a mere protein folding, while the brain is almost infinitely more complex than is protein folding.
Glen Davidson
Posted by: Chuck
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August 21, 2010 11:31 AM
Time is apparently Kurzweil's god.
Did I just quote Kent Hovind?
Chuck
http://www.irreligiosophy.com
Posted by: theswede
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August 21, 2010 11:43 AM
What I find most astonishing about these predictions is that today, on computer systems of a power which was unimaginable a mere two, three decades ago, we're using a system which first saw the light of day in 1968.
And we haven't gotten any further at all since then. Skype? They had a functional equivalent. A Window based OS? Yep. Co-operative work on the same document in real time, something we still have problems with? Yep.
With all this exponential growth, we're finally reaching where we were 40+ years ago. And this is why it's so incredibly naive to assume that just because we get more, faster transistors we suddenly will be able to do such amazing things without learning how to actually do these amazing things.
For the interested, the demo of the system is here:
http://sloan.stanford.edu/mousesite/1968Demo.html
Posted by: glenister_m
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August 21, 2010 11:45 AM
I wonder if he is confused between reverse engineering the brain (trying to duplicate the brain with a computer), and simulating the brain (extension of the Turing Test that would also take input from sensors like cameras, microphones, etc.).
Since we already have programs that have fooled the occasional person in Turing Test trials, and they are working on programs to simulate a person's interactions with a given environment, that in 10-20 years we might have an interactive program that for all practical purposes simulates a person/brain.
However that would not be duplicating the brain any more than a chess program duplicates the thinking processes of a chess master.
Posted by: JD
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August 21, 2010 11:46 AM
...unless Henry Markram is working on a keyboard solo to accompany Kurzweil's exponential "Jump."
Posted by: catofmanyfaces
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August 21, 2010 11:49 AM
I think the basic problem that so many make when talking about the brain is that they don't understand that the brain is a bunch of neurons in a big chemical soup.
To model it right we need to be able to model the soup as much as we need to model the neurons. It's all so much more messy than most people realize.
Posted by: Graves
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August 21, 2010 11:50 AM
I agree completely that Kurzweil is off his rocker. I am a bit confused by what you say about pyramidal neurons, though. You say that the differences between them that make each unique are not specified in the genome. I imagine you are emphasizing that they emerge through the unfolding of development, but that really does not mean they aren't specified in the genome. Just because physical rules and the environment are major factors in the end organism does not mean traits aren't specified in the genome. If we take that stringent stance very little at all will be specified by the genome, because we know strong environmental perturbations will change essentially all traits. Maybe I am misreading you, though.
Posted by: Joe Fatzen
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August 21, 2010 11:52 AM
You talk about what you do not know...!
Halo: Reach is programmed for the Xbox 360, which runs on IBM's Power PC CPUs, not Intel processors!
Therefore everything Kurzweil says is correct!!
Posted by: Steven Dunlap
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August 21, 2010 11:59 AM
Kurzweil (and lots of others) in going ga ga over technological developments gives technology some sort of magical hoo-doo voodoo sort of capabilities that it clearly does not have. The results of hi-tech devices requires a human brain to interpret them and the results do not necessarily give us as much information as we might like to think.
For a concrete example, researchers are only recently subjecting functional MRI research to falsification. Researchers at Dartmouth put a "test subject" in an MRI then showed the "test subject" a series of photographs which have been used in a functional MRI test to determine the brain's reactions to emotionally charged vs. emotionally neutral images. The "test subject's" brain lit up for each picture. Who was the "test subject," you might ask? A dead salmon.
Posted by: Kawa
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August 21, 2010 12:00 PM
Doc? Your inner hacker's showing. :)
Posted by: Andyo
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August 21, 2010 12:05 PM
Coming from a layman's perspective, I wonder how freaking stubborn (dare I say, fundamentalist) do all these Kurzweil fans have to be, when pretty much everyone who knows biology and the brain are telling them they're wrong. And just as the fundamentalists, they bring up one or two "biology" names that according to them support their theories and think they're vindicated.
I'm pretty sure the Galileo gambit also popped up there, and in the later posts there was some dumbass doing old quotes from "skeptics" about computers which were proven wrong with time.
Posted by: Standard Curve
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August 21, 2010 12:11 PM
Posts like this are fantastic. Not only do I get the entertainment value of seeing a kooky futurist methodically beaten down, but I gain a much better understanding of the complexity of life than I previously had.
Posted by: setad7
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August 21, 2010 12:17 PM
This was great! I'd love to see you go after the Cryonics madness, that seem to be all the rage in trans-humanist circles.
Posted by: Pareidolius
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August 21, 2010 12:19 PM
Well, PZ, we shall see . . . in the FUTURE! For that is where we all shall live!
Criswell . . . heh.
Posted by: Zzarchov
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August 21, 2010 12:20 PM
Well I guess it depends on how many people you are willing to murder and dice up for testing purposes.
To go with your "number of transistors" analogy (and I don't understand biology, so I am just going off of technology and this may not apply AT ALL to biologgy). If you know the number of transistors and how they are arranged in all its complexity (even without understanding why) you could build a replica machine. You could then take the information from another machine (with halo reach) and clone it over, having two copies.
I imagine to get that information from a brain would require quite a bit of murdering and trial and error until you get it right.
I hope he doesn't plan on forming unit 731b or working for Dr.Mengele Jr.
Posted by: Aliasalpha
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August 21, 2010 12:20 PM
From my years in IT, I've come to classify users into 3 parent classes
1) IT Professionals who know "everything" (IE: What they need to know to do their jobs and computer problem solving but still don't know how computers really work, thats for computer scientists)
2) Competent Users who know what they need to to do their jobs and when in doubt, they call helpdesk
3) Incompetent Users who's reactions to computers could best be described as "OOOH MAGIC BOX! I'm afraid, to touch it but OOH LOOK A VIDEO OF A CUTE KITTY!!! STAY AWAY FROM MY MOUSE CUTE KITTY! HAHAHA". Responsible for 90% of the virus, spyware and malware infections (and 99% of the helpdesk stress related suicides/homicides), voted most likely to respond to exiled nigerian princes and firmly convinced that the machine really is magic and can do anything.
I have a sneaking suspicion which class Kurzweil belongs in.
Posted by: ralphgentile3
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August 21, 2010 12:24 PM
I predict mail will be delivered to my house today at XX:XX o'clock, and the Universe will cease to exist sometime in the next gajillion years.
Posted by: Zzarchov
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August 21, 2010 12:24 PM
@Aliasalpha
You forgot one: The failed computer science who either "fell from grace" due to financial and perosnal issues, or never made it due to EXCEPTIONALLY poor social skills. Either way they are bitter and petty about it.
Posted by: Pareidolius
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August 21, 2010 12:27 PM
In the interest of accuracy (that, and I don't want to get dogpiled for my Criswell paraphrasing), here is the actual quote which is even more germane . . .
Pure Plan 9.
Posted by: drbunsen
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August 21, 2010 12:37 PM
Best. Summary. Ever.
Posted by: Zeno
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August 21, 2010 12:38 PM
John Horton Conway and his collaborators demonstrated decades ago that amazing complexity can arise from an extremely parsimonious set of simple rules. Martin Gardner brought this to our attention when he published his first Scientific American column on Conway's game of Life, the two-state cellular automaton that was soon shown to be universal (capable of instantiating a universal Turing machine).
Such power indicates that Conway's Life will eventually evolve to take over the universe. It's only a matter of time.
Posted by: grudgedk
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August 21, 2010 12:45 PM
And it's an utter logical fallacy. It's like saying that there is no difference in the amount of information required to build a soda can, or a 747 fuselage. One simply contains more Aluminium than the other. The whole point people were making was that the Genome is not a blueprint, so it is an insufficient as any form of measure as to the resulting complexity of the brain, in much the same way as knowing the temperature, and amount of water molecules, is in no way an indication of how any given snowflake is going to end up.Posted by: raven
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August 21, 2010 12:47 PM
Maybe not. Kurzweil's problem seem to be that he is afraid of dying or wants to live much longer.
Don't blame him, some sort of life extension sounds good to me.
People deal with it in various ways. Magical wishful thinking known as religion is common. Kurzweil is putting his faith so to speak in technology.
Something like that may even be possible someday but his timeline seems to be off. Everything takes longer and costs more than people expect as we've seen with our two current wars. Cheney claimed that the Iraq fiasco would pay for itself because the Iraqi's would be so grateful to the allies they would pump lots of oil.
Posted by: eleusis
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August 21, 2010 12:49 PM
I'm really getting tired of comp sci geeks / Kurzweil fanboys spouting off about the brain. Kurzweil should go back to selling his $1200 alkaline water filter scam.
Posted by: robert.rayborn
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August 21, 2010 12:59 PM
PZ and others,
Kurzweil aside, I would be very interested in what you have to say about Jeff Hawkins models of the neocortex. I am a CS major, not a biologist, so I would appreciate your opinion. If nothing else, his models do learn quite effectively (better than traditional machine learning techniques), although this by no means proves that he is correct in his assumptions.
Posted by: nejishiki
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August 21, 2010 1:00 PM
There is another interesting criticism of this kind of work: the more you understand about an object (e.g. the brain), the less relevant a model of it becomes:
In this view, a model of the brain would simply be a stepping stone on our way to true knowledge. The only other reason I can think of for wanting a future of 'human brains in computers' is that you think this kind of AI will be useful. I don't see why. Generally, we build tools that make up for our shortcomings, not duplicate them. We build planes because we can't fly, bulldozers to lift what we can't, etc. Why would we need more simulated human brains, if we already understood them well enough to build a model of one? We need technology to do the things we can't do.Posted by: Miles670
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August 21, 2010 1:03 PM
I do enjoy these responses. Some parts i had to read twice to understand, but still.
Posted by: 'Tis Himself, Quel Dommage
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August 21, 2010 1:03 PM
Zzarchov #19
Aren't these the folks who run the help desk?
Posted by: James Quin
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August 21, 2010 1:06 PM
Mr. Myers,
Do you think AI scientists will ever develop an AGI equivalent to a human intellect or beyond?
Sincerely,
James Quin
Posted by: mythwrangler
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August 21, 2010 1:09 PM
Ray is assuming that everything necessary for a brain to function can be derived from the hardware (wet?). But there are lots of reasons to think this is not true. Perhaps one can infer the nature of the software from the structure, but he gives no compelling (or any) argument as to why this might be the case. Essentially his answer to the mind/brain problem is "=brain". He might be right, that if you get the structure sorted out everything else will fall into place. It seems unlikely tho. I'm tempted to say that a behaviorist approach is better, but I have no more basis for this stance than he does for his.
Posted by: https://me.yahoo.com/a/S5prevQVie1EfQXER5NMFxrrHTRG#fff61
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August 21, 2010 1:10 PM
Dear PZ,
While I do think that Kurzweil's optimism is on very shaky grounds, your criticism is on as shaky grounds.
Whatever it is that you mean here by "baseline value" - he has provided the exponential curve http://en.wikipedia.org/wiki/File:PPTSuperComputersPRINT.jpg
Whether or not you agree that the exponential is going to hold or with his estimate of computational power required to get a working brain simulation is a different issue. Yes, as others pointed out the estimate ignores the chemical soup and only takes into account (basic) neuron interaction, but they fail to show that the soup is indeed necessary for simulating intelligence. Given all the progress in various types of ANN's, it's a reasonable null hypothesis to assume that none of that stuff has a major contribution.
The analogy to Halo Reach is completely befuddling me. It's so similar to some creationist "analogies" that it's really weird coming from you. Ray's argument was about initial complexity of the brain neuron pattern, the rest is learning (again, this ignores random individual variations, which are unlikely to have a major contribution, as well as the soup). So yeah, the blank slate of an Intel chip has little complexity, and Halo Reach is very complex, but what in gods' name does this have to do with how our programs in the brain are learned? Take the blank slate, insert it in a body and let it go. Quite unfortunately Xbox games are not produced in such a fashion.
To emphasize one more time - yes, his estimates rely on a lot of assumptions - the main ones being that the exponential growth will continue long enough and that minor variations and weak interactions are irrelevant for the big picture. But representing it as incoherent as you seem to imply is incorrect.
Best,
Ed
Posted by: ogremkv
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August 21, 2010 1:10 PM
I think Kurzweil is getting confused. I think he must have read the article that says the estimate of computing power will equal the human brain (in a super computer) in about 15 years. While the same computing power will be available in a desktop in about 30 years.
Not withstanding quantum computers or other unknown tech advances.
Note that isn't the same as being a brain... just equivalent computing power.
Posted by: daedalus4u
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August 21, 2010 1:17 PM
For those who keep talking about the "unimaginable" progress that has been made in computing; it was never unimaginable.
Turing showed that there were limits to what was computable.
Has anything that Turing showed was not computable been computed using "modern" computers? How long will Moore's Law have to run before what Turing imagined could not be computed will be computable?
Posted by: eleusis
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August 21, 2010 1:24 PM
Kurzweil's scam du jour is overcharging for mega-supplements that are supposed to improve / maintain health. He's no different than the people charging outrageous prices for acai berries, which also have not been proven in any clinical trials to improve health.
Posted by: mitsu.hadeishi
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August 21, 2010 1:26 PM
Okay, let's try to get something clear here:
"I think I understand it better than Kurzweil. If we have a seed of information that initiates a process, followed by many activities and interactions that add progressively more information to the process, you can't use information theory to measure the amount of information in the seed and then announce that you've put an upper bound on the amount of complexity in the process."
Again, the point, as I understood Kurzweil, was simply trying to get an upper bound on the Kolmogorov complexity of the algorithm needed to generate the *brain* --- which is totally different from the Kolmogorov complexity of what one might loosely call the "software that you'd run on the brain", or human behavior. It's obviously correct that what the brain is capable of doing (in terms of its behavior) is far, far more complex than the algorithm that might be necessary to simply generate the brain structure itself.
So yes, of course you are right that generating an Intel CPU is not the same as generating Halo or OS X or whatever else --- they're quite separate things. However, I don't see that Kurzweil is making the claim that once you had a system that was as complex as the brain you would then have AI. My belief is that he may be right that we could potentially build systems with the same computational power as a brain within our lifetimes --- but he's probably very wrong that we'll get anything like human-level AI in our lifetimes, though I can't say for certain he's wrong.
I mean, think about what we do with computers today, despite the fact that they're immensely faster and more powerful than the computers of 10, 15, 20 years ago: we still mostly type into them and read text. It's hardly the massive leap forward one would hope for, because the advances in software are far behind advances in hardware. So yes, you're right I think in your criticism but this doesn't invalidate the simple claim that the upper bound of the algorithmic entropy of the brain may be roughly the size of the genome. That argument can be correct and yet not say that much about how to generate AI.
Posted by: Matt Warren
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August 21, 2010 1:28 PM
These comments pretty much echo my own sentiments. While I applaud the enthusiasm to which high-technology advocates have for the cool tools our species has developed, I can't help but feeling that Kurzweil's thoughts can be summed up in two words:
Secular Afterlife
Posted by: nejishiki
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August 21, 2010 1:31 PM
#34
if you're talking about Turing's work "On computable numbers, with an application to the Entscheidungsproblem," i.e. his version of Godel's theorem that introduced the Turing Machine, then no, computers still can't compute some things. This is a permanent, logical hurdle, not a practical one, and it should apply to the brain as well: the brain will face the same kinds of limits as a Turing Machine. There is no indication that this hurdle will be overcome - or, however, that it is relevant to the study of the brain.
Posted by: Gregory Greenwood
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August 21, 2010 1:32 PM
So, PZ is a fan of Halo, mayhap? Could it be that, beneath his reflective helmet, the Master Chief is no other than PZ? Mild-mannered (well, ish) blogger and biology professor by day, super-soldier champion of humanity and fearless defender of rationality against the psychotic hordes of alien fundies by night...
Posted by: Marco
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August 21, 2010 1:34 PM
According to the Newsweek review, Byrne maintains that we must be "nice to water", because if we are not, then water turns nasty on us, or something like that.
Apparently, this is all the more urgent and necessary because “the inside of your head is 80 percent water”.
I understand the depth of her concern, because, probably, the inside of her head and that of a great majority of her readers is 100% water as well.
Posted by: llanitedave
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August 21, 2010 1:36 PM
For centuries, mankind dreamed of emulating the flight of birds. Numerous very bright people made detailed studies. The process turned out to be incredibly complex, so complex in fact, that we still haven't succeeded in accurately modeling or simulating bird flight.
But we didn't need to. We found much simpler ways to fly higher and faster with more cargo than any bird could ever have approached.
Same with the brain emulation. It would be nice to know how the human brain works, and attempts to model it are worthwhile. But what are we trying to accomplish? We already have machines that can do math far better than we can, and that can analyze the properties of materials, or assemble tiny components.
Are we looking for a machine that can gossip and adopt superstitions? Or one that can be depressed or act like a megalomaniac?
As for pure logical reasoning power, we don't need to emulate the brain to get that. If our goal is to take input from the environment and solve general-purpose problems requiring intelligent analysis, including learning, well we may indeed do that within 50 years, better than the human brain will.
But it won't happen from trying to model the structural and biological details of the human brain. We'll do it by taking advantage of the unique properties of the materials we're able to manufacture and the unforeseen opportunities that they give us.
And if implantable "brain enhancement chips" ever become available, we'll definitely need to know enough about the brain to create a seamless interface, but the chip will not need to be the same type of circuitry as the brain. It can still be a black box as far as brain systems are concerned.
Posted by: Marco
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August 21, 2010 1:37 PM
Oops, I posted my message (#40) in the wrong thread. My apologies.
Posted by: Greylander
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August 21, 2010 1:39 PM
PZ:
Despite my defense of Kurzweil in your last post, I have barely read anything he's written. So I'm not going to offer what I think his particular reasoning might be for the particular date.
From everything I've seen you say, I suspect that you think 50 years is just as ridiculous as 20 and that you would put the estimate, if you made any estimate at all, well beyond 100 years. Why are you asking Kurzweil to justify a distinction of a factor of 2 or 3 in the timeframe, rather than to justify order-of-magnitude?
My own "error bars", "95% confidence", on my own estimate are about as large as the range you specify. For me 20 is a nice round number that lies in roughly the middle of my range on a logarithmic scale. I'd give 20:1 odds on the the range 5 to 50 years.
Why don't you ask Kurzweil what range of years he will give 20:1 odds on? Maybe make a gentleman's bet?
What range of years would you give 20:1 odds on? If it is a long long time... you can bequeath the proceeds to your estate.
I think that is a good question for everyone here. Choose one or both of the following:
What is the smallest range of years that you would be willing to offer the bet of $20 to your opponent's $1 that "reverse engineering of the cerebral cortex" *will* occur in that time frame.
-OR-
What is the widest range of years for which you would accept the bet at $1 to yoru opponent's $20?
PZ:
For instance, you can't measure the number of transistors in an Intel CPU and then announce, "A-ha! We now understand what a small amount of information is actually required to create all those operating systems and computer games and Microsoft Word, and it is much, much smaller than everyone is assuming." Put it in those terms, and the Kurzweil fanboys would laugh at him; put it in terms of something they don't understand at all, like the development and function of the brain, and they're willing to go along with the pretense that the genome tells us that the whole organism is simpler than they thought.
What complete and utter crap.
PZ, your analogy is completely and utterly wrong. And again it shows you have no clue about the information theoretic argument being made.
Counting the number of transistors in a CPU would give you a measure (upper bound) on the information content of the hardware only, not the information content of whatever software you might happen to load. No one is making an equivalent contention for squishy biological wetware.
The correct analogy is
hardware fundamental stuctures & processes
software& data detailed and highly plastic wiring of the brain
Kurzweil and I both contend that the information content of the "hardware" is coded in the genome. I know that you still dispute even this. But at least represent our position correctly. Your analogy is way off-base.
I think a big part of the disagreement here is that because the brain codes information by physical changes to the wiring, PZbots just can't wrap their heads around calling that software. "Wiring" just sounds too much like hardware in your minds.
Posted by: Nerd of Redhead, OM
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August 21, 2010 1:46 PM
And there you make your fatal mistake. The directions for building the wetware are there, but the actual wetware is built by a sloppy builder who only looks every so often at the blueprints, and the directions and keep changing due to environmental factors. Any correlation between the "exact" blueprints the final design is purely coincidental, other than it appears to work. Which is what we scientists have been telling you all along, and which you evade by every solipsism imaginable. You are WRONG.Posted by: Greylander
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August 21, 2010 1:49 PM
[fixed blockquotes]
PZ:
Despite my defense of Kurzweil in your last post, I have barely read anything he's written. So I'm not going to offer what I think his particular reasoning might be for the particular date.
From everything I've seen you say, I suspect that you think 50 years is just as ridiculous as 20 and that you would put the estimate, if you made any estimate at all, well beyond 100 years. Why are you asking Kurzweil to justify a distinction of a factor of 2 or 3 in the timeframe, rather than to justify order-of-magnitude?
My own "error bars", "95% confidence", on my own estimate are about as large as the range you specify. For me 20 is a nice round number that lies in roughly the middle of my range on a logarithmic scale. I'd give 20:1 odds on the the range 5 to 50 years.
Why don't you ask Kurzweil what range of years he will give 20:1 odds on? Maybe make a gentleman's bet?
What range of years would you give 20:1 odds on? If it is a long long time... you can bequeath the proceeds to your estate.
I think that is a good question for everyone here. Choose one or both of the following:
What is the smallest range of years that you would be willing to offer the bet of $20 to your opponent's $1 that "reverse engineering of the cerebral cortex" *will* occur in that time frame.
-OR-
What is the widest range of years for which you would accept the bet at $1 to yoru opponent's $20?
PZ:
What complete and utter crap.
PZ, your analogy is completely and utterly wrong. And again it shows you have no clue about the information theoretic argument being made.
Counting the number of transistors in a CPU would give you a measure (upper bound) on the information content of the hardware only, not the information content of whatever software you might happen to load. No one is making an equivalent contention for squishy biological wetware.
The correct analogy is
hardware fundamental stuctures & processes
software& data detailed and highly plastic wiring of the brain
Kurzweil and I both contend that the information content of the "hardware" is coded in the genome. I know that you still dispute even this. But at least represent our position correctly. Your analogy is way off-base.
I think a big part of the disagreement here is that because the brain codes information by physical changes to the wiring, PZbots just can't wrap their heads around calling that software. "Wiring" just sounds too much like hardware in your minds.
Posted by: https://me.yahoo.com/a/S5prevQVie1EfQXER5NMFxrrHTRG#fff61
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August 21, 2010 1:53 PM
#44: adding randomness from the environment does not add information
Posted by: msironen
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August 21, 2010 1:54 PM
I presume they understand that if you program a perfect Intel emulator, you don't suddenly get Halo: Reach for free, as an emergent property of the system.
This is also a complete misrepresentation of the state of the art of AI research (and I dare assume Kurzweil's position). "Emergence" is a weasel-word-popularization that has long since lived its usefulness (if there ever was any) in any circles where people actually know what they're talking about; the idea that building a complex enough computer we get intelligence is basically the same as building a large enough hummingbird facsimile made out of cast iron will get us a flying machine.
Posted by: Form&Function
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August 21, 2010 2:03 PM
Greylander, I'm not sure I understand your correction to PZ's analogy. In terms of the brain, what are "fundamental structures and processes"? Is a cell a fundamental structure, or is it wiring? Because even a cell isn't "coded for in the genome". If the "wiring" of the brain is software, what is neural activity?
Posted by: Greylander
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August 21, 2010 2:03 PM
PZ:
This is true — the cortex is a layered structure with similar elements repeated over and over again, in broad arrays. Pyramidal neurons, for instance, are instantly recognizable and and share a whole suite of common morphological elements between each other — but each one is also as unique as a snowflake. Those differences matter...
More stupidity, (or deliberate misrepresentation).
All those differences that make those "snowflakes" unique are encoding the software of the brain. The hardware is the overall pattern of redundant structures, and the rules governing how those structure self-modify to encode new (learned) information thereby become "unique snowflakes".
I know you've been reading the comments in the previous thread... so I know you should understand this already. But here you go putting up another straw man.
PZ, you are either truly unable to comprehend (very sad)... or else you are a deliberate troll in your own blog (also very sad... but hey, traffic does drive revenue, yes?)
Posted by: Stephen Wells
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August 21, 2010 2:11 PM
The genome on its own doesn't do anything. It has to be transcribed. What gets transcribed depends on the current state of the cell.
Now, Greylander, if you can establish that the state of a just-fertilised egg depends solely on the genome contained in that egg- then you might have a point.
Otherwise, no. There is information in the system that isn't in the genome, ergo the information content of the genome doesn't limit the information in the system, and we're done.
Whoever just claimed @46 that "adding randomness from the environment doesn't add information" desparately needs some remedial education.
Posted by: eleusis
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August 21, 2010 2:15 PM
#10 Steven Dunlap:
Do you have a reference for that study?
Posted by: mitsu.hadeishi
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August 21, 2010 2:16 PM
I really don't understand the point of all the vitriol in this thread. Admittedly I didn't bother reading the other massive thread of comments but just skimming over some of the comments here it just seems totally out of place.
I believe and I argued in the other topic that PZ misread Kurzweil's argument and I think he's still conflating things a bit in this post (though less so). PZ, above, is throwing around some imprecise terms, such as "information content" which is really a totally different, orthogonal notion than algorithmic entropy of Kolmogorov complexity which is the thing Kurzweil is referring to. The picture of "information content getting added" is really not directly relevant to the Kolmogorov argument regarding the algorithmic entropy of the basic structure of the brain. As an algorithm unfolds it may well generate all sorts of complex structures and behavior but this doesn't really change the initial conditions.
But again, PZ is *correct* that merely generating a brain, even if Kurzweil and Sejnowski are correct that the genome is a rough upper bound of the algorithmic complexity needed to generate the brain, would not, of course, generate human-level AI. That would of course require actually running this "brain" in interaction with its environment for a long time, so it can learn and so forth. What Kurzweil is clearly referring to, however, is just the raw brain itself, untrained and without having learned anything via interaction with its environment.
There's another thing left out of Kurzweil's argument, which is that merely determining an upper bound of the algorithmic complexity of an algorithm needed to generate the brain doesn't say much about FINDING an algorithm that could generate brain-level behavior. Our brain in the result of billions of years of evolution. Clearly, an algorithmic "brain" would be totally different in structure, but even if one could in principle find a algorithm capable of generating a brain-like entity, this doesn't say much at all about the ability to actually find such an algorithm. It could take millenia or millions or billions of years to find it. Not at all easy, even if Kurzweil's argument is correct. The exponential increase in hardware power doesn't eclipse the difficulty in searching the even more vast exponential space of all possible algorithms.
I really think these sorts of debates ought not be held in an atmosphere of vitriol. That's for politics (which seems to be increasingly based on demagoguery). This should be a rational discussion, not some ridiculous flame war.
Posted by: co
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August 21, 2010 2:18 PM
Nerd @ #44:
Bingo. Nice way of putting it.
Posted by: Nerd of Redhead, OM
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August 21, 2010 2:19 PM
Your concern is noted and rejected. I recommend the Intersection, where how you argue is more important than the information transmitted. Begone oh one of concern...Posted by: mitsu.hadeishi
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August 21, 2010 2:24 PM
Whether you "reject" my concern or not, it remains the case that most of the comments in this thread so far are talking past each other because you're just entrenching yourself in emotional vitriol. Both sides are making various errors, subtle and gross, and unable to really see the source of the disagreement is amplified based on a lack of understand of each other's terminology and a lack of understanding of the principles of each other's fields. But, if you enjoy spending your time this way, by all means, have at it.
Posted by: theswede
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August 21, 2010 2:24 PM
@36: Again, the point, as I understood Kurzweil, was simply trying to get an upper bound on the Kolmogorov complexity of the algorithm needed to generate the *brain*
And again, doing it this way is BOGUS.
To analogize; if RK claimed that the upper bound of a known to be immensely complex function is the compressed size of the rather small argument passed into it, would you consider that a persuasive argument? Would it be some form of argument worth putting forth, even?
The *brain* is generated by the environment the genome operates inside, starting with the cygote, continuing through the womb and the growing body, and taking its final steps inside the functional body as it feeds on sensory input.
Of the *brain*. Not the mind. Not the "software" which "runs" on it. The brain itself is built this way (although I have simplified the process to the point of incorrectness).
This is why any argument that the complexity of building a *brain* can be found by compressing the genome is sheer ignorance at best, stupidity at worst.
Posted by: Efogoto
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August 21, 2010 2:25 PM
Kurzweil could have been a story guy for Hanna Barbera working on the Jetsons. "There'll be flying cars and robots for everybody!"
Posted by: https://me.yahoo.com/a/O.jullMj0I2VvJaxMMVeNKSfOPf73voLSxJAe9PdlOWwi8Y-#258ec
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August 21, 2010 2:28 PM
our brains structure is very plastic and changes over time and activity as I understand so that the brain as "designed" by the genome is not the same at birth or at other times subsequent. The development depends of stimulation and learning which seem to be very much time age dependent.
The interconnections of the neurons can and do change over time. I think one of the mistakes that scientists and other people who are not trained in biology make is thinking of things and not processes. Life is not a thing. A thing is an abstraction that helps facilitate thought.
If and when someone makes a "electronic replica" of a brain it will be just as much dead meat as any brain in the butcher shop and just as useful .. unless we understand and replicate the plasticity of the process of brain.
see
http://en.wikipedia.org/wiki/The_Treachery_of_Images
the "thing" as brain AI is a representation of a something that is dependent on the material that is made of and all of that but is experienced and acts as a process
Posted by: mitsu.hadeishi
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August 21, 2010 2:30 PM
>the rather small argument
It's really not that bogus. Of course as the zygote develops all sorts of environmental interactions occur. But the fact is, embryos can grow in vitro for a while without the environment of the mother. Obviously they would die without being transplanted into the womb, but I think it's at least plausible to suggest that the amount of additional algorithmic entropy contributed by the environment of the womb, etc., is relatively small. One could imagine, in theory, someday being able to grow brains or embryos in some sort of artificial womb environment, for example. And note that the womb itself is made up of an organisms whose blueprint is also the genome.
The point of Kurzweil's argument is a back of the envelope guesstimate of Kolmogorov complexity. Obviously it leaves out a lot of detail but even if it's off by an order of magnitude or so it is nevertheless a plausible argument. I'm simply saying that the question of whether one could actually build a simulator is separate, as is the question of whether one could build an AI even if in principle one could find an algorithm that might run on some supercomputer that could generate the brain structure.
Posted by: https://me.yahoo.com/a/S5prevQVie1EfQXER5NMFxrrHTRG#fff61
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August 21, 2010 2:34 PM
Do provide that education if you will. I'm giddy with excitement to learn how adding randomness (shall I say noise, to make it easier for comprehension?) is going to add information. Maybe you're thinking of describing the specific random state, which does indeed require more information, but guess what - it's far easier to just put a random generator instead (unless for some unknown reason you want to copy the specific random state - pretty irrelevant for discussion of creating a blank brain).
Posted by: Dm5171
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August 21, 2010 2:34 PM
I agree with Ed and Greylander: PZ doesn't really understand what Kurzweil is saying. That doesn't mean Kurzweil is right about everything he says, or even such wild predictions as having machines where you can "upload" your brain in 20 years. Like PZ, I consider such timelines irrelevant.
The question is, WHAT is the point Kurzweil is making about information complexity in brain? I don't think PZ has a clue, because his weird analogy about Intel CPUs and Halo make absolutely no sense. Greylander explained it well, let me try to make it even easier to understand, if I can.
First, let's get away from the adult brain, with all its learning and wiring, and talk only about a baby's brain. Kurzweil means something closer to this, a brain which contains no learning, upon which you can impress your own knowledge (upload your brain).
In case of the human brain, much of this knowledge is exactly in the form that PZ mentions - the brain constantly rewires itself, adjusts the number of strengths of the connections, reinforces certain connections while attenuating others. Mechanisms such as long term potentiation of glutamate receptors in memory are examples of this. There are many more.
From the computer science perspective, this is all software. In the very old days, computers were actually programmed by rewiring them. For example, you acquire skills - you can add numbers or multiply them, which you couldn't do when you were born. Something physical has changed in your brain to enable this, just like something physical changed in a computer. In the case of the computer, the change was that your math program loaded into memory. In case of the brain, this might involve setting up new connections, modifying old ones. The difference is that in the brain the changes can be STRUCTURAL too, which is something we deliberately avoid with computers. We want computers to be able to wipe a program completely from memory, to install a new one. This is why we moved away from rewiring computers to program them, like we did originally.
The point remains, this is all LEARNING, stuff you do AFTER you're past the baby brain stage which Kurzweil is talking about. If you implement an AI in silicon, obviously your methods of programming it will be different than in biology. But it is programming nevertheless.
Kurzweil is ONLY talking about what it takes to produce a human brain CAPABLE of one day being an adult. In biological terms, he is talking about going from a zygote to a new born, NOT an adult. He says that the instructions for doing that are coded in the zygote's DNA. Now, from a biological perspective, this is not strictly true. The zygote's DNA uses the machinery of the cell to read the DNA and follow its instructions. Obviously, a computer will need machinery to do the same thing, and just as obviously, the computer's method will not be the same as biology. Also, there are factors such as the maternal hormonal environment, various triggers that affect the baby's development in the womb. We don't know how much information the ebb and flow of hormones add to the process. From what I have read it's not like 10x more than the information in the DNA itself, it's within an order of magnitude, which is all Kurzweil is saying. Also remember that the zygote's DNA contains a ton of information which is irrelevant to us, such as how to produce liver cells or muscle proteins, or pigments, or any number of such things which we don't care to simulate. Or how to produce the enzymes needed for energy production, energy distribution and consumption. In the computer's case we just plug it in and don't worry that this process adds extra information about how energy is produced at a utility. We just spec the silicon, and don't worry about adding information about the fab that made the chips.
In short, a computer's information "density" is much higher than just the program it runs and the hardware it runs on, it actually includes manufacturing, energy needs, etc. Stuff that we ARE counting in DNA, because DNA actually codes for it.
Kurzweil's calculation roughly shows the magnitude of complexity of the new-born's brain. Very roughly. He bases his calculation on the information content of DNA. We know that this isn't 100% correct, but I have seen no argument to show why it's 10 orders of magnitude off, or some such fantastic number.
I see arguments like PZ pointing out that not all pyramidal neurons are the same, they're different, and their difference codes information! Well, duh. Of course it does. Kurzweil's point is that this difference IS the program, the stuff that constantly changes throughout life as you learn new skills and forget old ones, as you acquire new memories, etc. Even the simplest neural net simulations which treat whole neurons simplistically as nodes include this feature - the neurons are NOT identical. This is precisely how they learn too - by making new connections, by changing the weights of old ones. This is CS 101, we've been doing it for ages.
Modern neuronal simulations are much more complex, including modeling the dendritic structure, synapses, neurotransmitter-receptor interactions, enzyme kinetics in the synaptic cleft, neurotransmitter release and uptake, etc. Just do a search on pubmed and see what people are actually doing these days.
Even this is besides the point. As Kurzweil says, he is NOT talking about reverse engineering the brain from proteins through neurons through complex dendritic branching through actual networks. This task would be formidable, and it may be centuries before we understand the brain well enough to do it. He says he only mentioned this to talk about information content of the HARDWARE, which to him, means something like a baby's brain.
As for how we will get there since reverse engineering in this fashion is impossible, he offers some examples from the neuronal units in the cerebellum and the frontal cortex. You could cite more in the visual cortex, where the pattern of such microunits of neurons is also very regular. He's saying that THIS sort of work is what might lead to AI. He's not alone in this. There are hundreds of neuroscientists with PhDs working on exactly such approaches. Whether they will succeed in 20 years or not, who knows. PZ says he doesn't care about that, and neither do I.
Finally, although I don't like Kurzweil much myself, I'd like to say that if you want to call someone a fraud (which is what comparing him to Deepak Chopra means), at least take the trouble to read his own words. Why rely on 3rd hand reporting from Gawker, which isn't even a science magazine. It's trash written to generate fast page hits.
Posted by: Greylander
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August 21, 2010 2:34 PM
@ #48 Form&Function:
Thanks for asking good honest question(s). Neural activity is *also* software -- much faster software, if you like to think of it that way.
If you mean that "any particular neuron, of any particular type at any particular [x,y,z] coordinate was not directly coded for in the genome", that is true. The genome is not a blueprint, it does not include a listing of each individual cell and the coordinates for that cell in the body. But this does not alter the information theoretic argument one iota. No such claim is made.
Have you ever looked at a fractal image...? intricate, beautiful, complex... apparently, dare I say, information rich. Yet that fractal image, with millions of pixels -- millions of byts of data -- is generated by a simple, tiny program only a few bytes long. Which means the whole fractal image actually only has a few bytes of information content. Yet the fact than any particular pixel at any particular location has any particular color is not in any direct way "coded for in the fractal generating program".
Is the neuron coded for in the genome? Not directly. Does the genome govern the process by which a certain rough patterns and distributions of neurons is grow in the brain? Yes. Is there randomness in the exact locations of the neurons not coded for in the genome? Yes, but there is no information in randomness -- because any other minor slight random re-arrangement would have been fine. So the general presence and overall pattern of neurons is coded for in the genome, as are the rules which govern how the wiring forms -- how each individual neuron adapts to it's own local environment of other neurons.
So "fundamental structures and processes" would include the overall pattern of neurons and the rules governing how they grow & re-wire synapses. It would not include minor random variations in the exact positioning of the neurons (no information content there anyway). It does not include the detailed wiring, which, as I said, is "software" or "data" (same thing, really) along with the activity patterns, also "software" or "data".
All the above is a rough sketch. There is more to it than that. And I'm sure someone is going to pick on some detail I have not addressed and say "what about blah blah blah"... despite my newly acquired reputation for epic posts, I can't write a freakin' book here.
Posted by: eleusis
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August 21, 2010 2:41 PM
#48 Form&Function:
The problem is that there is no clear analogy between computers and brains, or computers and any biological structures and processes.
The brain is NOT a computer. The brain is "like" a computer in the same sense as a car is like a horse: at some extremely abstract level they accomplish the same thing, moving people around, or processing information, but they are so structurally different that cars tell you almost nothing about horses, and using cars to make predictions about horses is pointless. Likewise, computers tell you almost nothing about brains, and using computers to make predictions about brains is pointless.
Trying to make predictions based on bad analogies between what you know about computers and what you don't know about biological systems is a recipe for failure.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 2:42 PM
Counting the number of transistors in a CPU would give you a measure (upper bound) on the information content of the hardware only
Put down the shovel and walk away. You're apparently not computer-literate enough to be engaging in this discussion, either.
There's this stuff called micro-code - CPU instruction counts mean exactly - nothing. The brain/computer analogy is very interesting nowadays because of the malleability that has been built into silicon (silicon emulating hardware by running software) There are analogs to how brains appear to work but (as a computer guy, not a biologist) I'd treat them as thought-provoking only and not illuminating.
Posted by: Stagyar zil Doggo
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August 21, 2010 2:42 PM
Greylander and others:
In terms of the analogy between the brain and an Intel CPU, knowing the (human) genome at best gives you something like a Verilog/VHDL file for a System on Chip which includes say a CPU core, peripheral devices, as well as a variety of MEMS sensors (say accelerometers, clocks, thermometers, micro gyroscopes, and a few lasers) on the chip. You (in terms of this analogy) still know nothing of semiconductor physics, photolithography, material processing, or the basic physics of all but one or two of the MEMS devices. You've more or less figured out what resistors and capacitors are for, but are not entirely sure about transistors. Do you really think the Kolmogorov (or any other) Complexity of the Verilog/VHDL file is in any way informative of the difficulty of actually realizing the SoC in question? Or of usefully simulating it (along with the MEMS devices of course) on another computer?
Posted by: theswede
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August 21, 2010 2:42 PM
Of course as the zygote develops all sorts of environmental interactions occur.
No shit Sherlock. That's what PZ has been saying all along, and you (and others) have pretended isn't so. Glad you're finally on the train.
I think it's at least plausible to suggest that the amount of additional algorithmic entropy contributed by the environment of the womb, etc., is relatively small.
On what grounds?
Obviously it leaves out a lot of detail but even if it's off by an order of magnitude or so it is nevertheless a plausible argument.
On what grounds?
I'm simply saying that the question of whether one could actually build a simulator is separate
Of course. That is a legitimate line of inquiry, unlike talking about the Kolgorov complexity of the genome.
Or do you find it illuminating to talk about the Kolgorov complexity of argument to functions in general? You never answered that. To me, such a line of inquiry is nonsense. Please stun me with your insight.
Posted by: Dm5171
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August 21, 2010 2:44 PM
I just saw mitsu.hadeishi's post after I had submitted my own post. He says exactly what I wanted to say, and he does it better. I am not familiar with Kolmogorov complexity, so I used generic terms like "information density" to explain what I understood Kurzweil was getting at. But I defer to mitsu.hadeishi, he knows more about this aspect than I do.
The rest of his post is spot on, in my opinion.
Posted by: eleusis
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August 21, 2010 2:47 PM
And no, neural activity is not software any more than it is the electricity going through the transistors (both of which "sound" like good analogies on first pass). As long as you think like that, you will be constrained by the falsehood of your paradigm.
Posted by: ljdursi
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August 21, 2010 2:50 PM
I call bullshit on Greylander, Ed, Kurtzwell, and the rest of the accolytes.
The graph that Ed showed? I've programmed and run simulations on ASCI Red, White, and on BG/L and /P machines. Originally for astrophysical fluid simulations, now for any of a number of applications. Guess what? Having access to a computer that can perform N floating point operations per second does not even remotely give you access to all systems that nominally have that same sort of compute complexity, *much* less give you understanding of those phenomenon.
Let's take the example of some problems which *can* today be simulated at the petascale (10^15 floating point ops / second, the upper limit of todays supercomputers) We can -- and do -- perform simulations of fluid turbulence all the time. Turbulence, and turbulent combustion, is probably the single most important physical phenomenon for any of a number of incredibly important and valuable industrial processes. (Internal combustion engine, anyone?) It's not an exaggeration to say that the world economy could be improved by hundreds of billions of dollars a year with a significantly better understanding of turbulence. Turbulence has been one of the things that we've been simulating since the beginning of computing. (See what the name of two of the first three dots of Ed's supercomputing plot are called)?
We don't understand turbulence. It's been actively studied since the mid 1880s, and examined since as long as mankind has watched, fascinated, rapids in small rivers. With all our computing power, the two things we really understand about turbulence were learned by pen and paper stuff in the 1940s by one guy. (The same Kolmagorov in complexity theory, btw.)
We *can* simulate it in particular cases; but eve there, we fail, because turbulence is a stochastic process, so to see how it plays out, you really need to do many many realizations of the same simulation to see what happens. And the number of realizations you need to do to get a stochastically good sample *grows with the size of the simulation*. Increasing computer power does not automagically save you.
To put it mildly, human consciousness is more complicated than fluid motions.
And that's with todays computers. Let me tell you something about the exascale computers of 2020 -- no one has *any* idea how to program these beasts. We've been using the same techniques today as in the 1980s, and the wheels are about to fall off that bus entirely. As the computers get bigger, *even if you understand the physical model well enough to simulate it at that scale*, programming the computers gets exponentially (see what I did there?) harder as the computers get bigger. Why? Because if the computer goes from size N to 2N, the number of interactions between components goes from N to N^2.
I know that Kurtzwell really, really wants to be Max Headroom, because he thinks then he'd be immortal. (I don't understand this; a copy of him would be, but he'll still grow old and die.) But it's still not going to happen in 20 years. Sorry, dude.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 2:50 PM
Yet that fractal image, with millions of pixels -- millions of byts of data -- is generated by a simple, tiny program only a few bytes long. Which means the whole fractal image actually only has a few bytes of information content.
...yet it also depends on the vastly complex math library running in the processor - a blurred combination of software (the math library) and hardware (the math processing units in the CPU) and software (the logic of the math instructions in the CPU) and, and, and...
This discussion is eerily similar to the discussion about interstellar exploration. The optimists say "we'll just take frozen eggs and sperms and an artificial womb!" but the pessimists know that you also need bacteria to populate the intestines of the newborn, and a hugely collected and poorly understood myriad of other complicated, gooey, biological things. You wind up needing to bring damn near the whole planet along... Put differently, the programmers who wrote libc.a and gnu/cc are part of the "system" that makes the computer plot fractals.
Cretards like to throw around the 2nd law of thermodynamics as a "problem" for evolution but, of course, anyone who understands knows that Earth isn't a closed system. Your computer is not a closed system, either, at the point where you code in a few lines of fractal source code and tell it to run; there are dependencies vastly deeper and more complex than just the source code. That is the essence of Kurtzweil's mistake.
Posted by: Def-Star
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August 21, 2010 2:55 PM
Correct me if I am wrong, but a blank slate brain built up like on builds up a computer's CPU would be useless in describing a functioning brain and could not easily be programmed to perform any functions. As a brain develops, it absolutlely requires interaction with its environment within the body and outside the body, including other fully function brains for it to model itself after. Without the concurrent developmental processes tou would have a squishy lump of tissue and not much else. How do you quantify this in any way by looking at the genome at the information content of the genome?
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 2:55 PM
(also, WTF is Kurzweil going on about 'lossless compression' for? if it's lossless, it's irrelevant since it's just trading storage space for time and complexity.)
Posted by: eleusis
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August 21, 2010 2:58 PM
#70 "You wind up needing to bring damn near the whole planet along"
Yep. That's why you can fire a computer into the vacuum of space (Hubble, for example), and it works just fine, but humans need to bring the micro-environment of the earth's surface with them (air, water, food, etc). We are deeply embedded in our environment -- a fact that is proven every time you inhale. This is an important point the comp sci folks miss. We are deeply embedded and rely heavily on the environment for producing and maintaining normal human phenotypes.
Posted by: SaintStephen
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August 21, 2010 3:00 PM
How do you know this? How do you know "it won't work"? What the hell does "work" even mean in this context?You don't know, Professor Myers. Period. You've fallen prey to your own nay-saying.
So please stick to posting pictures of flowers that resemble female genitalia, and quit tearing down good-hearted technological optimists like Ray Kurzweil. Your recent attacks serve no purpose as far as I can see (except to further your own ends, whatever they might be). Dr. Kurzweil is not an enemy of New Atheism, or rational thinking, nor does he advocate religion or supernaturalism. He tirelessly advocates SCIENCE and TECHNOLOGY, and he doesn't need flower and vegetable porn to do it.
What gotten into your corn flakes, anyway. Your negativity and pessimism on this fascinating topic is most unseemly. Yes, it's going to be a "long hard slog." Thanks very much for that piece of sage wisdom.
Yawn. Where's the door. I need some California sunshine. This cold Minnesota weather is chilling me to the bones.
Posted by: Jeff Dee
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August 21, 2010 3:07 PM
Myers and Kurzweil - are we going to have to separate you two?
Posted by: nejishiki
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August 21, 2010 3:09 PM
#59
Are you taking epigenetics and alternative splicing into account here? This is a level of complexity that is not included in the raw sequence of the genome, but has far reaching effects. Kurzweil, in his response, says the there is a 'small amount of information' in epigenetic mechanisms; one wonders where the math is - or even what it would look like.
Probably wouldn't fit on the back of his envelope.
If Kurzweil's entire contribution to this controversy is a rough calculation - perhaps off by an order of magnitude or more - and a promise that technology will eventually deliver the goods, then I agree: PZ shouldn't have said what he said, because it wasn't worth commenting on in the first place.
Posted by: eleusis
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August 21, 2010 3:09 PM
#70
BTW, you bring up a good point that many transhumanists (who make the same argument about fractals) miss. If you wrote the same lines of code on a piece of paper, you wouldn't get a fractal.
Imagine if humanity was wiped out and aliens landed on this planet and found a piece of paper with those lines of code. What would it take for them to reproduce the fractal? They would have to reinvent all of the hardware and software that allow that code to turn into the fractal. That's the environment of the code, which is a lot more information than just the code --
just like the genome requires a vast molecular environment to get processed into a brain, which is a lot more information than just the genome.
Posted by: Nerd of Redhead, OM
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August 21, 2010 3:19 PM
And the lack of knowledge of science and how it works is what is chilling you. You are wrong. PZ knows of what he speaks. You don't.Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 3:20 PM
Correct me if I am wrong, but a blank slate brain built up like on builds up a computer's CPU would be useless in describing a functioning brain and could not easily be programmed to perform any functions.
Right. So imagine you've got this brain-emulator - now figure out the "software" that nature equips our brain-emulators with that allows them to learn language. To make a brain-emulator that could talk, you need to crack the problem of language learning (which is probably partly hardware and partly software) I suppose we'd need to build a virtual environment in which that brain-emulator could babble to its virtual mommy and get approving feedback just like a real child, and so on.
What Kurtzweil seems to be assuming is that downloading the brain would not just pull down the architecture, but the algorithms. Not just the substrate on which thought happens, but the process of thinking, and how thinking works. That's an interesting leap. I'm not saying that I assume thinking is anything more than an emergent property of brain + connections of neurons, but Kurtzweil's "brain is simple" argument seems to ignore that the connections are probably more important than just the neurons. The parallel distributed processing guys in the 80s (who invented neural networks) bumped up against all these issues. (Rumelhart I think it was) It's not hard to simulate parallel neuronal connections in the incredibly wimpy machines we had back then - that's just a software problem - but what the neural net guys lacked was a workable model for learning and they never got close to anything more than simplistic models of pattern-matching. It's possible that someday we'll find that consciousness is just a complicated evolution of a self-monitoring alarm loop (my favorite scenario) but that loop and how to create and bootstrap it would be a necessary part of a brain-emulator that was going to emulate anything other than a mass of blank "neurons"
Posted by: Stephen Wells
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August 21, 2010 3:23 PM
Something to consider: the fact that the genome is transcribed by polymerases to produce RNA, and some RNAs are translated by the ribosome to produce proteins, is not in "the information content of the genome" that Kurzweil is playing with.
Sure, once you _know_ about transcription and translation, and you have some polymerases and ribosomes, and a supply of tRNAs and some ATP and all that other bio goop... then you can see that some of what's being produced is more transcription and translation machinery. But there's nothing in the text string of ACGTAGCTCTTCCGATATATA... that would tell you that.
A fact for Greylander to ponder on, since he thinks the uterine environment is no biggy, information-wise: at least half of fertilised human eggs fail to implant and never get to develop. The right environment is something which after billions of years of evolution our bodies routinely get wrong. And don't even get me started on things like this: http://en.wikipedia.org/wiki/Hemolytic_disease_of_the_newborn
The fertilised egg with its brand new genome gets its start with a bunch of inherited protein machinery all buzzing away. So Kurzweil needs at the very least to consider the information content of a complete description of an entire cell and of an environment it can develop in. And of the laws of nature. And of an algorithm that can simulate all of the above.
I think we can all agree that the information content of the brain is probably bounded by the information content of the genome plus a perfectly accurate simulation of the physical universe. That's really helpful.
Posted by: nejishiki
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August 21, 2010 3:28 PM
#74
>Dr. Kurzweil is not an enemy of New Atheism, or rational thinking
Ask Kurzweil about alkaline water.
Posted by: Greylander
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August 21, 2010 3:36 PM
@ #50 Stephen Wells:
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 3:36 PM
Another thing to consider regarding "thinking" that the "downloaders" don't want to address: how do we know that people think the same way? What if our brains have 'microcode' that implements the basic stuff of thinking, but the methods by which we think are learned, i.e.: evolved? There may be some substance to this idea - read accounts of the childhoods of various geniuses and it sounds to me like Richard Feynman's thinking was not like mine; he used his brain differently than I do. And it sounds like Feynman used his brain very differently from Von Neumann and Turing probably used his brain differently from the greeter at WALMART, etc, etc. I know it's an analogy, but - CPUs have 'microcode' - the logic that turns an ADD instruction into the electrical signals that result in a piece of memory getting processed against other pieces of memory, etc. "instructions" in computers are a shorthand that triggers the execution of different pieces of microcode. Most CPUs now have some functions in microcode and others in downloadable microcode - i.e.: the hardware runs software that lies to the software to make it think it's talking to hardware. This works because the computational model has clear boundaries between "layers" like CPU/software and OS/application - but those boundaries are simply the places where we stop paying attention to details.
Possibly what appears to be "thinking" is many different ways of using brains, and it could be highly individual. It seems to me that it has to be, because people missing part of their brain can press other parts into service, for some parts but not for others. So another possibility the "downloaders" may slam into is that cognition might be individualized like memories. There might not be a "thinking loop" that can be started running on an accumulated store of memories that would turn out a person. That seems to me to be obvious. Feynman's memories, running on Ranum's "thinking loop" would not be as smart as Feynman was. Kurzweil is more than just his memories plus some standard human thinking microcode - there's also the special Kurzweil-specific subroutines that make him worship technology with the enthusiasm of a bronze-age sun-worshipper.
Posted by: F
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August 21, 2010 3:38 PM
Forget this Kurzweil noise - how about some Kurt Weill instead?
http://www.youtube.com/watch?v=_QXJ3OXWaOY
Or perhaps one might prefer another version
http://www.youtube.com/watch?v=hLIrS5dtTZI
Posted by: Stephen Wells
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August 21, 2010 3:39 PM
I still can't believe that he not only wrote "the brain prior to its interaction with the environment"; he even underlined it. Check the end of para 5.
He's got a bound on the complexity of a thing that can't exist.
He's going to die a very disappointed man. Sad.
Posted by: bobh
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August 21, 2010 3:40 PM
Reading K's rebuttal. and a couple of the comments, it seems that K confuses the brain's interaction with its environment and the developmental process.
Posted by: Silič O'Nopolitanopoulos, Färschdbischuf Beesknees aus Ulm und Klein Elguth, Elector Pharynguline.
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August 21, 2010 3:40 PM
Tom Johnson? Is that you?Posted by: llanitedave
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August 21, 2010 3:52 PM
What is responsible for the difference between the human brain and that of a chimpanzee? Is it environmental or genetic?
If you placed a fertilized chimpanzee embryo inside a human uterus would you end up with a human infant?
Of course not. It's really irrelevant to talk about all the epigenetic factors that influence brain development, because they are tightly constrained and consistent between one individual and the next. Otherwise, every newborn brain would be completely unpredictable and there'd be no definition of "human" at all.
In an indirect sense, the womb environment is also ultimately genetic, as it's the genes that specify the pregnancy hormones that will be produced, their timing, the proximity of other tissues that interact with the new brain cells, etc. Environmental factors that are totally nongenetic, such as nutrition levels, chemical or drug exposure, and potential trauma, are usually a very minor aspect of the development process. Otherwise, very few infants would be born "normal".
The point is that, as PZ states, to accurately model brain development, you need to take these other factors into consideration, but why that should turn a 20-year project into a 50-year project, or more, seems obscure. It's not like these other factors are being neglected. And for the most part, they are constants that vary little even between closely related species. It's not voodoo. Ultimately, it's still going to be the genetics that specifies the shaping of the product.
Posted by: Greylander
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August 21, 2010 3:59 PM
@#80 Stephen Wells,
[emphasis mine]
We *know* that! (or at least I do, and I am quite sure Kurzweil does as well... I cannot vouch for others on my side of the arguement) This is where you PZbots fall flat in your comprehension of information theory, following PZ right off a cliff. Holy crap.
Go read my analogy to fractal generating program above. Nowhere in the tiny little program is any information that says "color location at x=.31225,y=1.7444 with RGB value [127,32,99]", nothing in the program can directly tell you that, yet you run the program and millions of pixels get colors assigned to them. This is the creation of data, but not new information. you have to run the program on the right computer hardware. But the computer hardware contains no special information about the fractal. The information in the image equals the information in the program (unless there is special knowledge hidden in the cpu running the program, which there is not).
In the cell the situation is slightly different. The genome (program) and computer (ribosomes and other transcription machinery.. and all machinery in the cell) in this case both contain roughly the same information. Neither one can do anything without the other, but that has no bearing on the information content. If anything the genome is virtually a superset of the preserved information in the cell. By preserved information I refer to information that remains a few minutes, hours, days later... information that remains mostly unchanged in all daughter cells. There is plenty of "information" about all the particular locations, orientations, and momenta of all the molecules... virtually random, none of it preserved through to daughter cells, very little preserved from one moment to the next.
And why do you think this matters? "I didn't land in the wrong spot on the surface of the uterus, so I didn't get flushed." Does not contribute a significant amount of information to a healthy organism. Who said that the model of the brain was going to include every possible way that an organism could die or fail to develop in the first place.
And I'm starting to repeat myself and said I wasn't gonna.
"Just when I thought I was out... they pull me back in. "
sigh...
Seems to me your side is insisting the all the information in the universe must be accounted for in the fundamental structures and processes of the brain.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 4:02 PM
Stephen Wells writes:
I think we can all agree that the information content of the brain is probably bounded by the information content of the genome plus a perfectly accurate simulation of the physical universe.
That's the simulationist view. After all, if Kurzweil is right and we soon have enough computronium to completely simulate a universe from the big bang onward, eventually humans will evolve and we can watch over their shoulders as they post messages like this one to blogs. Like the fractal analogy: all you need is enough storage space plus the laws of physics, and a fast enough CPU, now that we know the universe is not infinite, it's "doable" Of course there's already a 'computer' you can run a simulation the size of the universe on - it's called "the universe"
Excuse me - I've got to go reboot my simulation; the creobot infestation on Earth #4723 is really annoying me.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawmVT1LBhwmO9ej9LNg7a5e9d-AVJ8ezfmE
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August 21, 2010 4:09 PM
Seems to me your side is insisting the all the information in the universe must be accounted for in the fundamental structures and processes of the brain.
I don't think that's what's being said. It seems, though, that a brain that is just the "fundamental structures" is useless, and you're ignoring the likelihood that the "fundamental processes" (nice handwaving!) are learned. In order to simulate-teach the learned behaviors you need to simulate a reality, right? Or else you need to be able to suck in the individualized (hence randomized) results of that learning.
The nature/nurture "debate" is a false dichotomy - it appears that a tremendous amount of what we are is a mix of both nature and nurture, to highly dependent degree. The fact that I learned English is nurture, but I probably have some genetically gifted predilictions toward language that my chimp cousins lack. When you glibly wave at "fundamental processes" you're sweeping some hugely important questions under a very flimsy piece of carpet.
Posted by: msironen
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August 21, 2010 4:12 PM
After all, if Kurzweil is right and we soon have enough computronium to completely simulate a universe from the big bang onward,
I don't know if this is being facetious or just stupid. The minimal simulator that can simulate the universe wholly IS the universe itself.
It's like claiming that predicting your own decisions is somehow different from actually making them.
Posted by: Furcas
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August 21, 2010 4:18 PM
PZ, you said that you read The Singularity Is Near. Are you sure you haven't only read the first third, or something?
Posted by: Greylander
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August 21, 2010 4:21 PM
@#65 Stagyar zil Doggo:
Greylander and others:
In terms of the analogy between the brain and an Intel CPU, knowing the (human) genome at best gives you something like a Verilog/VHDL file for a System on Chip which includes say a CPU core, peripheral devices, as well as a variety of MEMS sensors (say accelerometers, clocks, thermometers, micro gyroscopes, and a few lasers) on the chip. You (in terms of this analogy) still know nothing of semiconductor physics, photolithography, material processing, or the basic physics of all but one or two of the MEMS devices. You've more or less figured out what resistors and capacitors are for, but are not entirely sure about transistors. Do you really think the Kolmogorov (or any other) Complexity of the Verilog/VHDL file is in any way informative of the difficulty of actually realizing the SoC in question? Or of usefully simulating it (along with the MEMS devices of course) on another computer?
Yes. But let me be specific. Kurzweil side does not propose we will magically figure out all that additional stuff (in your analogy: how transistors work, laws of physics or whatever). But the Kolmogorov complexity DOES give us a very good indication of the size of an actual executable program that we will need after the necessary stuff is learn. But I have to continue your analogy.
(1) Some kind of automated fabrication facility is avaiable to us, so we actually can build the systems and do experiements on them, look at the parts with microscopes, etc.
(2) Suppose the system coded in the Verilog file is modular/hierarchical, and we are interested in simulating not every detail but some higher level modules in one section. (analogy with brain: we are not necessarily interested in simulating what ever individual [copy of a] molecule does, but we will probably be interested in how aggregate concentrations or quantities of different chemicals interact with each other (how fast does A react with B to produce C and D might be important, along with how E modulates that rate... but having saiad that, much of the metabolic pathways themselves are probably "lower level" than we are interested in and we will be looking at aggregate results of medium to large networks of reactions, along with the more obvious "wiring" of synapses and such).
(3) Now in your analogy, what the Kurzweil side is proposing is that we will reverse engineer the functioning of the high-level modules we are interested in by poking and prodding and scanning and testing and all that.
(4) The Kolmogorov complexity of your verilog does provide an upper bound on the complexity of a simulation program (executable code) unles you want to assert that the "laws of physics" in your hypothetical world (or the details of how primitive components work, like transistors) include special information about the high-level functioning of the coded system.
Posted by: Greylander
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August 21, 2010 4:23 PM
@#65 Stagyar zil Doggo:
In terms of the analogy between the brain and an Intel CPU, knowing the (human) genome at best gives you something like a Verilog/VHDL file for a System on Chip which includes say a CPU core, peripheral devices, as well as a variety of MEMS sensors (say accelerometers, clocks, thermometers, micro gyroscopes, and a few lasers) on the chip. You (in terms of this analogy) still know nothing of semiconductor physics, photolithography, material processing, or the basic physics of all but one or two of the MEMS devices. You've more or less figured out what resistors and capacitors are for, but are not entirely sure about transistors. Do you really think the Kolmogorov (or any other) Complexity of the Verilog/VHDL file is in any way informative of the difficulty of actually realizing the SoC in question? Or of usefully simulating it (along with the MEMS devices of course) on another computer?
[oops screwed up the blockquote again]
Yes. But let me be specific. Kurzweil side does not propose we will magically figure out all that additional stuff (in your analogy: how transistors work, laws of physics or whatever). But the Kolmogorov complexity DOES give us a very good indication of the size of an actual executable program that we will need after the necessary stuff is learn. But I have to continue your analogy.
(1) Some kind of automated fabrication facility is avaiable to us, so we actually can build the systems and do experiements on them, look at the parts with microscopes, etc.
(2) Suppose the system coded in the Verilog file is modular/hierarchical, and we are interested in simulating not every detail but some higher level modules in one section. (analogy with brain: we are not necessarily interested in simulating what ever individual [copy of a] molecule does, but we will probably be interested in how aggregate concentrations or quantities of different chemicals interact with each other (how fast does A react with B to produce C and D might be important, along with how E modulates that rate... but having saiad that, much of the metabolic pathways themselves are probably "lower level" than we are interested in and we will be looking at aggregate results of medium to large networks of reactions, along with the more obvious "wiring" of synapses and such).
(3) Now in your analogy, what the Kurzweil side is proposing is that we will reverse engineer the functioning of the high-level modules we are interested in by poking and prodding and scanning and testing and all that.
(4) The Kolmogorov complexity of your verilog does provide an upper bound on the complexity of a simulation program (executable code) unles you want to assert that the "laws of physics" in your hypothetical world (or the details of how primitive components work, like transistors) include special information about the high-level functioning of the coded system.
Posted by: Greylander
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August 21, 2010 4:26 PM
[just noticed another blockquote mess... repeat of #82]
@ #50 Stephen Wells:
Now, Greylander, if you can establish that the state of a just-fertilised egg depends solely on the genome contained in that egg- then you might have a point.
Otherwise, no. There is information in the system that isn't in the genome, ergo the information content of the genome doesn't limit the information in the system, and we're done.
I've been over this in detail in the first thread. I'm done repeating myself (mostly). I you weren't bothered to respond there, why would I expect you to here?
In pure information theoretic terms, it is true that random bits contain maximal information. However if the bits are truly random rand than only seeming random (as in a maximally compressed file) then there is no useful information. You can always remove randomness from your encoding of a system and put it back later during reconstruction if the randomness performs some useful purposes -- but you don't need to include a big chunk of random data in your encoding, since being random, by definition the system still does essentially the same things regardless of what random information you include, and will just be different in the details.
Randomness from the environment is certainly not part of any description of the fundamental structures and processes -- except perhaps to note places where randomness is injected into the system and how much.
Posted by: eleusis
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August 21, 2010 4:28 PM
#85
Right, a brain "before" interaction with the environment is like a computer fractal before processing by the CPU.
Posted by: redacted
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August 21, 2010 4:36 PM
What a computer scientist means by saying "the functionality of this organ is encoded in the genome" is more or less what a biologist means by saying "this organ evolved to perform a certain function". Any evolved functionality of the brain must be encoded in some location that's subject to evolutionary pressures that favor improved functionality of the brain. That's not only the human genome; human language evolves independently of the genome and ought to count too. But the number of places where this functionality can be encoded is pretty small. It can't be found in the natural environment unless there's a selection process acting on natural environments and favoring those that produce better human brains. The environment is not like Halo: Reach, it's like, well, a computer exposed to the elements. Cosmic rays will eventually produce the text of Hamlet in the computer's memory, but that doesn't happen on evolutionary time scales. It requires much, much longer than the current age of the universe.
Posted by: Kristjan Wager
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August 21, 2010 4:45 PM
What biologist would sat that"this organ evolved to perform a certain function"? Outside the intelligent design crowd, that is.
Posted by: Greylander
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August 21, 2010 4:49 PM
#69 ljdursi Author Profile
Havent' seen the graph. Can't comment on it.
Wrong. Turbulence is a chaotic process that can occur in purely deterministic processes. Unless you are simulating quantum effect, this is true of your simulations. Because it is chaotic, you must run many trials in order to make stochastic predictions about what will happen.
Any single run of your simulation is a realistic (up to computational error) simulation of a single instance of a turbulent flow process.
No one says (certainly not anything close to the 20 year mark) that we will simulate the brain to make predictions, for example, about what some bloke will be thinking/saying/doing 5 minutes from now. No one is remotely suggesting that (at the 20 year mark) we will have any way to "scan" the necessary initial conditions from a live brain (not even with a 'destructive' scan). The current discussion is not about all the "uploading" stuff.
It may surprise many in these the last two Kurzweil threads that I've never even read any Kurzweil beyond a few blog posts and maybe half an article a while back. I don't know exactly what/when he predicts about brain-uploading. I find that particular notion a bit dubious, but whether it ever becomes technically possible it will be preempted by other technological adaptations -- long before that point we will have so deeply integrated out ordinary neurons with artificial 'neurons' of some sort -- quite possible artificially engineered but mostly biologic neurons... that by the time all our original neurons completely die off, we won't even notice. I have no mystical speculations just what this means for continuity of consciousness.
so to see how it plays out, you really need to do many many realizations of the same simulation to see what happens. And the number of realizations you need to do to get a stochastically good sample *grows with the size of the simulation*. Increasing computer power does not automagically save you.
To put it mildly, human consciousness is more complicated than fluid motions.
And that's with todays computers. Let me tell you something about the exascale computers of 2020 -- no one has *any* idea how to program these beasts. We've been using the same techniques today as in the 1980s, and the wheels are about to fall off that bus entirely. As the computers get bigger, *even if you understand the physical model well enough to simulate it at that scale*, programming the computers gets exponentially (see what I did there?) harder as the computers get bigger. Why? Because if the computer goes from size N to 2N, the number of interactions between components goes from N to N^2.
I know that Kurtzwell really, really wants to be Max Headroom, because he thinks then he'd be immortal. (I don't understand this; a copy of him would be, but he'll still grow old and die.) But it's still not going to happen in 20 years. Sorry, dude.
Posted by: co
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August 21, 2010 4:51 PM
SaintStephen @ 74:
He *knows* because it's a fabulously well-documented fact! Neurons are notoriously interconnected, but spatial separation leads to diffusion times and attenuated signals. Those lead to different firing patterns, and, sometimes, only "half-fires" or no fires at all. Please, read up on neuronal interactions -- this stuff has been known empirically for *decades*, and suspected for far longer.
See (just for a tiny sampling of the literature) Phys. Rev. Letters 2004, vol 93, No. 4: "Oscillatory Activity in Electrosensory Neurons Increases with the Spatial Correlation of the Stochastic Input Stimulus" and citations therein.
Posted by: https://me.yahoo.com/a/IdqMjN5n2IB.CRlIrQvxEwkliQoG.51jOw--#077cd
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August 21, 2010 4:52 PM
PZ, I have come across your blog several times when it's been linked to various aggregators, but I'm not a faithful reader. Likewise, I barely know who Kurzweil is.
In general, I think you are spot on with a lot of your prior posts. You are thoughtful, and have a keen mind. In this case, though, you are simply wrong.
I'm with Greylander on the fact that you fundamentally misunderstand information theory. The fact of the matter is that you can, with nothing but the DNA code, create a brain. You can argue that you need the translational and transcriptional machinery to decode it, but that, too, is included in the blueprint. When you can fully define a system using a circumscribed plan, then the number of bits of information in that plan place a theoretical maximum on the number of bits in the product.
You say that the complexity of evolutionary history of the animal must be taken into account. That's not true: one impressive bit about evolution is that all of the millions of years of experience get incorporated into the DNA, and passed on.
I fail to even understand your software vs. hardware vs. operating systems analogies. If you can build the product with the blueprint, it can't be more complex than the blueprint was, regardless of what inputs and outputs it takes once you create it.
This has little to do with when, exactly, we will understand the brain, but it is a legitimate calculation on his part.
Posted by: Jadehawk, cascadeuse féministe
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August 21, 2010 4:54 PM
nope. while mutation acts on the genotype, natural selection works on the phenotype; and the phenotype is extremely dependent on the environments in which it develops. epigenetics alone completely screw with that analogy.Posted by: jmlingeman
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August 21, 2010 4:54 PM
Note: I am but a lowly CS grad student specializing in Machine Learning, so take what I say worth a grain of said.
The main problem I have with Kurzweil's assertion that the brain can be accurately modeled by a computer comes down to that even if given unlimitedly powerful hardware, we have no idea how to program a system like that. We have no idea how to program the parts of it. Strong AI has been a dead field since the mid-70s, with no signs of revival. Weak AI (single-task learning) has been growing as a field, but we're only trivially better at things like object recognition than we were a decade ago.
The field is moving quickly, but I don't see Machine Learning being able to emulate a full brain within my lifetime without several revolutionary leaps in quick succession.
Posted by: Kristjan Wager
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August 21, 2010 5:01 PM
Try reading the original post again. PZ explains why this is not the case. It's not really that hard to understand.
Posted by: j-brisby
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August 21, 2010 5:02 PM
Shame on you, Professor Myers. A man of your education should know the proper usages of 'its' and 'it's'.
Posted by: ljdursi
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August 21, 2010 5:03 PM
Yes, it is chaotic; it is also stochastic. Lots of deterministic things, even non-chaotic things, are stochastic. Otherwise no one would study random processes or whole branches of statistics except for those studying quantum mechanics, and that's simply not true.
I think Kurzweil *does* say that.
No one here denies that many of the things that Kurzweil would like to see happen may very well happen some day. But there are some very strong statements about simulating the brain being made here by people who understand neither simulation, nor the brain and its development. The simulation stuff I *can* comment on...
Posted by: Nerd of Redhead, OM
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August 21, 2010 5:04 PM
Wrong. You had better hope you missed nothing, including the turn on/off timing of all the growth factors, and their biofeedbacks, and the proper scaffolding is present for the growth in the proper directions to occur. Which is why those who claim it can be done are full of shit. Those factors aren't known, and aren't likely to be in toto for many, many years. And why folks like Greylander spew so much blather trying to cover up their ignorance.Posted by: Stephen Wells
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August 21, 2010 5:07 PM
"The fact of the matter is that you can, with nothing but the DNA code, create a brain"
Go on then. You'll be staring at the code for a long long time.
A fertilised egg, in a hospitable environment, over nine months, can create a brain from the DNA code. This relies on the code, and a lot of contingent facts about physics and chemistry, and the initial state of the egg and the womb.
The DNA is not a blueprint, it's a recipe. You can't estimate the complexity of a blueberry muffin from the compressed length of the recipe.
Posted by: Greylander
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August 21, 2010 5:09 PM
@ #97 BigMKnows:
Right, a brain "before" interaction with the environment is like a computer fractal before processing by the CPU.
Wow. This is the kind of stupid reply that makes me want to reach through the internet and slap you silly. I guess I forgot to put a warning on that post, so I'll let you off the hook -- this time.
I never made such a comparison. If you are unable to distinguish the limits of an analogy used to illustrate a specific point and how it applies to the subject at hand, you are not qualified to participate.
Posted by: Greylander
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August 21, 2010 5:11 PM
[another quote screwup... I need sleep :)]
@ #97 BigMKnows:
Right, a brain "before" interaction with the environment is like a computer fractal before processing by the CPU.
Posted by: Greylander
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August 21, 2010 5:14 PM
[wow... twice a quote screwup on same msg... now i'm being compulsive about fixing it... sigh.. sleep where art thou? ]
@ #97 BigMKnows:
Wow. This is the kind of stupid reply that makes me want to reach through the internet and slap you silly. I guess I forgot to put a warning on that post, so I'll let you off the hook -- this time.
I never made such a comparison. If you are unable to distinguish the limits of an analogy used to illustrate a specific point and how it applies to the subject at hand, you are not qualified to participate.
[ah finally]
Posted by: Nerd of Redhead, OM
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August 21, 2010 5:14 PM
Yawn, still nothing cogent, just apologetic, from Graylander. Just can't admit, like honest folks like scientists can, that they are wrong. And he's been wrong for days...
Posted by: csreid
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August 21, 2010 5:20 PM
I think Kurzweil is starting from a flawed platform. Allow me to play reverse-creationist for a moment.
Evolution does not produce simple things. The human eye is a good example: tons and tons of stuff, rigged together with layer after layer of post hoc additions to produce something that works well enough, most of the time. If we had looked at the eye when trying to design a camera - well, it wouldn't have worked so well.
Why would the brain be any different? If anything, it should just serve as a (terrible) proof-of-concept, showing that it is possible to create intelligence. I think it may be possible to simulate intelligence (maybe even relatively soon!) but certainly not the way Kurzweil is proposing.
Posted by: amphiox
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August 21, 2010 5:21 PM
Except that it isn't.
You could take your string of DNA, transcribe every single protein, every single RNA, in precisely the right proportions (these proportions, incidentally are not encoded anywhere in the genome), mix them all together, adjust for ionic concentration, temperature, pH, lipids, heavy metals, the works, and nothing would happen.
The genome can only work if it is already inside a functioning cell, and the genome does not, and never did, contain all the information needed to build the cell. There was never, ever, a moment where a naked genome appeared and then assembled a cell around itself. The genome and the cell appeared together, and co-evolved together. The three dimensional structure of the cell, the intracellular chemical environment, the topography of the cell membranes, all this information was never, ever encoded in any genome. It has always been stored in one place and one place only - the cell itself, and it has been replicated, from the beginning, by cell division.
Posted by: amphiox
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August 21, 2010 5:23 PM
The genome is not a blueprint.
The genome is not a blueprint.
The genome is NOT a blueprint.
THE. GENOME. IS. NOT. A. BLUEPRINT.
Posted by: eleusis
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August 21, 2010 5:29 PM
An interesting thing about PZ's claim that a penny doesn't magically turn into a million dollars in 20 years.
$1 million is 100 million times a penny. That's actually only 26.57 doublings (do the math, 2^26.57 = ~10^8).
So if you invested a penny and it doubled in value every 9 months, you'd have $1 million in 20 years. But you wouldn't see any significant growth for years. After 9 months you'd have 2 cents. After 18 months it would be 4 cents. Indeed, after 10 years you'd only have $327! It seems like you'd never reach $1 million, but in fact you would.
This is the so-called "magic" of exponential growth. It's a horizontal line for a long time and rapidly increases far into the future (imagine plotting the value of your one-penny investment over 20 years. The plot would only leave the x-axis toward the end).
Posted by: CJO
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August 21, 2010 5:30 PM
The fact of the matter is that you can, with nothing but the DNA code, create a brain.
Um, no. The cellular machinery to express that code the DNA gets "for free" as well as the in utero environment.
You can argue that you need the translational and transcriptional machinery to decode it, but that, too, is included in the blueprint.
You are badly conceptually confused. The DNA (which isn't like a blueprint anyway) needs the expressed result of a prior course of development to be fully formed and already working. You're asking a blueprint to be the plans and the fully operational manufacturing infrastructure at the same time. You really need to understand just how wrong that is.
If you can build the product with the blueprint, it can't be more complex than the blueprint was, regardless of what inputs and outputs it takes once you create it.
Fine, but irrelevant, for the simple reason that DNA is emphatically not a blueprint, and is not even analagous to one. To the extent that analogies illuminate this question, the genome of an organism is much more like a recipe than a schematic. And a recipe assumes ingredients and a kitchen stocked with the equipment necessary to carry out the instructions.
You say that the complexity of evolutionary history of the animal must be taken into account. That's not true: one impressive bit about evolution is that all of the millions of years of experience get incorporated into the DNA, and passed on.
All those millions of years of experience get incorporated as generalizations and passed on. "The experience" is an aggregate of the experiences of billions and trillions of individuals, in populations, in a dynamic environment that includes as salient features the activities and tendencies to act of yet more quadrillions of individuals in billions of populations over millions of years. "All the millions of years of experience" at this level of granularity certainly could not possibly be encoded in the genome to be passed along, which you should know since you're so keen on information theory. No, what the genome encodes, in a sense, is minimal "descriptions" of some of the most salient gross regularities that the lineage has encountered through time, and that is all. Confound those expectations of gross regularities by altering the environment on just a few of the myriad parameters on offer, and the genome's description fails utterly at producing viable phenotypes for the new conditions and the lineage goes extinct.
Posted by: nejishiki
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August 21, 2010 5:30 PM
#102
Absolutely false. As of now at least, and the foreseeable future, you would not know:
- the structure and biochemistry of all transcription factors in the cell, all of their targets
- the structures, identity, and targets of all miRNAs in the cell
-the concentration dependent effects of all of these
-the structure of chromatin at any given region of a chromosome
all of which will affect the functioning of the brain.
Posted by: Sintesi
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August 21, 2010 5:32 PM
I don't think information could possibly create a mind. So much of what we are is completely dependent on biochemical processes. If I speak to you smiling and joking, oozing warmth and regard or if I speak to you screaming, menacingly glaring and waving my finger in your face that is going to radically change the conversation even though the words spoken might well be entirely identical. How does information theory account for that? Such meaning strikes me more as a function of what the brain itself is made than patterns in the neuro-circuitry. Humans make decisions before they have even have a chance to think about them. Your body will tell you to be afraid, revulsed or accepting and more often than not your mind will follow those bodily decisions. That makes perfect sense in an organism that for millions of years functioned without a neo-cortex and had it slowly layered on over millions of more years. The mind is what it is and what it seems to us as possessors because of that incomprehensibly lengthy evolution. And that I suspect is inimitable due to the winding, eddying and blundering path that led to its present state. It's not like somewhere along the line we suddenly tapped into a platonic universe of intelligent thought. I want to say, "You know Ray, I don't think the mind is really 'out there'."
The other thing that gets me about Kurzweil is his reliance on exponential growth. Can he not see the possible parameters he's likely to butt up against? Properties like attention and focus, appropriate time allotment for meaningful interactions with fellow beings. You're going to need a godlike brain just to make your newly made transhumanist super brain function like a person. I'm reminded of that famous case study of the Russian gentleman who had a flawless memory which sounded great except he wound up paralyzed by the burden. Because when he remembered one thing he actually remembered everything and it all would come dumping out of him like pulling a thread on a sweater. There simply wasn't enough time to use the information in any meaningful way. In essence he had a simulacrum of the world in his head and unfortunately for him for there's only room for one world in this time scale. So what are the dimensional properties of the real world that won't accommodate the use of massive data streams? The imperfections and flaws in our present brains (e.g., lousy recall, myopic focus, etc...) might be the very properties that allow us to function. Imagine an engineer creating a computer that doesn't work properly in order for it to work properly. What's the point of having a super brain if you can't find the time or space to use it? These might well be actual barriers instead of mere hurdles. I dunno, maybe Ray can make a second computer brain so the first one will have something that can actually recognize and understand it.
Posted by: amphiox
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August 21, 2010 5:38 PM
The catalytic center of many enzymes (ie the whole functional point of the enzyme) is an inorganic ion, or group of ions, or crystal structure. Think of the iron in hemoglobin or cytochrome oxidase, or the manganese in the oxygen evolving complex of chlorophyll. Many of these mineral catalysts can do the pertinent reactions without any protein at all. The protein part of the enzyme just tweaks the parameters of the reactions.
Now where in the genetic code is the location of the Fe in hemoglobin specified? What is the base pair sequence that encodes for iron? Where in the plant's genetic code is the spatial arrangement of the four Mn ions of the oxygen evolving complex (this is the part that actually splits the water to release the electrons that the photons captured by chlorophyll energize to start off the whole photosynthesis chain, leaving the oxygen behind as waste)specified?
Posted by: amphiox
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August 21, 2010 5:43 PM
Oh, there are qualifications required to participate now?
And who decides what those qualifications are, Greylander? You?
Posted by: Greylander
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August 21, 2010 5:49 PM
@ #122 amphiox,
And who decides what those qualifications are, Greylander? You?
I never said anything about requirements. Everyone is free to participate, regardless of lack of qualifications. Ridiculing sources of stupidity is PZ's way, and it is not a right reserved solely for the PZbots, nor do PZbots get special immunity.
Posted by: ljdursi
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August 21, 2010 5:51 PM
amphiox sums it up very nicely in #115.
Let's take something the genome *does* encode - proteins. Let's take (say) one protein.
Here were, 3 years out from Kurzweil's "functional human brain simulation" as shown in Ed's graph, and we can't even simulate the folding of anything but the simplest *single* *proteins*.
First principle simulations of an entire single human cell are I have no idea how far away - but it ain't 3 years. Even though we can easily, trivially, store the human genome on a computer, we are nowhere near capable of simulating an single entire cell from first princples. There are 100 billion neurons or so in the human brain. This should put to rest the idea that because we know the genome, the brain quickly follows.
Now, you might argue that you don't ned to simulate the entire chemistry of each neuron to study, or even model, brain function. Fair enough. Lots of CS students learn to code up very quickly simple little "neural nets" inspired by neurons - in the same way lots of crappy movies are "inspired by real events" - which are capable of really interesting little tasks. That's great. But real neurons are vastly more complicated than that, and how much of that complexity you can wipe away in a reduced model and still get something which correctly models even simple mammalian brains is *not known*, and Kurzweil certainly doesn't know.
Posted by: poke
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August 21, 2010 6:02 PM
I don't think Kurzweil is insincere. I think he genuinely believes his assertions. He's just an populariser for ideas that have been floating around for decades. What's interesting, especially in the 'transhumanist community', is the incredible hostility to biology. I guess this shouldn't be surprising since hostility to biology has long been a keystone of Cognitivism ever since Chomsky proclaimed that people investigating the 'mind/brain' (as he calls it) don't need to be interested in the brain part and Cognitivism is central to the beliefs of the techno-rapture crowd.
Kurzweil likes to say that with the completion of the genome biology has become an 'information science.' We no longer need to worry about the messy lab work, since it has all been digitised, and will now be subject to Moore's Law. I see similar assertions all the time. I recall reading a posting on a transhumanist forum where somebody had asked what they should study at college if they want to be at the forefront of the fight against ageing. The replies were unanimous: What you [i]don't[/i] want to study is biology. Biology is irrelevant. Take computer science classes and, if you must, bioinformatics.
It's worth noting that the techno rapturists tend to be IT professionals and have a view of science where everything is reduced to computer science. The Universe, which is probably just a simulation anyway, can be understood as a computer and matter is really information. The brain is a computer running the software that is mind and one day we'll be able to upload ourselves into other computers. DNA is data, just like the data stored on a CD, and that's all you need to know about biology. Natural selection is an algorithm. Culture is like computer viruses. And so on.
Posted by: co
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August 21, 2010 6:02 PM
Except that if you cut it off at 10 years, and rescale, it looks the same. If you cut it off at 5 years, and rescale, it looks the same. If you cut it off at 9 months (heh) and rescale, it looks the same. *THAT*'s the magic of Exp(x). It pops right out of its definition as the solution to dy/dx = k*x.
Posted by: eleusis
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August 21, 2010 6:04 PM
#112 Greylander:
What the fuck are you talking about? Of course you didn't make such a comparison. I was talking about a quote from Kurzweil. And yet you spent three fucked up posts trying to correct me?? Seriously, dude. You're done.
Posted by: ljdursi
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August 21, 2010 6:05 PM
Continuing on with my series entitled "what ampiox said":
Water plays an absolutely, completely, essential role in protein folding. Where in the genome is described how to make water, exactly?
Posted by: eleusis
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August 21, 2010 6:06 PM
Greylander:
I was responding to Steven #85, who wrote:
"I still can't believe that he not only wrote "the brain prior to its interaction with the environment"; he even underlined it."
HE was talking about Kurzweil. Get over yourself.
Posted by: poke
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August 21, 2010 6:13 PM
I just noticed this hilarious quote from Kurzweil:
Exactly when does the 'brain' not interact with its environment? It's already interacting with its environment before it's a brain. Its entire development, the process of becoming a brain, involves interacting with its environment! Kurzweil really has absolutely no idea what he's talking about. He appears to think there's a plan for the brain in the genome that doesn't even rely on the brain being a physical thing that can and can't connect in various ways, is subject to the laws of physics, etc. These are all ways a developing organism interacts with its environment and the concomitant process of interacting with its environment through use (experience) is not separable from them. It's a continuation of the same thing. This is why it's really misleading to speak of DNA being a program, or even data, let alone a blueprint.
Posted by: eleusis
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August 21, 2010 6:17 PM
#102:
*sigh* But the laws of physics and chemistry are NOT encoded in the genome. Nothing in the genome tells you how a protein should fold, and that's turned out to be a very hard problem in biochemistry. Also, nothing in the genome tells you which proteins should interact. There may be functional groups that give you hints. Some conserved sequences can be identified as encoding functional groups that, for example, hydrolyze certain kinds of bonds, but unless you know the overall structure of the folded protein, and the details of how that structure affects its affinity for other molecules, you won't know which molecules that protein is hydrolyzing.
The important thing here is that that information has to be determined empirically. That's the hard slog.
Posted by: eleusis
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August 21, 2010 6:20 PM
and by "functional group" I meant "functional domain"
Posted by: Forbidden
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August 21, 2010 6:25 PM
To all the furists: Where's my fucking jet pack? Where's my flying car?
Pace of technology increasing my ass!
Posted by: eleusis
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August 21, 2010 6:26 PM
This point should be obvious. We already have the sequence of the genome, minus about 8% of heterochromatic material, which is the most gene-poor and irrelevant. If the genome sequence gave us the information that we needed to build a brain, we could already be building it. We are only beginning to get information on which markers predict susceptibility to some diseases (with some probability). But even that information is coming through the hard slog of empirical research.
So the question isn't how fast or cheap we can sequence over the next decades. It's how fast we can do real empirical work to link genetics to everything else we want to know, whether it's disease or the structure and function of the brain. You might claim that such work follows the law of accelerating returns, too, but if the doubling time is 20 years, we ain't gonna be there in 20 years.
Posted by: Jadehawk, cascadeuse féministe
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August 21, 2010 6:37 PM
graylander, just how many blockquote-fails is it going to take for you to realize that your browser ends the blockquote when you end a paragraph? for the sake of readability, please change all paragraph breaks in your quotes to <br>
Posted by: eleusis
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August 21, 2010 6:38 PM
#125 poke: You hit the nail on the head over and over again.
Kurzweil's critical mistake, as PZ and many of us have been trying to point out, is that nothing in biology is a purely informational science (yet). We have a the genetic sequence, and as Venter recently said, it's mostly useless. There's still a lot of empirical work left to do.
Also, the link between transhumanists and IT professionals, and IT professionals and Aspies, has been made many times. :)
Posted by: Berior
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August 21, 2010 6:45 PM
I believe Carl Sagan put it best when he said: If you wish to make an apple pie from scratch, you must first invent the universe.
To paraphrase, if you want to make a human brain, you need to understand the genetic code (we aren't there yet), understand the influence of environemental conditions upon cell developpement (we aren't there yet either), ect ect.
Or to say it simply, everything in the genome, body, and brain and godamn near everything outside of them influence everything else.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkTzptVlEZQ2er6ymj1D_wskpB_1kIRN_o
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August 21, 2010 6:50 PM
Benjamin Franklin says:
PZ can tuna fish, but Kurzweil can tune a piano.
Posted by: Tartessos
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August 21, 2010 6:52 PM
Reading this article and the last (and particularly the comments) feels like listening to a sped up techno remix of "We're Off To See The Wizard," with all the straw men being trotted out.
For reason's sake, take the time to actually find out the actual position someone is taking before attacking it.
The vast majority of critics here have not read Kurzweil's works (or don't remember them very well), because they are arguing against positions he did not take, freely making assumptions about his views, and making counterpoints he has already addressed.
Being skeptical is good, and Kurzweil has presented things that deserve healthy skepticism, but be responsible!
Posted by: Tartessos
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August 21, 2010 6:56 PM
By the way, people really should drop the "Where's my flying car?" nonsense, since we already have one.
http://www.terrafugia.com/
Find a new drum to beat on.
Posted by: Nerd of Redhead, OM
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August 21, 2010 6:56 PM
We are, you weren't. The science and his idiocy from his quotes differ. Now buzz off like a good troll.Posted by: theswede
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August 21, 2010 6:56 PM
Tartessos @139, you're arguing that RK misspoke when he said "I said that we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation within two decades"?
Really?
You're arguing his position is not what he states it is, but something else we will learn from reading more? That the plain statements made are incorrect?
If you're right, RK is such a horrible conveyor of his ideas that reading his works would be a complete waste of time.
Posted by: tylerofmanyminds
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August 21, 2010 7:00 PM
Kurzweil was originally making an argument based on the raw information of the genome, by which I mean he took the four base pairs and computed average code word length by assuming a uniform distribution on the base pairs. He was apparently assuming that all he'd have to do was store the genome in a hard-drive or transmit it over a noiseless channel, as he provided no insights as to how he would interpret the raw data.
Just to give an example of how stupid this is, consider that right now we some of the most sophisticated neural network programs and HMM's just to locate exons in DNA. Kurzweil completely neglects that interpreting the genome is straining our statistical and computational ingenuity far more than it taxes our FLOP-rate. What's worse, most of the interesting problems involved in interpreting the genome are NP-hard, meaning that we have to use error-prone heuristics rather than exact algorithms.
This is all to say, you don't even need to invoke development to understand why Kurzweil is wrong. He neglects genomics just as much as neglects development.
Posted by: chaseacross
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August 21, 2010 7:06 PM
@Forbidden
They already made a jet pack! And flying cars! They both sucked, which is why no one uses them. Make a new benchmark for "the future." I for one dream of a world where I no longer have to seperate seeds from cotton by hand.
Posted by: Greylander
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August 21, 2010 7:10 PM
@ #127 BigMKnows,
Apologies. Seriously I had just made a fractal analogy shortly before your post... and being quite sleepy (though I'm can't say that being alert would have made a difference) seems clear it was a reply to me.
Whoever gave me the tip on the blockquotes... thanks. They've been working fine til now, so I don't know if that was the problem... I'm sleepy... I think most of the time I was just fucking them up. Wasn't really worth 3x posts... so sorry bout that too.
g'nite all.
Posted by: MadScientist
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August 21, 2010 7:12 PM
@theswede#4: Well, I wouldn't attempt to stuff *that* mouse into my pockets. But as far as progress with exploiting silicon goes (and it has little to do with studying the brain), I regularly use a chip that's the size of my little finger nail and it is the equivalent of an Apple2e (from early 1980s) but with numerous peripherals built in and it can run off a watch battery rather than the bulky power supply of the Apple2e. In my lab 20+ years ago we had an instrument operated by a computer the size of a desk; 5 years ago I bought a machine that's the equivalent of about 6,000 of those computers and it's only the size of a small suitcase - and even it's a dinosaur compared to a cheap desktop machine that you can buy today.
Posted by: Greylander
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August 21, 2010 7:12 PM
"seemed" clear. important tense error in previous post.
Posted by: Michael Kingsford Gray
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August 21, 2010 7:12 PM
Ray worships at the altar of "Cargo Cult Science", as Feynman so pithily coined.
Posted by: Stagyar zil Doggo
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August 21, 2010 7:26 PM
Greylander @94,95:
What if some part of the program turns out to be np-complete? Lets say that the brain, with its O(10^23) molecules interacting through some as yet undetermined process manages to barely solve it for a data set of barely adequate size. The algorithm for simulating this process can be quite simple with low Kolmogorov Complexity. As stated by many others above, the relevance of Kolmogorov Complexity here is overrated. How do you propose to even determine the hierarchical levels of abstraction in the Verilog file? Remember, in our analogy you don't actually understand Verilog beyond recognizing a subset of the symbols used. You don't even know the physics of devices represented by some of the symbols.
Despite having little knowledge of the actual biology, I'll submit that a clean hiearchical separation is unlikely and 'higher level' subsystems will probably turn out to have been patched with 'lower level' mechanisms fairly frequently. Djikstra's memo about GOTOs or 'Good programming style' is unlikely to have percloated down to the genome yet.
The idea that you'll somehow determine which are the 'higher level' functions of the brain and limit your simulation to them, without understanding the physics/chemistry at all levels is unrealistic. Our present knowledge is limited to some elements of the lowest level - the Genome and some bio-chemistry/physics, along with some elements of the highest level - gross physiology and behavior. I fail to see us figuring out how the latter emerges as a property of the former, without developing an understanding of ALL of the intermediate levels.I included the MEMS devices in the hope that you will realize that modeling and simulating them is unavoidable in any realistic recreation/simulation of our SoC. Remember that in our analogy, we are simulating our SoC on a computer which does not have them or anything analogous to them on board. An understanding of their physics accompanied by coding the analytical solutions if known, or alternately brute numerical simulation if not, is the only alternative. This is of course assuming that the physics can be adequately simulated, contra the possibility of their being computationally difficult (np complete/hard) problems that I raised above. The same is true for simulations of the brain. Remember also that as per our analogy, we don't yet know what a gyroscope or an accelerometer is for.
PS: Please re-read ljdursi @69. Note that some of those turbulence problems that we've been unable to solve for 120+ years have trivially simple geometries (flat plate boundary layer at Reynolds number of 10^12) and can be specified in less than a page. As yet unknown analytical solutions are presumed (and have been presumed for 120+ years) to exist, on the basis of which we can postulate a small Kolmogorov Complexity. It hasn't done us much good so far.
Posted by: jafafahots
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August 21, 2010 7:41 PM
As usual, I must preface my comment by explaining that I dunno shit about shit. 8th grade education and all that.
But it does remind me of an experience from around 1998. Even then, relatively early years of Photoshop, I ran into confusion over chemical versus digital processes.
There was a client in a shop I worked briefly at that had a large format hi-res photo (way before digital cameras were useful) and they wanted the "blues bluer."
Photo was shot on film for a huge banner (billboard, essentially). No matter how hard he tried, the photographer could not get across that while he could "push the blue" by manipulating the chemical process to create a stronger blue, there was no way to avoid that having an effect on all the other colors. Chemical process. Chemicals do what chemicals do. The client wanted everything else unchanged, but just "bluer blues," and having passing knowledge of digital manipulation could not understand why one color couldn't simply be changed without a change to everything.
Dunno if this adds anything to the discussion (hell, lately I feel like I never add anything to any discussion) but it felt somehow similar to me.
DNA, cell structure, brain structure, neurons are not flash memory in other words. Chemicals.
Posted by: theswede
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August 21, 2010 7:49 PM
MadScientist @146
And do you run software on that chip which can build you a flying car? =P
My point isn't that hardware isn't progressing. Of course it is, and at an astounding rate. My point is that this progression in no way leads to automatic gains in any field *what so ever*. Including the fields of software engineering and computer science.
We had WIMP desktop systems fully working in 1968, and we're still stuck with the sucky, fragile OS paradigm which was state of the art at that time.
Hardware progresses, and software pretty much stands still by comparison. Why would it be different with brain simulation software?
Posted by: csreid
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August 21, 2010 7:51 PM
I think Kurzweil is starting from a flawed platform. Allow me to play reverse-creationist for a moment.
Evolution does not produce simple things. The human eye is a good example: tons and tons of stuff, rigged together with layer after layer of post hoc additions to produce something that works well enough, most of the time. If we had looked at the eye when trying to design a camera - well, it wouldn't have worked so well.
Why would the brain be any different? If anything, it should just serve as a (terrible) proof-of-concept, showing that it is possible to create intelligence. I think it may be possible to simulate intelligence (maybe even relatively soon!) but certainly not the way Kurzweil is proposing.
Posted by: p
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August 21, 2010 7:54 PM
I think what we're fundamentally debating here is whether it is possible, in principle, to grow a human fetus in a test tube (that is, without the inherent complexity of a mother's womb).
Kurzweil is implicitly assuming that this is possible. And, if so, the information theory argument goes like this: how much information does it take to generate a functioning infant brain? Only as much information as must be conveyed to, say, a ridiculously advanced alien lab in order for them to grow a newborn. (That's the easiest way to make "information theory" precise.) What kind of information, beyond the 50 megabytes of DNA, must be sent? Well, a description of the contents of a fertilized human egg, in (only) enough detail so that the egg is viable, and a description of an appropriate "test tube" in which to grow the fetus. No more. Simply set it up, and the laws of physics will deliver in 9 months.
PZ Myers, however, assumes that one cannot grow a baby outside the mother, because the mother must constantly "add progressively more information to the process" (his words). And this is a bold claim, and one that is patently false for, say, fish, birds, reptiles, or any other creature that we know how to incubate from an egg. Does he claim that the umbilical cord sends not just water, carbohydrates and proteins, but also, somehow, this hugely information-rich "essence of humanity", that one may as well call the soul?
Posted by: theswede
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August 21, 2010 8:02 PM
I think what we're fundamentally debating here is whether it is possible, in principle, to grow a human fetus in a test tube (that is, without the inherent complexity of a mother's womb).
And without a cell. And without regulated nutrient flows. And without temperature controls. And without proper oxygenation. And without *anything* of note except a chunk of DNA.
The fundamental debate is whether it is possible, in practice, to grow a human fetus FROM DNA, and nothing else. Kurzweil is, indeed, implicitly assuming this is possible, and PZ overtly states it isn't.
Posted by: Nerd of Redhead, OM
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August 21, 2010 8:03 PM
First of all, what soul? That religious concept with any physical evidence? That already puts your post into the realm of fiction. Evidently you haven't read recent developments in science, where is there is chemical communication between the embryo and the mother. Especially near time for birth, but also prior to that. Still not looking good for your cogency. Maybe losing you delusional deity, and learning real evidence would help you from seeming to be an illiterate idjit.Posted by: theswede
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August 21, 2010 8:11 PM
Regarding the flying car; no, no such thing has been made. What has been made is an airplane which can be driven on roads to the airport and there folded out into an airplane, but that is a very different thing. It's still just an airplane. and you can't fly it from work downtown to your garage in suburbia like you could a flying car.
A flying car is a car when flying, and not an airplane when flying. That's the whole point of them, and why having one would not suck in the least.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 8:11 PM
you gotta figure that a guy who puts his picture on every one of his blog posts is going to tend toward ego fights.
Posted by: p
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August 21, 2010 8:22 PM
Wow... for my first post, I really get pounced on by people who didn't read it. But, to respond:The end of the middle paragraph of my first post (#153) addressed all of this. But to go into a bit of detail: how many bytes of information does it take to convey a temperature suitable for incubation? I'd say 1. How many bytes of information does it take to specify a reasonable level of oxygenation? Perhaps 1, or 2. Regulated nutrient flows? Sure; specify a handful of carbohydrates, amino acids, and a rate for each to be provided to the growing fetus. How many bytes? 1000 maybe? 10000? Not much at all. So 3 of your complaints can be easily addressed with an amount of information that doesn't even raise our information quota to 51MB. Of course, compactly describing a viable cell is clearly harder than describing a temperature. But perhaps you can imagine an argument for the existence of such a description on your own?
Posted by: theswede
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August 21, 2010 8:28 PM
But, to respond
How much for the cell's environment? How much for the protein folding? What about the flow of trigger hormones from the mother? The composition of those hormones, timing, amount? You're assuming temperature is constant, which is trivially false since human temperature varies by activity and other factors. Same with nutrient flow and oxygenation. All of your handwaving is just that, handwaving; none of it is grounded in even a basic comprehension of human biology.
And no, I can't imagine a description of an egg cell which is sufficient to let us create one from raw chemicals. Please help me out.
Posted by: Nerd of Redhead, OM
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August 21, 2010 8:31 PM
No, we read your idiocy.Don't forget timing and amount. Since it needs accuratate timing, increase your fudge factor.Only in your meager brain. Not in one of a real scientist, which you obviously aren't.Irrelevant to reality, which you fail out. Loser.Posted by: msironen
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August 21, 2010 8:33 PM
This, along with a couple of recent posts, have left me very disenchanted with Pharyngula in general. It's somewhat surprising that what I value most these days is PZ's anti-religion commentary (which I tend to strongly agree with) and his reports on peer-review on biological developments (which I find interesting), but almost everything else just seems to display a willful ignorance that is best characterized by his most notorious anti-science opponents. Certainly most of the commentary seems to take a "fuck it"-attitude to a supposedly much-vaunted value of rationality.
It's very telling how any attempts to defend for example Kurzwiel's points, even by people who don't actually agree with with Kurzwiel on the big picture, are labeled as Kurzwiel's fanboys while PZ's supporters... well, best leave it at that.
Posted by: sylverfyre
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August 21, 2010 8:33 PM
Even more useless is the fact that his prediction of "we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation" is SO VAGUE that, in 20 years, he could make the claim that he was correct with his prediction assuming we make pretty much any advances in the field of neurobiology at all.
A key to making predictions that are always correct: Make them so vague and far enough in the future that you can't be wrong. Useless.
Posted by: theswede
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August 21, 2010 8:38 PM
almost everything else just seems to display a willful ignorance that is best characterized by his most notorious anti-science opponents.
Any concrete examples? This is rather a brutal accusation, so I expect you have a long list of concrete grievances.
Posted by: Nerd of Redhead, OM
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August 21, 2010 8:39 PM
They are, and they are ignorant of the amount of science required to do what their messiah claims. The science alone is a 50-200 year project, since many, many break-throughs are required to be able simulate the process on computer ask K-fuckwit described (again and again). Which the fanboi's simply can't acknowledge due to their lack of scientific knowledge, and it shows...Posted by: p
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August 21, 2010 8:42 PM
I think this comment is really at the heart of the misunderstanding here. How much information does it take to describe protein folding? And the answer, of course, is NONE. Physics does it for you. Stated another way, suppose you have communicated enough information to a hypothetical ridiculously advanced lab for them to create a viable cell, how much more information do you have to send them so that the proteins get folded right? And the answer, of course, is that protein folding is something that happens within the cell, without it sending off complicated queries to the environment "help! I don't know how to fold this protein".So, sure, protein folding is "complicated", in some handwaving intuitive sense. But it doesn't involve any intensive information exchange. It's just physics, a handful of simply-stated laws, whose effects are "complicated", but are describable by the information of a mere couple lines of equations.
Posted by: msironen
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August 21, 2010 8:50 PM
"almost everything else just seems to display a willful ignorance that is best characterized by his most notorious anti-science opponents.
Any concrete examples? This is rather a brutal accusation, so I expect you have a long list of concrete grievances."
Okay, I'll bite the bullet.
Firstly, there was the whole "computer games are and cannot not be art". This would have been a subject of genuine debate 10 years ago; 5 years ago not so much and as of today, it simply displays the ignorance of the proponent. It's not very much unlike Morris citing his creationist "research" back from the 60s.
Secondly, the anniversary of the atomic bombings. Painting his opponents as amoral nuclear 'apologists' who supposedly see nothing wrong with the destruction of 1000000 human lives, he argues that the bombings were undertaken only because of some unimaginably callous experiment of seeing how the bombs would affect a sizeable civilian target (while offering no evidence except by anecdote of Hitchens and Grayling, while contradicting well-document historical proof such as the failed military coup to prevent surrender even after the bombings).
Thirdly, this whole Kurzwiel fracas where no amount of misrepresentation of his opponent seems to be below him (such as ascribing completely simplistic notions of "emergency" to his opponents).
Posted by: p
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August 21, 2010 8:55 PM
There's a huge difference between providing an accurate simulation of exactly what would happen naturally, versus doing something simpler, yet good enough. I'll list two examples:Anyone who's ever hatched chickens from eggs can attest, you don't need to simulate the complicated patterns of a mother restlessly squirming around eggs and all the associated changes in temperature/pressure/etc. You shine a weak lamp at the egg for 30 days and that'll be about as effective as anything.
Second example: did you know that Dick Cheney has no heartbeat? The first attempts to create artificial hearts, of course, gave their users heartbeats; but eventually it was realized that it is much simpler, and equally effective, to just pump blood constantly. The heartbeat is a quirk of the mechanism of a natural heart, and has nothing to do with healthy blood flow.
In short, the information theory argument is not trying to claim that with only 50MB of information one could simulate every particular of the way you were born, but rather that around 50MB of information is enough to describe the development and birth of what almost anyone, after the fact, would agree is a normal human baby.
Posted by: theswede
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August 21, 2010 8:57 PM
And the answer, of course, is NONE. Physics does it for you.
Are we even in the same reality here? If your statement here is true, and RK has access to software which does protein folding with NO information, why doesn't he share it? And how do you know of its existence?
Or have you forgotten what we're talking about? A computer implementation of a brain starting from DNA requires a model of protein folding, and does not get physics for free. For that matter, if it's so simple, why isn't it modeled already?
I have no idea why you're talking about some alien lab. We're talking computer models here, nothing else.
Posted by: msironen
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August 21, 2010 9:00 PM
The science alone is a 50-200 year project, since many, many break-throughs are required to be able simulate the process on computer ask K-fuckwit described (again and again)."
50-200 years"? And you're accusing Kurzwiel of setting ambigous deadlines?
What's obvious here is that most of the people criticizing Kurwziel/AI research have no apprecation of the scope of the problem (as if the AI people were simply trying to build a facsimile of a biological brain) while the AI research side is actually tackling completely different problems such as decision theory (while being mostly being completely uninterested in biological problems).
Posted by: Nerd of Redhead, OM
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August 21, 2010 9:01 PM
Still the fool idjit. Won't work. Still nothing but a K-fuckwit fanboi. Learn some real science, and take the few years necessary to do so, and get back to us who have advanced degrees in the subject. Preferably, with citations to the peer reviewed literature.Posted by: Stagyar zil Doggo
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August 21, 2010 9:01 PM
Orly? Remember, you are limited to what can be done by a turing-compatible machine. You don't have no stinking physics, nor any "ridiculously advanced lab". All you can do is (essentially) arithmetic and comparison operations. Whatever the physics is, you have to code it in, which simulation algorithm constitutes added information.It is rather sad that there are so many self described technophiles who have so meager an understanding of computer simulation of physical processes.
Posted by: tylerofmanyminds
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August 21, 2010 9:01 PM
p, do me a favor and answer the following questions:
1. What is the entropy of a four character alphabet a, c, g, t subject to the distribution p(a) = 1/2, p(c) = 1/4, p(g) = 1/8, p(t) = 1/8.
2. Plain Kolmogorov complexity is bounded from above by the binary ____ plus a constant.
Some knowledgeable about information theory should be able to answer these questions or find the answer easily.
Posted by: https://me.yahoo.com/a/ON6s0JZ.2egGb2ykytkQkfyfsjk3LgRO8GQht7pSmWxUawkbt3c-#48d1d
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August 21, 2010 9:02 PM
The main problem with Kurzweil's predictions is that the timeframes he gives are too short. Fully understanding the human brain in a decade? Probably not. In a century? Not an unreasonable possibility.
Nevertheless, who is he hurting? With all due respect to Mr. Meyers, we should probably save our anger for kooks doing actual harm, like denying children vaccines or killing endangered animals for "medicine".
Posted by: theswede
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August 21, 2010 9:03 PM
msironen, I'll give you the nuclear bomb, that was just silly, but condemning the whole blog minus two categories of posts on that basis is pretty harsh. And you really have to be a bit more concrete on how demolishing precise statements is "misrepresentation" in this post and the one preceding it.
As for the gaming one, I missed it. I'll have to go look, as I would disagree with such a statement as well.
Posted by: zenstoic
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August 21, 2010 9:04 PM
The question is not whether it will happen in 20 years. As you yourself said, you don't care. The question is whether it is possible at all to model the human brain in a simulation.
Any strong materialist will have to say that yes, it is theoretically possible given sufficient understanding of the brain, its underlying mechanics, physical and chemical structure, operating procedure, encoding of information, etc. etc. Given a sufficiently powerful computer this could really be done. What would it mean if we could? Immortality in silicon? Superintelligent humanlike entities?
At the moment our understanding of the brain is very limited and this task is, without reservation, impossible. This does not mean it will remain so for all time, and to be honest even Kurtzweil is probably posting a dramatically earlier date than he seriously believes in order to be sensationalist.
The point is- it is theoretically possible. What do we do with this knowledge? Arguing over the time span is silly. We can have a debate over whether the human mind is entirely material- ie if there is a soul or other extra-material component which cannot be duplicated in a simulation. We can argue over what it means or what we should do with the ability to upload or manipulate mind-data. However simply smearing Kurtzweil helps nobody.
Posted by: msironen
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August 21, 2010 9:14 PM
Well I'm not comdemning the whole blog considering that 80%+ (you gotta give me that's a fairly generous estimate) is either about biology or pointing out some religious outrage.
But for the rest, it seems like PZ is just as fallible as the rest of us (which is not to his detriment) but his implicit claims to the mantle of rationality are, for a disturbingly numerous parts, completely bogus.
Posted by: theswede
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August 21, 2010 9:16 PM
Nevertheless, who is he hurting?
Like everyone else barking from authority and being followed, he's hurting critical thinking in others. And himself, of course. Lack of critical thinking is the gateway drug to accepting kooks doing actual harm.
With all due respect to Mr. Meyers
That wasn't particularly respectful.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 9:20 PM
and so it is revealed that PZ's subconscious actually DOES believe in a soul, and his pontificating is a result of the cognitive dissonance.
Posted by: p
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August 21, 2010 9:21 PM
We're talking about information theory, actually, which asks about what is possible, not what has already been done.
For example, the Standard Model of physics is ridiculously accurate at the everyday temperatures and pressures of biology. A computer simulation of human biology using Standard Model physics is not something conceptually beyond us, or that would require new knowledge of physics; it would simply take far too much processing time and memory to be useful. Though it would not require many lines of code.
Kurzweil is not saying that this approach will ever be feasible. He is simply saying that because it is hypothetically feasible, it automatically upper bounds the information content of a newborn's brain. If "information content" defined in this convoluted divorced-from-reality sense does not seem relevant to you, fine. But that's its definition. And to certain of us computer science types, "information content" is an enormously insightful definition. You're free to pick your own favorite insights about the world.
Posted by: Jadehawk, cascadeuse féministe
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August 21, 2010 9:26 PM
of course; because development and epigenetics = soulfucking moron
Posted by: CJO
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August 21, 2010 9:27 PM
Then why is it so hard to derive it from first principles? There's no handwaving in the assertion that protein folding is complicated, and it's quite counter-intuitive, actually, that it's as complicated as it is. Many of the same general theoretical problems bedevil the field as do the study of turbulence, mentioned above. You see, Nature is closely guarding the key to that "mere couple lines," such that, sure, it's "just physics after all" when you can see it happen in vivo --watch economical Nature iterate her "simply-stated laws!-- but we still don't know how to predict the way it will go from first principles, and that is precisely what a computer simulation given only the information in the genome and the equations governing the chemistry and physics would be required to do, and computer simulations are what we're talking about, yes?
Posted by: theswede
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August 21, 2010 9:30 PM
p, I'm a computer scientist, and information content is rather useful to me. However, this use of it does not convey anything *in context*, namely prediction of how difficult mimicking a human brain is, and therefore isn't useful. At all. It's just wankery. That a compressed genome is 50MB says precisely nothing about whether we will be able to model a brain in 20 years or not.
Posted by: grudgedk
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August 21, 2010 9:30 PM
Except that there's no evidence that this curve will continue. In fact we've already hit the wall for how small things can get, without electrons quantum jumping inside our CPU's (which is generally undesirable), and we're also reaching the limit for diminishing returns on clustering cores together. The most obvious flaw however is the 10 petaFlop of processing power needed for "Human Brain Functional Simulation" is completely arbitrary, and there is no reason at all to believe that exponential growth is real or that year is a good indication of how fast computers get. Check the top 500 super list. There are computers built this year, pushing "only" about 25 tFlops, while there are some from 2005 pushing 4 times that (see how cherry picking, can give you whatever results you want, to "prove" whatever point you're trying to make). Kurzweil even includes the MDGRAPE-3, which is a simulator, not a computer in the normal sense of the word. You're assuming that the Tabula Rasa philosophy is true. This might not be the case. You're assuming that P=NP. To the best of my knowledge, this is still up for debate. Sure it does. Kurzweil hasn't provided any evidence to support his claim, thus the reasonable assumption is that he's wrong. Large arbitrary numbers are still arbitrary. We should evaluate scientific claims on the evidence that supports them. Like others, you're assuming that P=NP. Look up John Searle's Chinese Room argument. The human mind does not function like a computer. Good science is not about gambling. Good science is about drawing conclusions based on available evidence. It doesn't matter what I believe, it matters what I can prove. Discussing when an event is going to happen is second nature to discussing whether it's even possible in the first place. Well you're wrong. You realize that there are different types of hardware right? Let's say CPU, GPU and FPGA, each have their strengths and weaknesses. One is designed to do a single complex task with a rich instruction set, another is designed for simpler tasks that can be highly parallelized, the last is a nice compromise, that generally can't execute software. If you have an algorithm and you want to implement it on any of these different hardware platforms, you're going to have to write it in a special way, or it will perform poorly, or not at all (this is why we have different programming languages like Python, GLSL and VHDL).The overall point of this is that we currently know very little about the hardware, and even less about the software. How are we going to write a simulator, even if we do get enough computing power? Do we have enough processing power to do a "Cat Brain Functional Simulation"? Probably yes. So why hasn't anyone done it yet? We've all heard that this isn't that complicated. Well cat brains are even less complicated, so get started making you own functional LOLCatSim! Prove how easy this is, build me a cat brain storage, that can actually swap the minds of two cats, without horribly killing or turning both cats quite insane.
Rubbish! Try doing the Mandelbrot set on the C-64, you'll basically have 4 colors to play with in a resolution of 160x200. Now try it on the Amiga 500. You now have 32 colors in 640x256. Now run it on your modern PC with 16 million colors in 1920x1080. The results of course are vastly different, and produce images of vastly different amount of information and even aspect ratios (the most recent hardware giving the most accurate rendition of the Mandelbrot set). Kurzweil isn't doing this to "simulate intelligence". Kurzweil is doing this for "Brain Storage", or maybe so we can build him a cybernetic brain, to replace the one he's clearly lost. The point remains that exponential growth is a mathematical concept, it has never (to my knowledge) been observed in the real world, and Kurzweil's graph illustrates this perfectly, by specifically cherry picking Supercomputers that fall on his imaginary exponential growth. What, there were no Super Computers before 1994? Seymour Cray would be so disappointed. Besides the fact that he's trying to compare Apples, Oranges, Tomatoes and Bananas, (ASCI Red, Earth Simulator, Blue Gene/L and MDGRAPE-3). I mean seriously? Intel Pentium CPUs, NEC 3200 Vector units, IBM PowerPC 440's and special custom chips, all come together to give an accurate picture of advances in computer power? Really?Posted by: David Marjanović
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August 21, 2010 9:37 PM
Man.
Predicting the 3D shape of a folded protein from its sequence is one of the great big problems in... all of biology. It requires insane amounts of computing power to get anywhere near right. I'm surprised you didn't know that there's an analogue to SETI@home that does such calculations.
The sequence simply provides an incredibly large number of possible foldings, one of which is slightly more optimal than many others. It's an NP-complete problem, AFAIK.
Nothing but electrostatic attraction and repulsion are involved. In that sense, protein folding is extremely simple, har har.
Posted by: eleusis
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August 21, 2010 9:38 PM
Kurzweil is making his prediction entirely from the computational side of the problem. Some people have estimated the computational capacity of the brain, and, following Moore's Law, we expect to achieve that capacity with computers in the 2020s. Kurzweil simply assumes that our knowledge of the brain, and our ability to translate that knowledge onto machine substrate (as code), will be sufficient at about the same time.
That's the crux of the problem. Advancements in neuroscience don't follow a tight trajectory like Moore's Law. Nobody knows when we'll have sufficient knowledge of the brain. Certainly not Kurzweil. Some even claim that computers already have the computational capacity of the brain, but the knowledge necessary to implement a brain is obviously far off.
Kurzweil's only response is that we don't understand exponential increases, but if the current rate of advancement is sufficiently low, we won't have the knowledge by 2029 even with exponential increases. Kurzweil makes no attempt to quantity the current knowledge or the knowledge that is needed, so he has supplied to basis on which we should accept his claims (a point that PZ made).
Posted by: eleusis
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August 21, 2010 9:40 PM
He has supplied NO basis on which to accept his claims.
Posted by: p
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August 21, 2010 9:44 PM
tylerofmanyminds: If DNA were completely random like you say, then yes, it would take about 700MB to store the human genome. As there are many repeated segments in DNA, one would expect better compression algorithms to compress it to less than 700MB (in fact, wikipedia claims 20MB). But whether it is 20MB, 50MB, or 700MB really does not affect the argument that much
Posted by: David Marjanović
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August 21, 2010 9:48 PM
A few days ago someone published what he calls a proof that P ≠ NP. His colleagues are currently looking for errors in it.
Posted by: Stagyar zil Doggo
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August 21, 2010 9:48 PM
A fairly trivial result from information theory has been quoted. We're discussing whether this has any relevance to the actual problem of simulating the brain. Which is as already stated, a trivial result having very little relevance to the question of how hard it will be for us to get to even a working algorithm, let alone the minimum length one suggested by Kolmogorov Complexity.You're also ignoring the possibility that even problems with low Kolmogorov Complexity can be np-complete or np-hard or even otherwise be impossibly demanding in terms of running time and memory.
Posted by: The Very Reverend Battleaxe of Knowledge
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August 21, 2010 9:49 PM
So let's assume that Kurzweil is correct—soon it will be possible to simulate a brain, my brain, on a computer. Further, it will be possible to "upload" my brain state—my memories and (heavily edited) stream of consciousness that I call myself—onto it.
So there's a copy of "me" running somewhere else. What good does that do this me, here in this body? Am I supposed to kill myself so there'll only be one copy running? I can think of a way to save myself a shit-ton of trouble in that case.
Posted by: msironen
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August 21, 2010 9:50 PM
"Like others, you're assuming that P=NP. Look up John Searle's Chinese Room argument. The human mind does not function like a computer."
Uh, P != / == NP has actually nothing to do with whether a mind (curious that you choose specify a human mind as if it were the only conceivable) is like a computer. No-one has shown a human mind to be capable of solving NP problems in P time (in fact it's very easy to stump a human on an NP problem even where a computer can solve it in a reasonable time).
If it was shown that (human) mind is a some kind of hyper-Turing P=NP machine, that would fundamentally alter the way we think about computing. You seem to be laboring under the illusion that since P=NP hasn't been proven either way, human mind is by default capable of such problem solving. Not very convincing, and not very relevant to the matter at hand, either.
Posted by: p
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August 21, 2010 9:52 PM
We're basically in agreement here: the information needed to describe protein folding is "extremely simple" (your words); but we don't really know how to take advantage of this yet.Again, the thing that provoked this whole discussion was Kurzweil saying:
Whether you find the abstractions of information theory conceptually useful/relevant is up to you. But it is what it is.
Posted by: Greylander
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August 21, 2010 10:01 PM
#149 Stagyar zil Doggo
Programs are not "np-complete", problems are. Obviously the "hardware" of the brain is fast enough to do whatever the brain does. If our estimate of the amount of computation done by the brain is in the right ballpark, how powerful a computer we need. This says nothing however about the size of executable code (as opposed to data) for the simulation.
Kolmogorov Complexity is relevant to estimating the size of such a program.
Can you even read? Did you just skim to find points to object to without taking in context? Look at point (1). We have actual brains to look at, or in your analogy we have copies of the circuit to study. We don't need to understand your verilog file.
Who said the 'separation' has to be 'clean'? Who cares? All we need to know is the set of relevant variables (things that represent or are derived from actual measurable physical quantities like local concentrations of neurotransmitters) and differential equations relating those variables.Why is this unrealistic? You just look, see "oh, it's hard" and decide it can't be done. You have no basis for this other than it looks scary complicated.
What you fail to see is no more relevant than what I don't fail to see.
Given your apparent knowledge of matter of software/hardware engineer, this last one really surprises me. We are talking about a simulation here. I do not need a combustion engine in my computer in order to run a detailed simulation of one. This is a truly nonsensical objection.
I only have to understand their physics if they are a relevant aspect of those parts or behaviors of the system I want to simulation. And if that is the case, then yes, I have to figure out their physics. So I study examples of the physical machine coded in your verilog file. Remember we have actual organisms to study, so in your analogy I get to study actual physical copies of your machine. This does not involve knowing anything about interpreting the verilog file.
Re: "NP-Complete". In the words of Inigo Montoya: "You keep using that word. I do not think it means what you think it means."
For a simulation you need equations describing the dynamics of the system and lots of number crunching... there is no "search space" of potential solutions to explore. You just crunch the numbers dude (if you have the equations).
There is no need to "solve" anything in the sense of searching a complex solution-space for optimal solutions or solutions that meet certain criteria. For simulation we just need the dynamical equations, data representing the variables, and a whole lot of number crunching.
The equations themselves are not some magical solution some optimization problem. We find the equations empirically. No one on the Kurzweil side (who knows what they are talking about) has suggested otherwise.
Read my posts on the previous Kurzweil thread. Then come talk to me.
Posted by: The Very Reverend Battleaxe of Knowledge
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August 21, 2010 10:04 PM
Wow! Somebody quoted that imbecile Searle's Chinese Room Argument? I remember reading that for the first time in Douglas Hofstadter's column in Scientific American. I had to keep checking the cover to make sure it wasn't another April Fool issue hoax. That is beyond doubt the stupidest thing I've ever seen written down in black and white—not because of how computers work, or how brains work, but because of how languages work.
Posted by: The Very Reverend Battleaxe of Knowledge
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August 21, 2010 10:07 PM
Well, there's a tag fail I never committed before. (<.i>, for future reference.)
Posted by: tylerofmanyminds
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August 21, 2010 10:11 PM
"If DNA were completely random like you say, then yes, it would take about 700MB to store the human genome."
I'm not sure where I said this. I did assume that a sequence of base pairs could be modeled as a Bernoulli random string, but it wasn't uniform, if that's what you mean by "completely random".
On the other hand, I'm pretty certain that Kurzweil did make this assumption. His calculation that it would take six billion bits to three billion base pairs would require an average code-word length of 2, which is given by the entropy function when all the probabilities are 1/4.
Posted by: Berior
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August 21, 2010 10:28 PM
All that protein folding requires is simple physics.
Than in and of itself is true, trouble is that we haven't mastered physic, not by a long long long shot. Last I checked quantum physics and general relativity are still isolated, we have no unifying theory for that, we can't pinpoint the presence of an electron, merely use probabilities of his presence.
We have mastered neither the physics nor the biology, let alone the environemental impact. There's just too many factors in play.
Posted by: Greylander
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August 21, 2010 10:29 PM
@ #184 David Marjanović:
The sequence simply provides an incredibly large number of possible foldings, one of which is slightly more optimal than many others. It's an NP-complete problem, AFAIK.
It is only an NP-complete problem when performed as a search of the space of possible folding. And even if you had infinite computing power to search the entire space and found the lowest energy folding in the space, that would not necessarily be the correct shape.
However, it actually *is* more simple than that. Real proteins don't search their space of possible shapes. The just fold. By that I mean the parts of the protein move and wiggle around according to the laws of physics. The may be high-energy barriers to the lowest energy state(s), so they do not necessarily fold to the lowest energy configuration. The easiest way to find the proteins folded shape is to simulate the physics -- start it in an unfolded shape and let it do its thing in the simulation. Right now, we can do "small" of Order(100) monomers. What we can do will scale linearly or nearly so with computational power, so Moore's law will trump this problem in time. Right now heuristic searches are faster for larger molecules, but the combinatorics virtually guarantee that the physical simulation approach will outstrip it in time.
Posted by: PZ Myers
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August 21, 2010 10:37 PM
Astonishing! So protein folding really is a trivial problem, and all we have to do is sit back and wait for processing power to catch up, and then we'll just solve it all by brute force!
You really are a fucking moron, Greylander.
Posted by: Nerd of Redhead, OM
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August 21, 2010 10:45 PM
Boy, the K-fuckwit fanboi idjits still haven't figured out that the development timing and turning on/off of regulatory developmental fuctions is absolutely critical to making anything, be it an arm or a brain. And nerves are not just connected to their nearest neighbors, but travel farther. Environment is extremely important, along with all the chemicals present, not all of which are proteins, but they are vital to the final product. And they have no idea how to do that or how it unfolds until the science tells them. No wonder idjits like Greylander come across as fucking morons. The problem requires basic science, not computing power. He just can't get that basic fact. But then, if he did, he would have to admit he is wrong, and it don't think he can do that. His ego is too big...
Posted by: Patricia, OM
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August 21, 2010 10:45 PM
You really are cute when you talk naughty PZ.
Posted by: tylerofmanyminds
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August 21, 2010 10:47 PM
"Right now heuristic searches are faster for larger molecules, but the combinatorics virtually guarantee that the physical simulation approach will outstrip it in time."
It's unclear what you mean here. Heuristics all have exponential worst cases if P != NP, but they work well in practice since they don't have to return exactly correct solutions. On the other hand, accurately simulating a physical system could require solving a number of initial value problems exponential in the size of the input. I don't think there is any complexity math to indicate that this is true.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 10:56 PM
if we take your premise that timescale is no matter, then protein folding IS a trivial matter.
methinks someone is having trouble understanding exponential growth. maybe he should read some Kurzweil.
Posted by: tylerofmanyminds
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August 21, 2010 11:01 PM
"methinks someone is having trouble understanding exponential growth. maybe he should read some Kurzweil."
No, no one should do that. He probably wouldn't ever learn that exponential growth accurately models just about nothing, because actual, physical systems can't sustain exponential growth indefinitely.
Look up sigmoid or logistic growth and get back to us, it's a much more realistic model.
Posted by: p
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August 21, 2010 11:12 PM
Ya know, I'm really rather jealous of you Greylander -- you actually got something out of this discussion. Proudly boast of it on your business cards: "called `a fucking moron' by PZ Myers."
Posted by: Malcolm
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August 21, 2010 11:13 PM
p@165
In a way you are correct: This is at the heart of the misunderstanding.
If all you need is physics, what do chaperone proteins do?
If you were right, then there would be no such thing as Mad Cow disease.
So you are correct in that the heart of the problem is people with absolutely no idea what they are talking about getting upset when they get called on their crap.
Posted by: p
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August 21, 2010 11:18 PM
Chaperone proteins do exactly what the laws of physics tell them to do, given their sequence, which is encoded in the DNA.Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 11:25 PM
> Look up sigmoid or logistic growth and get back to us, it's a much more realistic model.
ok - but i can easily envision molecular computers which continue true exponential growth for the next century.
i can easily imagine machines which will be able to fold proteins.
you can't? really?
so my point stands.
Posted by: Moenen
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August 21, 2010 11:27 PM
Kurzweil claims that reverse engineering the human brain in a decade or two and comes up with some numerolgy about the number of neurons in the brain, the number of base pairs in DNA and the number of petaflops/s that a super computer can do.
Drosophila has ~120 million basepairs, or 15 million bytes. Compress that the same way Kurzeil does into almost 1 million bytes. Assume like Kurzweil that half is required for the brain. Dividing by two so you get 500,000 bytes, or 20,000 lines of code.
Given those premises, we should have been able to reverse engineer a fruit fly brain years ago, on some crappy old computer, and these days a scientist should be able to study complex social interactions of several fully modelled fruit flies on his Iphone.
But for some reason we are still using realy fruit flies in labs, and no fly neuroscientist would claim to be able to model a fly brain any time soonish.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 11:38 PM
> Given those premises, we should have been able to reverse engineer a fruit fly brain years ago
your argument is valid, but your math is off. by a lot.
if we simply look at your basepair comparison - there's a factor of 25 difference - which by Moore's law is about 9 years. so we should be able to simulate ONE fruitfly brain, on a supercomputer, in 11 years.
do you really doubt that prediction?
Posted by: BrianX
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August 21, 2010 11:39 PM
Watching Kurzweil's defenders coming in for round two is like watching a gambler double down on a hard 20 and a full shoe.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 11:42 PM
> Watching Kurzweil's defenders coming in for round two is like watching a gambler double down on a hard 20 and a full shoe
watching PZ's defenders is like watching a sick cult - and one that's REALLY bad at math.
Posted by: BrianX
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August 21, 2010 11:47 PM
#212:
Aw, you're a stinky poopyhead too. Thanks for thinking of me xoxoxox :-)
Posted by: Nerd of Redhead, OM
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August 21, 2010 11:48 PM
Except fool, it isn't a math problem, but a science problem. Ergo, your problem is category error. And you keep repeating the same error over and over and over...Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 11:49 PM
> Aw, you're a stinky poopyhead too. Thanks for thinking of me xoxoxox :-)
thank you for belaboring my point.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 21, 2010 11:52 PM
> Except fool, it isn't a math problem, but a science problem. Ergo, your problem is category error. And you keep repeating the same error over and over and over...
hey, PZ - these are the guys defending you. surely that gives you pause...
Posted by: BrianX
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August 21, 2010 11:59 PM
#215:
Since you don't quite seem to get my meaning, lemme splain. There is never a good time to hit on a hard 20 in blackjack, so doubling down at a point in the game where you couldn't possibly have a meaningful card count makes you look either incredibly stupid or a compulsive adrenaline junkie with a death wish. There is a nonzero chance it will pay off, but at that point you're better off dumping your chips in the dealer's tip jar and going to the bar to get blitzed.
Posted by: Nerd of Redhead, OM
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August 22, 2010 12:02 AM
With you on the other side, PZ knows he is right. You are the well meaning fool of Heinlein's advice. We look for you, then the opposite of what you say is likely right.Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 22, 2010 12:03 AM
> Since you don't quite seem to get my meaning, lemme splain.
since you don't quite seem to get MY meaning, lemme splain:
your antagonistic and sidelong comments make you look like you have no point other than to say "hey guys, am i right or am i right?"
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 22, 2010 12:05 AM
> You are the well meaning fool of Heinlein's advice.
ah yes, and then the name calling. well, this has been truly enlightening guys.
oh wait, no it hasn't.
g'night.
Posted by: Moenen
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August 22, 2010 12:13 AM
@ 210
your argument is valid, but your math is off. by a lot.
if we simply look at your basepair comparison - there's a factor of 25 difference - which by Moore's law is about 9 years. so we should be able to simulate ONE fruitfly brain, on a supercomputer, in 11 years.
do you really doubt that prediction?
I really doubt that. Models depend on the information you feed into it. Garbage in = garbage out. And in 11 years, the fruit fly brain won't be understood to a degree that can be used for a computer simulation.
But suppose your assumption is true, and the first fruit fly brain will be simulated in 11 years. Do you really think the human brain will modelled only nine years later?
Posted by: BrianX
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August 22, 2010 12:14 AM
#219
Let's see: I compared you and your ilk to a somewhat dim compulsive gambler and the best response you have is tone-trolling? Why should I dignify anything you say with a serious response?
Posted by: Armored Scrum Object
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August 22, 2010 12:35 AM
IMO, Kurzweil's big failure is hidden in that deceptively simple phrase "basic principles of operation". He seems to imagine that we can necessarily boil it down and sweep the bulk of the details under the rug of a simplified model.
For people who come from an electrical/computer engineering background, this has some superficial appeal. We know that we can usefully simulate the microprocessors of a decade ago by writing programs that interpret their instructions and keep track of their programmer-visible state, or what Kurzweil would call their "basic principles of operation". We don't need to simulate the semiconductor physics or even calculate the states of idealized logic gates; we just need to have the right bits in the right registers at a given point in (simulated) time.
Where the microprocessor/brain analogy falls down hard is that the microprocessor was designed, and the brain wasn't. The main reason that we can throw away the low-level physical details in the microprocessor simulator is that the microprocessor was first specified in terms of ideal, well-defined high-level behaviors, and any quirks of the silicon implementation either evaporate into the ether between clock edges or are considered bugs. As such, it's sufficient when simulating a microprocessor -- for the purposes of running code -- to simply implement the idea; the actual device is not especially relevant for the most part. If you want to know how the actual circuit will behave, that simulation takes several orders of magnitude more computing power, and if you didn't start with a "reasonable" circuit structure, it's quite likely that the simulation will not converge at all. Even when it does converge, it may converge to an unrealistic state.
While it's probably not necessary to simulate every minute quantum interaction in order to simulate a human brain, Kurzweil has presented no compelling argument that the brain necessarily has such "basic principles of operation" waiting to be discovered. As it happens, some researchers have experimented with "evolved circuits", using genetic algorithms to produce a circuit with a specified behavior. In at least one case, they initially did not even understand how the evolved circuit could possibly work. The circuit was a mockery of the "basic principles" commonly used in circuit design. I'm no biologist, but I think the safe bet is that if the brain is analogous to any kind of circuit, it is analogous to an evolved circuit, not a designed one.
Posted by: Steven Dunlap
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August 22, 2010 1:06 AM
@ BigMKnows # 51
The dead salmon study:
reported in
Sanders, Laura. "Trawling the brain." Science News 176, no. 13 (December 2009): 16-20. OmniFile Full Text Select, WilsonWeb (accessed August 22, 2010).
What's interesting is that even these results turned out to be false:
The main point I intended in my initial post was not that functional MRIs are crap, or that a dead salmon's brain reacts to visual images, but that the use of technology and the interpretation of the results remains far more complex than Kurzweil would have us believe. Unfortunately for Kurzweil with his pop culture understanding of science and technology, it's not like Star Trek where Mr. Sulu tells the Captain, "There are abnormal readings coming from the object, sir." Readings of what? How are they modeled? What baseline exists to indicate the "readings" are abnormal? (And on and on).
The article goes on to describe other studies which show biases in functional MRI research:
The entire article is very well worth reading in full. Science news typically only summarizes other already-published articles. But some of its independent analysis makes for very interesting reading as well.
Posted by: John Morales
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August 22, 2010 2:32 AM
The Very Reverend Battleaxe of Knowledge @190,
Doesn't do anything more than genetically contributing to a child does for a biological parent; this "child" would start off thinking it was you, that's all.
So... for a prank on yourself?
What do you have to lose?
Posted by: eleusis
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August 22, 2010 2:35 AM
PZ: "You really are a fucking moron, Greylander."
And he doesn't seem to give up. I just went back and (tried to) read the 700+ comments from the first thread. Greylander has been arguing on this blog full time for four days straight. :)
Posted by: Stephen Wells
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August 22, 2010 2:57 AM
I'll add protein folding to stable solution of massively coupled systems of PDEs, on the list of things that Greylander wrongly believes to be solved problems.
Here's an example of an actual controversy in the field. The usual approach to modelling protein folding involves minimising an energy function aiming to find the folded structure at or near the ground state. But there's another and quite plausible argument that in fact the ground state of almost all proteins is to form beta-sheet fibrils, like the plaques in Alzheimer's disease, and that in fact the functional folds of proteins are long-lived metastable states.
But who cares! We'll just simulate it with powerful computers! Who cares if we know what we're even simulating!
Posted by: Stephen Wells
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August 22, 2010 3:00 AM
And another one- HeLa cells. A tiny change in regulation and a cell with a human genome will give you, not a brainy vertebrate, but an amoeba with baggage.
Those pesky facts getting in the way of uninformed speculation again. Tut tut.
Posted by: BrianX
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August 22, 2010 3:41 AM
eleusis:
It's like I said. I could probably pull out the Hoofnagel Denialist's Deck and slap together a similar spread to the average creationist, but Greylander brings something special to the party. That special thing is compulsive filibustering. I mean, the lot of them are wankers, but Greylander in particular seems to be trying to make an art of boring us into submission.
Posted by: KingUber
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August 22, 2010 4:22 AM
Dammit Ray Kurzweil, I want my robot wife, and I want her now!
Posted by: Kristjan Wager
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August 22, 2010 4:25 AM
Or maybe just overload our brains with his stupidity.
I have yet to see Greylander be right on one single, complicated issue. He is consistently wrong.
And what's more, he arrogantly assumes that he knows more about any subject that someone brings up than everybody else. In his mind, he knows more about proteins and brains than biologists. He knows more about turbulence than people who work with simulating turbulence (ljdursi). He knows more about simulations and AIs than people who has worked in those fields for decades (KG).
It's a stunning example of the Dunning-Kruger effect in action.
Posted by: Elladan
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August 22, 2010 5:16 AM
I find it rather amusing that Kurzweil thinks that Moore's Law is actually some sort of law of physics.
Most of his arguments are really based on this. If something seems computationally intractable, then hey, give it a few years. Exponential growth and all that.
And for that matter, the argument is kind of valid: if exponential growth continues, then we'll be able to perform amazing computational feats soon enough. Today's huge protein folding simulation, for example, would be like saving a jpeg is today on tomorrow's computer, and soon after that we'd run trillions at once.
The problem is: Moore's Law isn't actually a law. It's just a short term fit of where computer technology has gone in the past few decades. For that matter, it's kind of a crappy fit: computers aren't just getting faster at some steady pace. They're changing architecture to work around problems.
Your fancy new Intel processor can't really run a simple linear program much faster than a computer from five years ago -- rather, it's able to run a dozen copies of the program at once. If what you wanted was one answer, that doesn't help. And turning a linear program into a parallel program is one of the great problems in computer science. We have some solutions for it that sometimes work, but it's hardly an automatic thing.
And of course, you also have the problem that if something is NP-hard, exponential growth still doesn't make it easy.
So maybe in ten years, you'll be able to run a huge protein folding simulation on a desktop computer, but it'll still take a month to finish. Is that good? Yes! Does that mean it's a simple problem now? No.
Or maybe computers will start to stagnate. Who knows? Certainly we've been rapidly approaching a whole slew of major problems recently when it comes to making computers faster. We already gave up on clock rate -- but more cores aren't a substitute exactly. And now we're running into thermal/electrical limits as well.
The whole idea of taking some short-term success in a technology and assuming it will continue indefinitely is kind of bizarre. If you do that, of course you get some spurious results like "...and then in 50 years, magic!"
Posted by: grudgedk
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August 22, 2010 5:40 AM
I specified a human mind, because that's the topic of todays discussion, I also later specified a cat brain, because that should be somewhat easier to model, if your assumptions are true, so would be possible to achieve today. Until you have proved that N=NP, there is no way you can say with certainty that a computer is even capable of emulating a human brain, because certain functions of the brain may, as mentioned elsewhere, be NP-complete problems. No. That's what you're saying I'm saying. I said nothing like that. That's funny, because the Chinese Room Argument isn't about how languages work. It's about how comprehension works. Cleverbot will mostly pass a Turing Test, but this is not because Cleverbot comprehends the English language. Except of course for protein folding being an NP-Complete problem, and of course the fact that the Folding@home project is already pushing more than 6 PFLOPS, which is more than half-way of Kurzweils estimate for human brain simulation. That's because you live in Kurzweil fantasy land, where real world NP-complete problems, like finding the optimal layout of gates in an IC, that millions of engineers struggle with every day, are dismissed as "trivial". Your point really doesn't. Being able to imagine something is real, does not make it so. Bad at math, huh? Well I did the math and got 37500 lines of code, by using Kurzweils formula. A trivial amount of code, one could probably write in a week or two. So get to it! I never figured out the method of getting from "lines of code" to "amount of processing power needed", so I'll leave it to those who agree with Kurzweil to demonstrate that correlation. However since every program you use on a daily basis, is several orders of magnitude less complex than a fruit fly brain, going by the "lines of code" metric, running it on the iPhone shouldn't be a big deal.Posted by: https://me.yahoo.com/a/Kl1q4vMTqftWtpJ2_1aiHTsCct3ZWnpvDQ--#0f7ff
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August 22, 2010 9:21 AM
Jeff Hawkins and Numenta http://www.numenta.com/ among others already are well down the path of understanding the basic principals of the neocortex. Read his book On Intelligence. Ultimately these things will not be turing based architectures. The prototypes are already displaying (primitive)intelligence and its only 2010, this argument is over. its really only a matter of time.
I'm having trouble following any of the PZ arguments. I guess he feels there are no underlying principals? Can he prove that? My theory is that PZ likes to reinforce his self identity as this 'rigorous unforgiving debunker' like Dan Dennet (who rules). The PZ argument style too emotional and semantically vague to be convincing.
Posted by: ngong
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August 22, 2010 9:25 AM
After we solve this trivial protein folding problem, then we can solve the trivial problem of delineating the 20,000! possible protein-protein interactions (ignoring isoforms). From there, it's a small leap to work out all the other possible interactions (DNA/RNA/ligand/protein) at various temperatures, pHs, etc. Trivial.
Posted by: co
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August 22, 2010 9:57 AM
#234:
Er... wot? Why do you guess that? Has nothing that PZ has said got through?
Posted by: Moenen
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August 22, 2010 10:05 AM
@ 234
What you wrote about Jeff Hawkins sounded interesting so I looked him up.
Doesn't look too impressive though... a BS in electrical engineering and two peer reviewed neuroscience papers that got cited once. Doesn't sound like the kind of guy who is about to understand the neocortex. However, he does sound like the guy to fix your handheld computing device.
Posted by: co
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August 22, 2010 10:08 AM
I also looked up Hawkins. He's undoubtedly successful, and a bright guy. He has some good publications listed on the Numenta website. However, the code is closed-source, and people don't seem to be very enthusiastic about it (despite Wired's interesting write-up about the fundamentals).
That article (http://www.wired.com/wired/archive/15.03/hawkins.html) ends with the sensationalistic quote from Hawkins: “The core principle, the hierarchical temporal memory component, I cannot imagine being wrong.”
Now he just has to prove it.
Posted by: Nerd of Redhead, OM
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August 22, 2010 10:13 AM
Swing and a miss, while the pitcher is still in his wind-up. The problem of using the genome to determine the brain, which is what was proposed, is that the regulatory/developmental genes aren't known, aren't well defined or identified in the genome at the moment, and the amount of bio-feedback going on during development is enormous. This gene gets turned on, lays down this concentration gradient, which causes a patterning and differentiation of cells, gets regulated and turned off. Rinse and repeat time and time again. Also, once the brain is formed, experiences cause rearrangement of connections, dying of some nerves, etc. The brain is a dynamic organ. This is the information required for the calculation of the brain from the genome to happen. All the turned off regulatory/developmental genes in the finished brain would not appear in the build-up from the genome. And most of those steps I mentioned aren't known scientifically, just that they must happen.A lot of the IT/CS folks are talking about simulation of the brain, a whole different category, which isn't what Kurtzweil claimed. That can be done without using the genome at all. Which means there needs some 'splainin' on what was really said. But from the genome, no way Jose.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawkXEEO8_L7jQdb7CgEfig4ZsqzwCdYwjDw
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August 22, 2010 10:29 AM
> Bad at math, huh? Well I did the math and got 37500 lines of code, by using Kurzweils formula. A trivial amount of code, one could probably write in a week or two. So get to it!
you know, when you ignore what other people are saying, and argue against the voices in your head, you aren't very convincing.
well, except to the other fanbois.
Posted by: eleusis
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August 22, 2010 10:44 AM
Brian: heh, actually you posted a lot more times than he did. I just copied the 769 comments from the old thread into a text file and sorted them by unique posters and number of posts.
The top commenters were:
61 Posted by: BrianX
53 Posted by: KG
48 Posted by: John
44 Posted by: Greylander
Interestingly, there were exactly 200 unique commenters on that thread. Quite a response thanks to Gizmodo et al.
Posted by: pccdrski.myopenid.com
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August 22, 2010 11:11 AM
Recently got AI from Netflix and only got a third of the way through it. The brain is a recipe , NOT a blueprint.
To all of these futurists, the Promised Land is always just over the next hill. And that hill is surprisingly close!
Think of a social interaction an outgoing four year old can maintain. Thanksgiving at Aunt Mary's house. Meeting new relatives. Matching up cousins with siblings. Uncle with Aunt. Uncle Joe is mean. and took your seat. Granma is saying things that don't match the conversation and she is not to be trusted. Etc. Etc. I'm not a clinical psychologist, but I'm sure an analysis of that specific situation would reveal hundreds of evaluations and decisions made by that four year old. AI ain't human!
Posted by: theswede
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August 22, 2010 11:12 AM
eleusis, try doing a word count instead of a post count. Many small comments is the norm on a medium like this; the walls of text Greylander barfed out isn't.
Posted by: eleusis
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August 22, 2010 11:35 AM
lol. That would be considerably harder on unformatted text, but I get your point. :)
Posted by: BrianX
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August 22, 2010 12:34 PM
Besides, eleusis, I have at least 45% less ignorant bloviating, with or without the toxic levels of snark.
Posted by: Stephen Wells
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August 22, 2010 12:59 PM
I've had an epiphany.
The genome does not code for the cell.
Bear with me. The genome codes for the components of the cell. If the transcription and translation of the genome is taking place within a cell, then those components go to maintain the cell. But if you take the human genome and the translation equipment and all the tRNAs and ATP you want and set them going outside a cellular context, will you get a human cell self-assembling from components?
You will not.
The genome doesn't code for the cell because in four billion years and more, it's never had to. Every successful replication of the genome of every ancestor of each one of us took place inside a cell, and that chain goes all the way back to some facts about the physics of phospholipid vesicles in salty water, a long long time ago.
I feel pretty deep right now. :)
So Kurzweil and Greylander and Uncle Tom Cobbley and all can spend as long as they like staring at their however many bytes of genetic sequence information, but there are facts about biology that they will never find in there.
Posted by: Sven DiMilo
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August 22, 2010 1:08 PM
Stephen Wells: that is an important, and, OK, deep point.
Cell Theory still makes the genome necessary but insufficient for brain development.
This ties in, I think, with arguments I tried to make on one of the Ventner threads.
Posted by: Stephen Wells
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August 22, 2010 1:19 PM
@Sven: I am now forced to hate you for having had my great idea before me :)
Posted by: eleusis
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August 22, 2010 1:41 PM
Lipid bilayers may form spontaneously, but over 400 genes regulate some aspect of the cell membrane, including the addition and maintenance of proteins, sugars and modified lipids to produce receptors, channels, lipid rafts, vesicles, etc. The genome has a lot to say about the cell membrane.
Posted by: amphiox
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August 22, 2010 1:42 PM
Chaperone proteins do exactly what the laws of physics tell them to do, given their sequence, which is encoded in the DNA, and the local environment (such as temperature, pH, ionic concentration, and the concentrations of all the other proteins) which is NOT encoded in the DNA.
Posted by: amphiox
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August 22, 2010 1:46 PM
Of course it does. But not everything. Which is the point. The very first cell membranes formed without any input from any genome, and every single cell membrane that ever existed after that descend from the direct replication of another cell membrane. No genome has ever produced a cell membrane entirely from scratch.
Posted by: amphiox
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August 22, 2010 1:49 PM
Stephen Wells #246;
Exactly. The genome doesn't even contain enough information to code for a single cell, let alone a brain.
See my post at #115. But you expressed it more clearly, I think.
Posted by: mvanbebber
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August 22, 2010 2:25 PM
@PZ Meyers:
I'm afraid I have to add to the list of failed analogies and misunderstandings on the part of PZ Myers. Actually, if you put a penny in the bank and doubled it every year, you would have $10,485. If you waited just 6 more years, you WOULD have a million dollars! Surprising? That's because you still don't understand the power of exponential growth. Perhaps you were referring to amortization?
Like I said before, 10 years vs. 20-25 years most certainly does matter, because it is the difference between a multiplication of current tools by 10,000 or 1,000,000. To claim this doesn't matter is a bit like a pony express rider claiming that email "won't make a dent" in his business. Utter misunderstanding, PZ.
Posted by: Kristjan Wager
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August 22, 2010 2:42 PM
So, in other words, he wouldn't have a million dollars in his retirement fund after 20 years. It would actually be pretty far from a million.
Yes, six more years would give him a million, if the growth was exponential, but that doesn't change the fact that he wouldn't have the money after twenty years.
So the analogy stands, and your reading comprehension fails.
Posted by: Kristjan Wager
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August 22, 2010 2:45 PM
And of course, there is no real evidence of neither a exponential growth nor any evidence for an exponential growth in the future.
Posted by: julset10
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August 22, 2010 2:46 PM
as Kurzweil's Law of Accelerating Turns predicted this entire argument and the whole premise of reverse engineering the brain has been made obsolete by two newer paradigms that require NO knowledge of the brain to capture it's secrets and augment it-
the path to AI will not be high-level software engineering or robotics- not because these aren't feasible but because they will take much longer than other routes that will make this approach obsolete-
the most likely and promising approach is IA- Intelligence Augmentation through BCI- BCI gives you understanding of the brain- not the other way around- BCI only needs the resolution to see and stimulate neurons- with BCI you can copy the brain without understanding it by simply recording the network connections and function over time - you interact with each person's unique sensory cortices by active trace probing
and the next most likely is Wolfram's NKS searches for intelligent code in the Computational Universe- this approach would yield incomprehensible black-box like kernels of code that unpack into even more incomprehensible and more complex programs that behave intelligently and with true consciousness yet will be more hard to figure out than the brain because they will be based on their own unique evolutionary history that will have nothing to do with ours- even the ideas of embodiment and senses may be irrelevant because 'found' AI will be so alien that these ideas of moving through and being aware of the environment may not even apply- they could come from regions of the computational universe that have no analogues of space or matter
Posted by: PZ Myers
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August 22, 2010 2:48 PM
You have a bank that doubles your investment every year? Please do name this miraculous place. I would like to put $100 in it.
You are using exponential as a magic word, as I said. I'm fully aware of the power of exponential increases. However, when you say something like 'because of the exponential increase in knowledge, we will understand the brain in 10 years', you are making multiple errors.
1. What are you measuring? Number of bits of data, number of brains analyzing it? Because you can't take a number to an exponent unless you have a well-defined number.
2. What is that exponent and what is the span of time? People are pretty blithe about claiming a doubling every year...but I can tell you, there is no way our knowledge about the brain is doubling every year. Papers are piling up, data is accumulating, but even that doesn't translate into knowledge.
You guys, including Kurzweil, just keep waving your hands about mathematical rates of increase, but you've got no metrics, no data, and no way to actually measure whatever the hell you're all talking about.
Posted by: julset10
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August 22, 2010 2:48 PM
that was supposed to be Law of Accelrating Returns-
Posted by: PZ Myers
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August 22, 2010 2:53 PM
Man, you Kurzweilians really are anti-scientific kooks.No. That will not work. That will not constitute new knowledge, as far as I'm concerned. It's just a rarefied form of theology.
If you're doing science, you aren't sitting in an isolation chamber running simulations -- you are out there measuring the real world. The only kind of knowledge you can get from your plan is knowledge about how computers work, which is useful, but says nothing about how the brain works.
Posted by: julset10
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August 22, 2010 2:56 PM
>>You guys, including Kurzweil, just keep waving your hands about mathematical rates of increase, but you've got no metrics, no data, and no way to actually measure whatever the hell you're all talking about.
LOL!
http://www.singularity.com/images/charts/thumb_BrainScanningTime.jpg
a molecular recording of a brain IS by definition an AI and is an 'uploaded' version of the original brain- therefore as soon as molecular level resolution of the brain is possible the argument is over- WITHOUT any understanding at all- you don't have to understand to copy and reprogram- you only have to SEE all the elements of the system and record them
the very idea of trying to re-invent the wheel is not very clever- I can have sex with my wife and have her produce an intelligent being- i just need to copy that- not understand it
Posted by: julset10
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August 22, 2010 3:02 PM
>>If you're doing science, you aren't sitting in an isolation chamber running simulations -- you are out there measuring the real world. The only kind of knowledge you can get from your plan is knowledge about how computers work, which is useful, but says nothing about how the brain works.
this is a direct claim against the Church-Turing Thesis! who is talking about theology? you are advocating that the "world" is some magical thing that is set apart from the Computational Universe-
it is not-
Posted by: Nerd of Redhead, OM
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August 22, 2010 3:12 PM
Corrected your mistake. Don't make it again.Posted by: PZ Myers
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August 22, 2010 3:14 PM
You're kidding, right? That brain scanning time image is a perfect example of the kind of meaningless bullshit Kurzweil builds his case upon.
That is, apparently (it's very poorly described), a graph of the time needed to do a brain MRI scan, which produces an indirect measure of metabolic activity within the volume of the brain. It is a snapshot of one measure of activity. It does not tell you how it got there; it cannot be used to predict what activity will look like a millisecond later.
It is not a molecular recording. It isn't even trying to record the distribution of molecules or their state in the brain.
You can upload it to a computer. You will not have a version of the original brain. You will have a picture that Kurzweil fans can masturbate to while imagining they've captured the whole of how a brain works.
Even if you had a perfect 'molecular' recording (I don't even know what that is, and you don't either), you won't understand the brain and you won't be emulating the brain unless you also understand how the substrate will shape the pattern of brain activity.
Posted by: eleusis
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August 22, 2010 3:21 PM
Here's another figure from Kurzweil. Someone completed the part that he conveniently omitted. Turns out the Singularity already happened:
http://www.kk.org/thetechnium/Blog_Kurzweil.gif
Posted by: Tartessos
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August 22, 2010 3:25 PM
Nerd of Redhead, OM:
msironen@#161 got your number, so wipe the foam off your mouth.
theswede@#142, I agree that 20 years is the actual number asserted (as I recall, 2029). That doesn't change the truth of what I said, though. It would be a full time job correcting straw men here.
Posted by: julset10
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August 22, 2010 3:26 PM
just some naive dualism- nothing to see here folks
the scan image gives you a handle on a real prediction when molecular resolution can be achieved- when it is you don't need to understand the brain to record it- if you can record it you can edit the recording and then begin PROPER EMPIRICAL science of watching the brain work and reproducing the results with pattern recognition - your primitive and flawed idea of science is merely the old 19th century scientism filled with wrong assumptions about everything- naive materialism- you assume that matter itself has some primacy or special vital aspect that is missing from the causal patterns of it's organization and rules of motion- completely without a reason other than the hidden Monotheism that lurks at the foundation of all such classical/materialistic/dualistic thinking-
is it any wonder why it is only no-nothing low-level engineers from podunk junior colleges in Indiana [or Montana] that are always criticizing Kurzweil and the idea of a Singularity- while the LEADERS of theses fields like Seth Lloyd the head of engineering at MIT or Lord Martin Rees the Astronomer Royal of GB or Steven Wolfram the creator of Mathematica or Marvin Minsky the father of AI himself who has been called "the smartest man in the 20th century" find some version of the Singularity idea to be self-evident? geniuses who got their first PhDs as teenagers and who created new paradigms of science and technology against the rabble of uninformed and ignorant meme-parroting fools who barely got their Bachelor's degrees
Posted by: Sven DiMilo
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August 22, 2010 3:30 PM
so...wait...monotheism underlies materialism and dualism? That confuses my brain.
by which you mean, uh, biologists?
Posted by: eleusis
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August 22, 2010 3:33 PM
LOL, julset10 basically just called PZ a monotheist. This shows how devoid of reality he is.
Also, argument from authority and nyah-their-smarter-than-you. I thought you all were committed to rationality?
Posted by: Nerd of Redhead, OM
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August 22, 2010 3:34 PM
All presented by the IT/CS folks, who keep getting the science WRONG. So they talk one thing, we talk another. And never Mark Twain shall we meet. Nobody from the IT/CS end has shown the science is even close to what is needed to be able to simulate the brain from the genome, which is the claim on the table. Not that computers may eventually, through AI, simulate the brain. Two totally different categories. PZ and I arguing the biochemistry, not the computer end. You can take your computers elsewhere. Talk the biochemistry, which is PZ's claim.Posted by: PZ Myers
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August 22, 2010 3:37 PM
Ah, the downside of the power of exponential growth -- it also means that when you miss your deadlines, you miss them by a lot.I just noticed something odd about the graph Julset10 just linked to — it doesn't add up, and doesn't match the sources. It claims that the 'brain scan image reconstruction time' in 2004 was 0.0025 seconds...which is insane. We can't do whole brain voxel scans at the rate of 400 per second (temporal resolution of 2.5 msec) in 2010! And when you follow the link to a source about MRIs, they cite a machine that can scan a single slice, with a resolution of 0.02mm, in 0.01 seconds.
It makes no sense. He's making up numbers about how long it takes to scan a brain (or more likely, he's fudging metrics: 0.0025sec might be the time to render a voxel array, which is something entirely different).
And julset10, of course, just credulously regurgitates it as if it is something meaningful.
Posted by: Nerd of Redhead, OM
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August 22, 2010 3:46 PM
Ah, yes, and if you can't do a brain scan to the nm level, it is worthless for figuring out the state of the nerves. After all, the molecules are finally seen at the nm level. Then you can tell what receptors are present, and what that nerve releases. Definitely need real exponential growth in MRI technology for the ability to do realtime MRI at the nm level.
Posted by: First Approximation, L'esprit de l'escalier
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August 22, 2010 3:47 PM
Wrong:
Posted by: julset10
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August 22, 2010 3:56 PM
>>And julset10, of course, just credulously regurgitates it as if it is something meaningful.
I already told you that this simply showed an indication of when molecular resolution would be available- now you are just foaming at the mouth - your whole issue with the image makes no sense- and reveals your intellectual dishonesty-
seriously are you suggesting that there will be some magic demon to prevent us from scanning anything to that resolution?
if not then you are merely arguing that a recording with ALL the elements that matter to the system- blood/water/neurochemistry- the environment- will not be understandable and no patterns will be found- even though this is directly disputed by all neuroscience up to the present- where we have found patterns and rules that can be compressed-
I am an advocate of actual rational thinking and the method of science- not of scientism and ideological assumptions that a represented as rational
/:set\AI
Posted by: Greylander
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August 22, 2010 4:00 PM
@ #199 PZ Myers:
This coming from the guy who thinks "ontology" is a good metaphor for a computer program. You completely lost credibility on matters computational with that one, PZ.
Many highly non-trivial problems nonetheless crumble under the weight of number crunching power, PZ. The worst-case algorithms for physical simulation of protein dynamics in all its detail are O(N^2)1 (super hard-core simulations that tracked all the individual molecules of the solvent as well as the protein itself could conceivably be O(N^3) if simulated volume scales with length of protein sequence, but given we have good models that already that don't need to do that simplify the effects of the surrounding solvent and do just fine, such detail is unlikely needed for most practical purposes). So each factor of a 100 in computing power will get us *at least* a factor of 10 in the size, or in the number of simulations possible in a given time, or any combination of the two. O(N^2) simulations are only necessary if you model the forces between every pair of particles (atoms in the most detailed simulations) and since the forces drop off rapidly with distance, there are many ways to simplify the simulation to O(N log(N)) or even O(N) at the cost of some accuracy but huge speed up.
In any case, even at O(N^2) (or any polynomial complexity) we still get exponential rate of improvement (do I have to do the math or can you work it out for yourself?) as long as raw computing power increases exponentially -- and there is no foreseeable reason why a generalized Moore's Law is going to peter out any time soon.
We can already do all-atom physical simulations of "small" proteins. There is nothing that prevents scaling up to larger proteins except the need for computing power. There is nothing that prevents simulating for trials or longer simulated-times except the need for computing power.
There are also plenty of techniques and shortcuts already in use today, which will still be useful -- even more useful with more raw computing power. For example, if we have solve the shape for one protein, then simulation of proteins with similar sequences or long identical or nearly-identical sections can benefit by using the known protein shape to suggest a starting point.
A great deal of research in computational protein folding has to do with finding heuristics and shortcuts to speed up the searches or simulations while sacrificing as little accuracy as possible. All these techniques will scale, and research on these techniques will continue even as more computing power comes on line. Sufficient computing power would actually render many of the shortcut simplification unnecessary (in simulations, not so much true in the combinatoric search algorithms), but that is further in the future.
Also, the gathering of empirical data is going to continue. With better and faster, more automatic lab techniques. That empirical data will also be used to inform and simplify the computational simulations. No one suggests that we all just sit on our hands (except for chip manufacturers) and wait and then magically the computers will start telling us all the protein shapes.
1 For the uninitiated, O(n) notation means that the time it takes to run an algorthm (program) is proportional to n, all else being equal (such as speed of cpu), where n is a measure of the "size of the input". In this case "N" would be the number of particles simulated. It would be the number of atoms in the case of an "all-atom" simulation of the protein. In more simplified simulations it might be the length of the protein sequence. O(N^2) then means if you double the number of particles, you quadruple the time it takes to run an otherwise similar simulation. Exponential growth of computing speed far outstrips N^2.
Posted by: eleusis
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August 22, 2010 4:04 PM
By the way, here is a blown up version of the Countdown to Singularity graph. Look at the stuff that he uses for data points.
He's comparing disparate things like the arrival of eukaryotic cells, the arrival of Homo sapiens, spoken language, agriculture, printing, and the computer. These are supposed to be data points that are informative about the arrival of smarter-than-human intelligence.
It's bullshit through and through.
Posted by: Kristjan Wager
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August 22, 2010 4:07 PM
elusis, PZ wrote a piece about that silly graph some years ago (you can find a repost here)
Posted by: PZ Myers
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August 22, 2010 4:07 PM
Ontology ≠ ontogeny.<rolls eyes at another greylander screed>
Posted by: Greylander
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August 22, 2010 4:16 PM
eleusis:
The top commenters were:
61 Posted by: BrianX
53 Posted by: KG
48 Posted by: John
44 Posted by: Greylander
Interestingly, there were exactly 200 unique commenters on that thread. Quite a response thanks to Gizmodo et al.
@ #243 theswede:
So fucking what?
Oh I get it. PZ writes a long blog post (this time it happens to be full of stupidity). Then the rest of us just get to say "Go PZ you're so right!" "No he's not" "You're stupid!" "No! You're stupid!"
I decided to take a shot at giving serious and thorough answers. Just to see what would happen. Ya know what happens? People just make hand-wavy generalized counter "arguments". Apparently no one (well very few) has the guns here to engage in serious point/counterpoint.
Posted by: Kristjan Wager
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August 22, 2010 4:16 PM
This of course leaves out the fact that n is a short form of writing cn+k, where c is a multiplying factor and k is an constant. c and k can be non-trivial numbers of course.
Greylander also ignores the possibility of O(1^n) or even O(n^n), which occasionally happens. In the later case, e.g. when someone has to traverse all edges in a graph where all nodes are connected (or nearly so).
So, in other words, the focus on some sort of upper bound of O(n) or even 0(n^2) is of course just a random upper bound picked by Greylander.
Posted by: Nerd of Redhead, OM
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August 22, 2010 4:22 PM
No, only in your deluded mind. It will be there when it is there. And I don't think it will be there for quite a while. No driving force, unlike early need for something to complement CAT scans. Not when you wish it to be there. You need to stop frothing at the mouth. Talk the biochemistry, or go away.The only stupidity occurring around her is your posts graylander. They are content free. They don't talk the biochemistry, which is the topic, they talk computers, which aren't. Get with the program.Posted by: Kristjan Wager
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August 22, 2010 4:25 PM
Greylander, you continue to make wild and unsupported claims, false analogies, and blatantly ignorant remarks - even to the point where you correct other people with nonsense. People have continuously through all this engaged with you, and tried to correct your misconceptions, yet not once have you conceded that you are wrong on even one point.
So, why should we continue engaging with you? Why should we bother reading through your long screeds of ignorant rambling?
Posted by: Kristjan Wager
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August 22, 2010 4:35 PM
Yes. This.
It's be quite annoying that some people haven't been able to figure out that it's not the computer part of the equation we are talking about (though that is pretty bad), but rather the knowledge that we need to base the simulations on. It doesn't matter if Kurzweil is right about the exponential growth in computer power (he is not, and he also ignores the software side), it would still not be possible to create simulations without understanding what should be simulated. And our knowledge is nowhere close enough for that yet.
It's not really that hard to understand, but apparently some people think that if we just throw enough computer power at some problem, it will be solved. It won't. Computer power will help, but it won't do it alone.
Posted by: Tulse
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August 22, 2010 5:05 PM
The Marvin Minsky who said in 1967 that "Within 10 years computers won’t even keep us as pets"? You mean that Marvin Minsky?
AI researchers are like fusion researchers -- they have been promising astounding breakthroughs in the "next decade" for half a century or more.
Posted by: BrianX
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August 22, 2010 5:12 PM
I decided to take a shot at giving serious and thorough answers. Just to see what would happen.
YM "bloviating pretentious filibusters". HTH. HAND.
Posted by: KG
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August 22, 2010 5:16 PM
*snort*
Googlemess@234 thinks a commercial webpage promoting vapourware shows that "this argument is over".
A basic point for Greylander: no, neither the brain's fine structure, nor neural activity, is anything like software. The brain, being an evolved rather than a designed system, isn't separated into hardware and software. GOFAI was based on the premise that you could produce a true AI by isolating "basic principles" of cognition. The neural networks approach was based on the premise that you could do it by isolating "basic principles" of learning by altering connection strengths. The idea that you'll do it by isolating "basic principles" of the "design of the brain" is another variation on the same fundamentally flawed idea. None of these approaches is useless, and there is nothing impossible in principle about producing a true AI, and nothing magic about the brain, before you revert to those idiotic misrepresentations of anyone who disagrees with you. But evolution by natural selection does not rely on exploiting a limited set of "basic principles". It uses whatever works a bit better than the current multi-level tangle, given the ill-defined, ever-shifting range and distribution of extremely complex environments in which the genome finds itself. To see what I mean, read this paper by Adrian Thompson. It was indirectly referred to above.
Posted by: Stephen Wells
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August 22, 2010 5:25 PM
Greylander, as a researcher in the field, let me tell you that when you say "We can already do all-atom physical simulations of "small" proteins", you mean "We can do simulations of a few nanoseconds of dynamics of a small protein in an unphysical situation using empirical force fields with a huge number of rather dodgy parameters and known-wrong functional forms and without taking into account any quantum effects such as any chemistry. Or we can try to do chemistry using quantum mechanics in which case we use DFT which is based on a functional which we don't know the actual form of so we use guesses which are known wrong."
Posted by: Elladan
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August 22, 2010 5:27 PM
Greylander:
Really Greylander? What makes you think Moore's Law is a law? It's not, you know. It's a crappy fit of the progress in compute power over time in the past. You have no particular reason to think it will continue. And for that matter, it's at best a poor fit.
Your argument is akin to two rabbits sitting down together on a clear night and looking up, saying:
"I say dear, if we were to have a dozen baby bunnies, and then each of them have a dozen each, why, in a mere thousand years bunny kind will take up the entire volume of the universe, and it'll just be bunny after bunny as far as the night sky goes!"
"My word! We shall rule the universe!"
... all the while failing to realize that they were sitting on the last bit of good grass in 50 miles, and they were at the brink of starvation.
Sure... with exponential bunnies, that would even be true. Except reality doesn't work like that.
We don't know how powerful computers will be in ten years. We can try to guess -- but any such guess has to be based on semiconductor physics, research, and manufacturing techniques. Not on Moore's Law.
Posted by: KG
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August 22, 2010 5:44 PM
On the last thread, there were several references to the "Blue Brain" project headed by Henry Markram. Here's Markram from an interview in SEED Magazine:
Now compare with an extract from the Blue Brain FAQ:
Markram is clearly a fine neuroscientist - and an absolutely outstanding self-publicising bullshitter.
Posted by: Greylander
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August 22, 2010 5:45 PM
@ #227 Stephen Wells:
Here's an example of an actual controversy in the field. The usual approach to modelling protein folding involves minimising an energy function aiming to find the folded structure at or near the ground state. But there's another and quite plausible argument that in fact the ground state of almost all proteins is to form beta-sheet fibrils, like the plaques in Alzheimer's disease, and that in fact the functional folds of proteins are long-lived metastable states.
Any physicist worth a damn could tell you that a system such as a protein will have a complex energy landscape with many local minima. A protein may get caught in a deep local minima with steep barriers. It may oscillate between two or more minima separated by low barriers. It may never even be able to reach the ground state, if the ground state is surrounded by barriers that are too high.
The problem you mention is the sort of question that comes up due to insufficient empirical data. Right now we lack imaging systems fast enough/high resolution enough to watch protein dynamics in detail. Nor (obviously) can we presently do detailed simulations of any but "small" proteins. Computing power is the only major limit to to the size/quantity of simulations we can pragmatically do. When we are able to do the larger simulations, questions like the one you pose can be answered simply by watching what the simulated protein actually does. If we ever have sufficiently powerful imaging, we'll be able to even just watch the proteins to see what will happen. Predicting improvements in imaging is much less certain that increases in computing speed. But we can be confident that significant improvements will be made in the former, even as the latter improves exponentially for the foreseeable future.
Protein folding, and more generally protein dynamics are not presently "solved", per se, but there is nothing "tricky" about direct physical simulation (the tricky stuff comes in finding shortcuts that speed up simulations while not sacrificing too much accuracy).
Ah but we do know what we are simulating. The fundamental physics involved are well known. It is the derived or 'emergent' behaviors which are too complicated for us to figure out presently, because we lack the number crunching power to just simulate the physics directly.
Posted by: Greylander
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August 22, 2010 6:18 PM
@ #287 Elladan:
Elladan, this is an excellent objection. You are correct that neither Moore's Law, nor various generalizations thereof are "laws" in the sense of "laws of nature". No one with any sense disputes this. There are, however, very good reasons to think it will continue for the next several decades.
Although we are approaching the minimum size of circuits on silicon, we still have a bit of room left "at the bottom" which will take us out for a few years. After that, even if no improvements are made at the chip level, cost efficiencies of mass manufacture will more and cheaper cpu's, which means we'll be able to have bigger "grids" or "clouds" of available cpu's networked together, which is basically all a supercomputer is nowadays anyway. So that buys us several more years. Then there are TSV's, putting 3-D chips on the horizon. Chips of a few layers are already made for special purposes. True 3D cpu's have some engineering hurdles, but none that are intrinsically impossible to overcome. Then there are many completely new technologies on the horizon or in prototype from graphene substrates and carbon nanotube substrates, to optical circuitry, to self-assembling molecular circuitry constructed from artificial DNA or RNA. These are not pie sky fantasies. The baby-steps of all of these technologies and more are already being developed in labs.
Yes, it is not a "law", there is no guarantee it will continue, but there is no good reason to expect it to end in the foreseeable future. Many good reasons to expect it to continue.
Posted by: kamil.pabis
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August 22, 2010 6:39 PM
I would describe myself as a "life extensionist" and even "transhumanist" and I regularly side with Aubrey de Grey et al.
Kurzweil, however, is rather controversial even among "us". His insane optimism (e.g. his timelines) and many of his statements sure give an unrealistic impression of and IMHO reflect poorly upon a good and necessary movement.
Many of his ideas range from insane optimism to frank idiocy. He *has* already been a let-down once when it comes to applied biology:
His "supplement regimen" for instance has been universally deemed useless to dangerous by those who actually have researched evidence-based ways to improve health or even extend life span by optimizing diet & supplementation.
Hence it would not be the first time that he displays a profound ignorance of biology or at least makes unjustified simplifications leading to wrong conclusions.
(usually I would not mention an author's prior mistakes [an argument should stand on its own], but most has been said on this topic and it is interesting that it would not be the first time Kurzweil et al. *seriously* screwed up their biology)
Posted by: Greylander
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August 22, 2010 6:42 PM
@ #286 Stephen Wells,
And yet, for all that, those little simulations do pretty a pretty darn good job. The same techniques will scale quite nicely with greater computing power. And with further accumulation of empirical data, the empirical force fields and other guesses can be filled in. Or additional computing power may allow simulation at a more fundamental level of physics so fewer empirically determined effects need to be included. Or a mixture (trade-off) of both of those along with larger models and longer sim-times.
You appear to know more about the state-of-the-art than I do, as well you should if it is your field. Since you bring it up, what is your role in that research?
Just think about what you are going to be able to do with computers a million times faster than today. A billion? A trillion?
Let's talk [generalized] Moore's Law here for a moment. If you dispute that, then we have a whole 'nuther discussion on our hands. But if you don't have a substantive disagreement with the expectation that [mere] "raw computing power" will continue to increase exponentially for at least the next few decades. Just think about the size and detail of simulations you will be able to run with computers a trillion times faster than the one's you have today.
Posted by: Nerd of Redhead, OM
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August 22, 2010 6:55 PM
Yawn, still more idiocy and missing the point by Graylander. What a loser. Hey Graylander, the argument has migrated to other blogs. Begone, and take your mental masturbations with you. Don't forget to wash up before you leave...
Posted by: David Marjanović
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August 22, 2010 7:47 PM
Long ago (well, about 20 hours), I wrote:
...and have already "identified critical flaws".
Anyway:
So far, so good...
Fine...
I think this assumption is why PZ called you "a fucking moron".
I do phylogenetics. To find all most parsimonious trees that explain a data matrix (a matrix of "species" and characters, consisting mostly of 0s and 1s) is an NP-complete problem if it's done by exhaustive search. Of course that's not done, because after 10 or more recently 12 "species" it would take forever. Up to 25 or so, branch-and-bound is used (I don't know how that works), and beyond that, heuristic searches are used: a somewhere-near-optimal tree is built by an extremely simple algorithm, and then it's rearranged millions of times to see if lower minima can be found. This way, dealing with a matrix with 102 "species" and 289 characters takes a day on a modern desktop, and increasing that to 110 "species" takes... two days.
It is still not linear. It's still exponential. The exponent is lower than for an exhaustive search, but it's still > 1.
And then, comments 250 and 286 come in.
You have no reason, other than random guessing, for thinking so.
That I want to see.
That circuit, it turned out, used what is called a parasite current. It relied on "it's not a bug, it's a feature".
Why do you think so? Why don't you think that the currently ignored effects increase exponentially with the size of a protein?
Posted by: Elladan
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August 22, 2010 8:03 PM
Greylander:
Right, we might imagine that the cost per compute unit of silicon will continue to go down as industry cost-reduces its fabs. Except hold on a second: even right now, when there's still some clear headway even just from die shrinkage techniques, we're already running into a power problem in large data centers.
Sure, perhaps the silicon will drop in price by half, leading to a doubling in compute power per dollar and so forth. Unfortunately, just making more chips cheaper means that your exponential growth in silicon is coupled with exponential growth in data center power. Given that data centers already consume over 1% of the national power grid, this can hardly keep going for long.
Perhaps you'll present reversible computing as a solution to this issue (despite the complete lack of any practical demonstration of it) or some other approach -- but come on. Look at your list of possible new technologies. Some of these might work. Or they might not. Or they'll work, but take twenty years of research to be of use.
How do you look at those and conclude, "well, these theoretical technologies will surely be available in time to maintain my desired exponential growth curve." ? It's all just exciting possibilities, not some sort of roadmap to exponential growth.
Our previous successes have for the most part been just due to continuing die shrinkage with photolithography techniques. We've had a run of amazing success at basically coming up with new ways to do the same thing smaller and smaller, but as you clearly know, we'll need to go in completely new directions soon to make further progress.
How you can see the future well enough to conclude that will result in the exponential increase in compute power per watt and per dollar that you've grown accustomed to, I have no idea.
Past performance is no guarantee of future results. It's true for technology too.
Posted by: Greylander
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August 22, 2010 8:19 PM
#285 KG Author,
KG, finally an excellent rebuttal. Or almost.
KG:
You start out (above) with what appears to be another fail based on a strawman. (Well it is that, but you get better below). You've seen enough of my "blather" to know that I make no claim that the brain is easily separated into hardware and software. Since nothing I've said is founded on such a claim, this gets nowhere.
But here we get to the heart of it:
Perhaps it will be an enlightening paper. I'll read it before I post again.
However, you may recall from from my earliest posts, previous thread, that in estimating the memory capacity needed for a simulation, I allowed as to that it could turn out that significant computation in the brain is done by molecular scale components (i.e. substantial leaned information stored in the detailed configuration/arrangement of molecules, as oppose to aggregates like the density of receptors on the surface of a synapse). This could explode the estimate by several orders of magnitude and set back the time frame several decades.
I've been busy rebutting absurd "counter-arguments" and gross misunderstandings (some from you, sorry, and you still didn't get much of what I said since you think the above is in substantial disagreement with me). And we've all been distracted by the "50 million bits"/information theoretic thing (after all that was what PZ's original post was about). So many people keep confusing that "50 million bits" with a Kurzweilian (or my) estimate of the total complexity of information in the brain it really muddies the water, since there are a handful of major points under discussion relating to simulation of the brain and how difficult it will be.
So let me be absolutely clear: Assuming there is no significant molecular-scale coding of information1 (as oppose to moleculat aggregates like densities/quantities of receptors, neurotransmitters, etc.), I put my estimate of the complexity of a living active brain at (ballpark):
10^18 maybe 10^19 bytes.
That is the estimate which takes into account all those "unique snowflakes" of which PZ is fond. The original article that got this all started had it at 10^16 bytes, which would be highly optimistic, I think, and I said so.
Go back and see my first or 2nd post, previous thread, lest you think I'm backtracking or changing my tune with out "admitting I was wrong". Most of you just don't get what the "50 million bytes" is about and keep raising specious objections... I'm tired of trying explain that distinction.
So let's just deal with one number. Say, 10^18 bytes. That is how big/complex the simulation will likely need to be. That's data plus executable code. OK? The "50 million bytes" issue is then just an issue of how much of that is "executable code" per se, and how much is "data".
Now back to your point, KG. The multi-level tangle you mention could indeed involve molecular scale encoding of information (again, as opposed to encoding in aggregate quantities and structures like # of recptors on a synapse). I find it highly unlikely that much molecular encoding, if any, occurs for a number of reasons, but mainly because it is just too messy at that scale. If the molecular-scale information is not stored massively redundantly, it is way to subject to random effects. On the other hand, if it is stored highly redundantly, then the information is not stored at the molecular scale, it is stored in molecular aggregates. Aggregates make a great deal of sense, especially for an evolved messy tangle, as they are quite stable -- and stability is quite important for storing information as anyone can attest who has suffered a power outage with unsaved work on their computer.
Even without significant molecular-scale encoding of information, I still allow for... let's see... about ten to one hundred million bytes per neuron. You can dispute the estimate or my reasoning behind it. You can insist that it still must be much much larger than that. But stop suggesting that I don't have an appreciation of the sheer complexities involved.
Like you and anyone else here, I can imagine even greater complexity... bumping up the estimate to 10^20-something. I can even imagine that the important stuff happens at the quantum level and then all best are off. But what evidence to we have for molecular-scale or quantum scale encoding? None, so far as I know. And before you contradict me, make sure you get what I mean about the difference between molecular-scale encoding verses aggregate encoding. Perhaps there will be some evidence in the paper you reference that will make me reconsider the above line of reasoning, but I'm not holding my breath.
Posted by: tylerofmanyminds
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August 22, 2010 8:44 PM
Greylander, I don't think you're being very transparent in the assumptions behind your complexity analysis. Exactly which problems are you referring to that only take O(n2) or O(n log n)?
Posted by: Greylander
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August 22, 2010 8:51 PM
@ #285, KG:
I actually attended a Genetic Algorithms conference in Vegas conference in which this, or a very similar result was presented, circa 2000. (anyway, I think that is when/where I saw it, if memory serves) Not at all what I thought you were pointing to... I was expecting something about the intricacies of the multi-level tangle that is our brain.
I assume that your point there is the very surprising way in which "disconnected" portions of the circuit were still relevant, ergo how we must then expect messy and unexpected interrelationships in squishy wet evolved systems as well. I do not disagree at all.
But do see my points about aggregate scale verses molecular-scale encoding.
Now, if someone discovers, for example, that inside each neuron there are extremely long strands of say, RNA which appear to have different random sequences from cell to cell, but for which no function could yet be discerned. Then, i would grant that such might be an example of a potential mechanism for molecular scale encoding. But even then, to approach the 100MB I've already allowed for an individual neuron, you would need RNA strands that begin to rival the genome itself in order to bump up my estimated information-per-neuron.
Another possibility would be if each neuron was discovered to have wildly different configurations of epigenetic factors, thus allowing us to posit a different mechanism for molecular scale encoding.
Have either of these possibilities ever been discovered? Anything along these lines? Have any neurobiologists suggested that they are possible let alone likely?
It would be really cool. I stand ready to change part of my tune.
Waving your hands and shouting "complex complex complex" just doesn't cut it.
Posted by: p
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August 22, 2010 9:02 PM
While peer pressure on this thread is getting Greylander to bend over backwards with generous estimates of how close to 10^20 operations per second it will take to simulate someone's brain, I think it's worthwhile to at least throw out an idea from the opposite direction: we're really not that smart. In fact, I wouldn't be surprised if a very carefully programmed current laptop could achieve human-level intelligence. I'm not, of course, betting that this will happen soon, just that, knowing how much my memory fails me, how often my intuition misses the almost-obvious, how long it takes me to do computationally simple tasks, I wouldn't be surprised if this could all be emulated with gigaflops to teraflops.
Perhaps the easiest way to get high numbers for human computation power is to look at the visual system, where we arguably have on the order of 10 million "pixels", and neurons react on the order of a thousandth of a second. So that kind of processing may be (slightly) beyond current laptops, but not by much.
Meanwhile, exceptionally well educated people still have a vocabulary around a hundred thousand; there's good evidence that one cannot concentrate on more than a handful of things at once. Most any task whose objective we can state precisely, abstractly, enough, laptop computers can beat humans at. (This is a somewhat shocking point... read it again!)
And, to forestall some of the standard objections that are trotted out: "what about deja vu? we clearly can remember lots more than we know of" Well, just because occasionally you remember something unexpected, just because occasionally you surprise yourself, doesn't mean your perceptive powers are 10^100 greater than they seem. I mean, my laptop occasionally successfully "undeletes" something too, occasionally surprises me (in a good way).
And, when I say "we're all kinda more stupid than we give ourselves credit for", please don't just say "speak for yourself", as I don't think that response justifies a claim that >10^20 operations per second of processing went into it.
Posted by: p
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August 22, 2010 9:08 PM
Oh, and, one more standard objection: "what about photographic memory?" Short answer: doesn't exist. There exist people who devote their whole lives to memorizing books, and, perhaps the best of these can memorize a few million words (10MB?). If photographic memory existed in any literal sense, the best memorizers in the world would be able to do way better than that.
Posted by: Greylander
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August 22, 2010 9:54 PM
tylerofmanyminds:
Nor problems. Algorithms. Simulation algorithms to be precise. Basically an N-particle system requires calculating and adding up the forces between each pair of particles, hence O(N^2), for example, for "all-atom" physical "ab initio" protein folding simulations, with N=number of atoms in the protein molecule. Shortcuts (one of the simplest being "ignore other atoms that are to far away from this atom to have a significant effect") can reduce this to O(N log(N)). Other techniques like "particle and field" could push this closer to O(N). This assumes holding everythign else equal, such as the sim-time and time step and numerical integration method used. More generally we would say that it is O( f(N) * T / dt ), where f(N) is one of the above, T is sim time and dt is time step.
Search algorithms must explore a combinatoric space of possible shapes. This is a combinatoric problem and has gawdawful complexity for obtaining a perfect optimal solution... but heuristic methods vastly decrease the time required while making the trade off that you don't see any of the dynamics and you may find local (or global) minima energy configurations that the protein can never (or rarely) actually get to -- you'll find "good solutions" which the may or may not actually be the shape the protein actually folds to.
A mixture of heuristic search and physical simulation will probably achieve very good results, and that is also done.
One thing I said possibly wrong earlier was that physical simulations will outstrip search methods... but heuristic search will also benefit from the speedup of computers, so whether this happens as a practical matter is another question -- it depends on the "big O" complexity of the best heuristic methods. Both have their strengths and when computers are a million or billion or trillion times faster than they are today... both methods will be drastically improved -- even if no one comes up with better heuristic or more useful empirical data in the meantime (both of which will be done, however).
Posted by: Greylander
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August 22, 2010 9:59 PM
@ #299 p:
Not caving, p. I opened long ago with the 10^18-10^19 bytes of RAM... it was more like 10^21-10^22 FLOPS. That was somewhat high-balling it. But Kurzweils 10^16 bytes and 10^17 FLOPS seems a bit too optimistic, even restricted to the cerebral cortex alone.
Posted by: tylerofmanyminds
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August 22, 2010 10:38 PM
Greylander, I'm aware that the n-body simulation only requires O(n2) in the worst case. Problem is, n-body simulations are only applicable where the forces acting on the particles are relatively simple. Protein folding is far more complicated than galaxy clusters being affected by dark energy. With protein folding, you also have to calculate the effect of rapidly moving solvent molecules and the thermal dispersion along the protein itself and the activity of the chaperon proteins and all the things we haven't even figured out yet (we still don't fully understand the process). I don't think a simple n-body simulation will cut it.
The basic flaw in your argument about simulation versus search heuristics is that you mischaracterize the effect of scaling with computing power. No matter how much computing power you have, as inputs grow an algorithm that takes log-linear time will always beat a heuristic with an exponential worst case if the inputs are large enough so that constant factors are negligible. Try solving a huge minimum spanning tree problem with the traditional greedy approach and compare the computation time to a suitable heuristic. The latter is guaranteed to take longer.
Posted by: Greylander
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August 22, 2010 10:40 PM
@ #295 Elladan:
Elladan, that is a good point on the power consumption. But that only impacts that mass-production angle, which I rely on as a worst-case scenario. And there are considerable energy efficiences to be sucked out of silicon yet.
Well... now that you mention it...
But seriously, there is nothing intrinsically energy intensive about computation. If nothing else we all agree here that our own brains are yet doing vastly more computation than today's supercomputers, while using the energy of a light bulb. You have to be an ardent pessimist to suppose we won't be able to find ways to compute with less energy.
I wonder how you look at those technologies and have much doubt? The essence of a computer requires extremely simple switching logic. You can do it with gears and levers. You can do it with vacuum tubes. With transistors. Hell you can even do it with appropriately water pipes (not kidding, I read a paper ages ago detailing a "water computer" proposed as a defense against EMP attack -- completely impractical for other reasons but interesting. Basically they showed what amounted to different shaped multi-pipe joints that acted like logic gates (and, or, not)).
None of these technologies relies on discovering new principles of physics. All of them are in their infancy, meaning they are beyond the "just an idea" stage. We know in principle they will work. Is it *possible* that none of these will be developed and have a significant impact for another 20 years, thus putting a kink in the Moore's Law timeline? Sure. I'm not claiming there might not be "bumps" along the way. It is also possible that after your 20 year dry-spell, once the new technology does come online, the exponential growth will explode even faster.
As I've said before, I have no argument with anyone who just wants to multiply my time line by a factor of 2 or 3, at that level there lots of wiggle room for unpredictables and intuitive hunches. If you want to push back the timeline by a factor of 10... push it out to centuries, millenia, or "never"... I still cannot "prove" that you are wrong, but in that case I think you're just kinda blind. I see it. You don't. Maybe I'm deluding myself. Maybe you lack vision. Shrug.
Posted by: Greylander
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August 22, 2010 11:05 PM
#303 tylerofmanyminds:
Wrong. Complex forces may require more calculation per partical pair, but that just goes to the constant factor not to the n2.
Yes... but being able to handle more particles means we can also include solvent molecule and chaperon proteins as part of an "all-atom" simulation.
A big part of the point of a physics simulation is that we need to understand much less -- we run the sim and see what happens. Before someone jumps on me, this does not mean that we don't make use of empirical data when and where we can. Whether to simplify the sim or to verify it. In other words if you can get good empirical estimate of the force fields of a monomer, then you might choose to treat the monomer as a single particle in your sim rather than dealing with the atoms that compose it.
Um... the greedy algorithm *is* a heuristic. I'm not sure but you might be confusing heuristic algorithms with algorithms guaranteed to provide perfect solutions (though they may take forever and a day). At any rate, the time complexity of any heuristic algorithm is going to depend on the particular algorithm. Greedy give "ok" answers and is O(N). Heuristics that give better answers will typically have worse time complexity, like O(N log(N)), O(N^2) or O(N^3) or whatever.
Posted by: tylerofmanyminds
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August 22, 2010 11:42 PM
"Wrong. Complex forces may require more calculation per partical pair, but that just goes to the constant factor not to the n2"
I'm not talking about complex forces, I'm talking about forces that can't be quantitatively handled in an n-body simulation. N-body simulations can only calculate forces between particles that can be accounted for by integrating differential equations. If you only want to account for electrostatic and van der Walls forces, that's fine (some protein folding simulations formulated as n-body problems do just that, but it doesn't encompass all the relevant details).
"Yes... but being able to handle more particles means we can also include solvent molecule and chaperon proteins as part of an "all-atom" simulation."
They would be subject to different forces than the amino acids themselves, so they would have to be dealt with in a different pass (a separate n-body problem).
"In other words if you can get good empirical estimate of the force fields of a monomer, then you might choose to treat the monomer as a single particle in your sim rather than dealing with the atoms that compose it."
This is a ridiculous strawman. I never said that you have to simulate all the atoms of the system. What I said was that there are well known global aspects of the protein folding process that we don't understand. Simulating protein folding accurately requires understanding them.
"Um... the greedy algorithm *is* a heuristic. I'm not sure but you might be confusing heuristic algorithms with algorithms guaranteed to provide perfect solutions (though they may take forever and a day)."
You are mistaken. Greedy algorithms are correct for problems that are matroidal. MST's are an example of such a problem.
Posted by: Elladan
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August 23, 2010 12:31 AM
Greylander:
So now research technologies being in their infancy is a good thing, and implies that they'll surely work?
And... after a 20 year dry spell, exponential growth will somehow be maintained? Computers will stagnate for a few decades, and then we'll just suddenly figure out how to make them 8000 times faster?
You need to step back and take a good look at what you're arguing. You're arguing for exponential growth. This is the basis for your belief that you can make some sort of projection where you assume that piddly factors like O(n^2) just aren't so bad.
I'm not saying that boom, 2020 comes and we never develop a faster computer. I'm saying that you have no basis to assume that somehow future developments in computing will magically conform to some 18 month doubling rate so as to make your ideas of the future plausible.
Perhaps we'll figure out how to make computers ten times faster in 2017, and then they stagnate for 30 years before hiccoughing a 3x improvement and stagnating again. Perhaps computer engineering becomes a backwater for a hundred years, the tales of advance the dreams of youth, surely dashed on the rocks of turbulent history, while one doddering old beardless professor and her bright young grad students slowly and doggedly keep at it working on the next big advance until finally the ancient dream of 3D nanoelectronics becomes a reality in 2150 and we see another dozen years of advance before that avenue too becomes stagnant.
What specific technical roadmap do you see that will lead development to follow a tick-tock metronome of exponential growth? Which early research technology will we be using in 2019? 2025? 2030? If you can't answer that, why do you feel competent to predict how fast computers will go? Why do you think exponential growth is even reasonable? Why not geometric? Why not logarithmic?
You're just making a pure assumption here. You assume that when we run into problems, we'll solve them in a few years. Why? Perhaps it will become harder and harder to solve them, such that each new advance follows a long and arduous slog through many years of basic research.
You want it to be true. So do I -- it sure would be handy to have a cell phone that doubles as a cluster supercomputer. But we can't always have what we want, and we don't know what the future will bring.
Posted by: Greylander
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August 23, 2010 1:17 AM
@ #306 tylerofmanyminds:
We're likely the only two left here but anyway...
Last things first.
Facepalm. I stand corrected on that point. Been over 20 years but I had to prove that myself once. But in this case, I'm not sure what you are getting at with the MST example. In general heuristics sacrifice optimality for time complexity... so your example of heuristics with worse complexity made little sense in the context. I suppose there might be heuristics (or not necessarily even heuristics but perfect algorithms) with worse O(), but much much better coefficient or at east much better time on average ordinarily even though they have horrid worst-case. Since we are talking a problem with combinatoric complexity, I'm going to go with the heuristics that trade optimality of solution for dropping O() (whether average or worst-case) to polynomial or better. And such will benefit nicely from faster computers.
"Wrong. Complex forces may require more calculation per partical pair, but that just goes to the constant factor not to the n2"
Are you talking about field dynamics? I don't think you can mean the electromagnetic field (you don't seem to suggest it), as propagation there can be considered instantaneous at these time&distance scales. Perhaps you mean some kind of field which approximates the effect of the surrounding solvent without modeling individual molecules or atoms. I think very worst case there might be that the volume simulated might need to be as much as O(N) so the simulation of your dynamical field might make your overall simulation O(N^3). But granting you O(N) volume is a big concession. I can already think of reasons that should not be necessary.
If you have something else in mind, I need an example.
I don't follow your thinking here. Each pair of particles might require a different force calculation depending on types of particle. I see no particular reason this requires a whole separate simulation -- the whole point is to simulate them all togethre so they interact. This is still going to be O(N^2) (or whatever is required by your "complex forces").
You misunderstand me. If anything I am proposing the all-atom simulations. After all, they are already being done for "small" proteins.
Can you elaborate on "global aspects"?
Posted by: KG
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August 23, 2010 3:57 AM
Greylander,
Crap. You said quite explicitly that both neural activity and the fine structure of the brain are software. They are nothing like software: you can't copy, edit, compile, or run them, and there is no "programming language". It's not a question of not being able to "easily separate" the brain into hardware and software: the distinction simply has no application to the brain at all. The brain is not a computer any more than it's a telephone exchange - the pre-computer metaphor. This was the fundamental error of GOFAI - an error to which, I may say, I subscribed for a decade and a half.
You have missed the point of the Thompson paper. The point is, that the solution arrived at by the GA worked as it did because of the detailed physical properties of the hardware used to implement the circuits - when these were changed, it was no longer the best solution. The solution was not the outcome of any limited set of "basic operations", such as you and Kurzweil believe in for the brain, and the search for a set that will explain the brain's capabilities will almost certainly fail, because, like the GA in Thompson's paper but to a far greater extent, natural selection will have produced a "solution" to producing a real-time problem-solving and decision-making organ working in conjunction with a body and an information-rich external environment, that will make use of the physical properties of that organ, and of the body and the environment, in ways we will have to understand in detail - and contrary to your extraordinary naivete, that is not just a matter of collecting more data. Look at what the FAQ for the Blue Brain project says, or what Markram says in peer-reviewed papers like this one, rather than when showing off to the popular press. Here's the abstract:
This kind of brain modeling is good, useful science, but it's not even intended to produce a functioning AI: it's a research tool to be used in a long and painstaking research process of understanding.
As far as I'm concerned, the total computational complexity of the working brain (in fact, I doubt this phrase actually has any useful meaning) is not the obstacle to near-term brain emulation (so trying to show its 1018 bits or whatever you claim it is, is not relevant): the obstacle is that we do not have, and will not have for a long time, the knowledge we need to do it. Not just data - understanding. Just as - in an example I used before - the remarkably rapid completion of the human genome project has so far produced practically nothing of value for clinical practice or even applied medical research.
I agree that the arguments about the genome are to some extent a side issue, but you're still completely wrong, as is Kurzweil. Let me try from a different angle. According to you, almost all the Kolmogorov complexity of the "design" of the neonate brain is in the genome. Now, I hope you'd agree that (if Kolmogorov complexity has any useful application here, which I don't believe it does), the whole biosphere must contain at least several orders of magnitude more of it than a single neonate brain. Where was all this Kolmogorov complexity 4.5 billion years ago? After all, you've dismissed the idea that information from the environment can contribute "in any worthwhile sense" before the brain starts actual learning.
Posted by: KG
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August 23, 2010 5:23 AM
Two minor corrections:
1) "computational complexity of the working brain" should be "computational power...".
2) As I've said before but should probably repeat, I'm not saying GOFAI is useless, in either science or engineering applications. I'm saying the assumption that a human-like intelligence could be developed by "skimming" and implementing a software-like symbol-manipulating level was an error.
Posted by: grudgedk
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August 23, 2010 9:21 AM
http://wordnetweb.princeton.edu/perl/webwn?o2=&o0=1&o7=&o5=&o1=1&o6=&o4=&o3=&s=artificial+intelligenceNo it isn't.
You realize of course that Ray Kurzweil is a Unitarian, right? I'm pretty sure that's John Von Neumann, not Marvin Minsky. You mean meme-parroting fools like Bachelor of Science in Computer Science and Literature, Ray Kurzweil? Citation Needed!Posted by: Greylander
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August 23, 2010 9:33 AM
Obviously in context of a developing organism "information from the environment" refers to the current environment impacting the developing organism. Information from oh, say just 4 years ago, is not going to have any effect on the organism today unless you are talking about light from alpha Centauri, to invoke your light cone. 4.5 billion years of evolution has done a pretty good job of incorporating information into the genome. I'm not sure where you are getting "information in the present environment does not appreciably alter the fundamental structures/processes of the organism [as opposed to contributing to its innate plasticity]" is equivalent to saying "the environment over the past 4.5 billions years has not contributed information to the organism". It has. The genome encodes lots of trial-and-error information about how to replicate itself in past environments.
10^8 bits is nothing to sneeze at, despite the fact that we all watch compressed movies with files that require ten times that much. We obviously mean very different things by the phrase "separating the hardware and software of the brain" (or whatever), but setting that aside, my 10^18 (as opposed to 10^8) is where all the information from the environment, as experienced by the developing organism, goes.
Another way to state the point about the genome would be to say that, in rough terms a 10^8 bit program plus a gazillion bits of data from the environment as input goes into creating the 10^18 bits of information content of the brain. And 10^18 bits is only the cognitive info. I think we both agree that something like 10^30 or more is require to specify every atom and electron and lets not even go to quantum state.
It seems to me that your claim amounts to saying that figuring out what the ~10^8 bit program is (or most of it) is just going to be too damn hard to achieve in the next 20 years. And perhaps you also mean that if we only get 99% of it, then that is still somehow a total failure, because that last 1% is still going to be extremely crucial to the problem.
Part of the issue here may be that what you and many on your side have in mind for the 2030 prediction is a level of knowledge of brain that equates to being able to achieve the fabled "upload" (or is it "download"?) in 20 years. I'm not defending the "upload" thing or anything even close. I've barely read anything by Kurzweil, but I'm pretty sure the brain-simulation-by-2030 is not referring to the upload capability -- not talking about copying and simulating a living brain at that point -- not really even close. I *think* Kurzweil has in mind that life-extension technologies may give him the extra centuries needed to reach the "upload" stage. "upload" or copying of consciousness itself is right on the boundary between "scientifically possible in principle" and "pure magic".
I also would not expect the 2030 era brain simulator to pass a Turing test -- it will be glitchy and imperfect. We won't have a good way to give the "initial conditions" so it won't have any normal sort of memories to start with. We won't have the capacity to simulate development from the egg to the brain, so we won't be able to make the initial wiring look like a baby's wiring except maybe in a vague statistical sense (on the other hand, much of a babies wiring might be somewhat randomized as an initial state, so that might be ok). I expect that the simulation will start with somewhat random wiring, but it will operate under the same (or a close approximation) rules governing self-modification (growing/pruning synapses) and so it will be able to learn. I expect that for quite a few years after reaching the raw ability to do a decent simulation all we will end up with are more-or-less "mentally challenged" (low IQ), insane, or brain-damaged (or all three) sorts of simulated "minds". These simulated minds might be able to learn enough to interact and communicate on some level, but lacking any ordinary human experience, they may seem quite alien. Over the course of another few years we'll shake out the bugs and have even more simulation capacity, and have had time to let the sim-brain develop and learn in real-time, so we eventually have a simulated mind that will understand more or less its own nature as a simulated brain and able to communicate that level of self-understanding to us. My "prediction" if you want to call it that is that by around 2060-2070, we could have a simulated brain either in or wirelessly connected to an artificial human-like robot body (or succession of bodies from baby to adult size, or possibly a genetically engineered biological human-like "robot" body). It would be able to develop in a roughly "human" manner, but almost certainly aware of it's own nature and therefore still rather "odd" personality-wise.
We'll probably have GOFAI as you call it before we have the latter degree of human-brain-simulation.
I think it will be centuries yet before it is possible to do anything seriously resembling the capability to "upload" the complete information-state of a normal organic brain, but I also think that by that time such an ability would be superfluous -- we (or more likely our near term descendents) will have been so enhanced by genetic engineering and cybernetic integration, we won't care much about those original chunks of grey-matter.
I'm sure clarifying my own "predictions" here won't matter horribly much, as most of you would replace my decades with centuries, millenia or "never".
BTW, KG, for all the "you're an idiot" jabs (mine as well) of our first exchanges, I feel like we're actually now having a rational exchange on the subject. Appreciated.
Posted by: Greylander
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August 23, 2010 10:33 AM
@ #279 Kristjan Wager,
What is a "non-trivial" number? Perhaps you mean "very large"?
If computers get faster exponentially with time, they will inevitably conquer a linear complexity problem. You may suppose that c and k are extremely large so that it will be many years before exponential improvements in speed make a noticeable dent.
Unfortunately for you point we already have simulations for "smaller" values of n. So we know that c and k (in your example) are small enough that today's computers can run those simulations in reasonable amounts of time. However fast they run today, they'll be that much faster tomorrow... or we can run for on larger values of n.
Please, please tell me that O(1^n) is a typo. You do realize that that is just O(1), right? I think maybe you meant e^n?
You don't really seem to have taken in the context here. I'm not talking about computers solving any arbitrary problem. I'm talking about computers running physical simulations of protein molecules specifically.
So, in other words, the focus on some sort of upper bound of O(n) or even 0(n^2) is of course just a random upper bound picked by Greylander.
Posted by: Thomathy
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August 23, 2010 12:14 PM
I'm finding it very difficult in this discussion to move past the words 'from baby to adult' or the implicit belief that brains don't learn or think while they are developing. Language learning begins in the womb in humans. Recognition of the mother begins in the womb in children (as a concurrent result of language learning). The developing brain (and I mean that quite literally) is in the process of functioning during development and continues this process to the end of life.
It seems to me that there is a fundamental misunderstanding of the nature of the brain and how it is grown (develops) by some of the people in this discussion.
It is trivially true to say that DNA provides some sort of code from which a cell might be born of an extant one, but DNA contains no information about anything that that cell might one day do. The functioning of a cell is determined by its interaction in the developing organism with other cells through chemical signalling and like processes. The DNA is certainly not a blueprint -at least not in the way it might be thought to be- and it's just not going to be possible to extrapolate from DNA what that initial cell is going to eventually develop into, except to say that it will develop into a cell of whatever species that DNA represents.
It's terribly important too, to recognize that the cellular component is absolutely necessary. That initial cell with that DNA in that environment within the womb is 'being told' what to do, to split at the appropriate time, and those two cells to then again split and form whatever structural patterns give rise to further stages of development not only from the DNA within that cell itself (that cell already being functioning), but from the interaction in that environment, literally with the cells of the mother's body and her hormones and all those chemical signalling pathways. These processes cannot be separated.
All of this has to do with the salient point that I'd like to make: the brain is never a blank slate. At no point in its development, at least as a recognizable brain, is the brain not doing something (of course it's doing something before it's a recognizable brain, but I wouldn't want to call that anything like learning or 'working', because it's still formative). The brain must necessarily be doing something during its development because there exists in humans the extant pattern there in the brain that provides the framework by which language is learned (a process we really, really do not understand -like so much else). This is all to say that the brain functions before we're born and I think that's important.
Nothing that the brain does however is literally not in the DNA and can't readily be extrapolated from it. And the process that developed that neuronal pattern that facilitates language learning is not merely a product of what's contained in DNA. Nor is it necessarily sufficient for functioning that those neurons are only structurally patterned the way they are, they also have to interact in particular ways with each other and with other neurons and deeper than that each cell must interact with every other cell, even with cells that are remote from it. The brain, further, is part of a dynamic system that is the entirety of an organism. A brain does not function independently of the sensory organs or the spinal cord, indeed it's quite accurate to say that the brain and the rest of the organism are inextricably linked extensions of one another every part of which is interdependent and codependent.
So, when it comes to reverse engineering the brain, well, I just can't see that it can happen in any particularly useful way as it's being discussed. So what if we take any given human brain a recreate it structurally? For that structure to work you must also recreate the way the components of that structure interact with each other on all the myriad levels that they do, and not forget that the nervous system and all the sensory organs are a part of that brain, indeed that the body is a part of a dynamic system that is inextricably linked to the brain and the brain to it. It all functions as one piece working together. It seems to me that recreating an organism virtually (indeed, in this case we're talking about a human) would seem to be incredibly difficult to accomplish and considering we're not even close to starting I can't see how it's possible given the time frame espoused.
And I really can't see what relevance at all DNA, or the amount of information it has, has to do with that at all. Are we talking about growing a functioning brain (really and entire organism) from some DNA, all of it virtual with all of the hormones at the right time and right amount virtually programmed and all the cellular communications virtually programmed? I can't see how that could be possible given we don't even understand, as has been pointed out, how exactly cells communicate with each other or, importantly, what importance it has. The brain is not like a piece of machinery that can be taken a part and analysed to see how it works. I'm going to go so far as to say that the idea of reverse engineering the brain is a fallacious concept -at best.
Posted by: tim333
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August 23, 2010 12:20 PM
From a Kurzweil fan:
In 1989 he predicted a computer would beat a the human champion in 1998 and it actually hapened in may 97 - so not bad there.
Brain reverse engineering is already happening and will probably pan out roughly on the preditced time scale.
I don't know whats with the "kook kook!" negativity here. Are there any intelligent engineers on this thread?
Posted by: Thomathy
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August 23, 2010 12:27 PM
It is trivially true to say that DNA provides some sort of code from which a cell might be born of an extant one, but DNA contains no information about anything that that cell might one day do.
I didn't mean quite that. Of course, the DNA contains information relevant to how a cell will function, but the DNA doesn't know where that cell will be or what chemical signals will cause that cell to 'read' or 'not read' those parts of the DNA that determine its functioning. The DNA doesn't contain, in other words, any plan for that cell only minimalist instructions for it to follow to perform it's functions as a cell of a particular type.
Posted by: Nerd of Redhead, OM
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August 23, 2010 12:31 PM
Finally, a cogent comment on the actual biological science by Thomathy, instead of computer shit that Graylander the verbose, persistent, and clueless spews, which is totally irrelevant to the science. Even if a computer becomes sophisticate enough to do AI, you still have the problem of the science for both reading the mind at the nanometer scale, and determining how to write that into something, either wetware or silico-hardware.
Posted by: llewelly
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August 23, 2010 12:50 PM
DNA could be viewed as a program, whose behavior is strongly dependent on its input. Oh, yeah, and something like 80% of runs end in fatal crashes less than 1 month after fertilization ...
Posted by: CJO
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August 23, 2010 2:17 PM
Greylander:
So I made a model that predicts the weather a week out, but it doesn't look like the actual weather except in a vague statiistical sense.
What would "the same weather, in a vague statistical sense" look like?
PZ makes the same basic point in the OP:
There are no "generic" brains, just as there are no such things as generic turbulent flows or generic weather. The particularity is all, and any fudges or errors are going to cascade in an inadequately fine-grained simulation, butterflies in Brazil and all that.
Do you see what's wrong here? Do you see that all the problems, and your blithe waving them away, are encapsulated in phrases like "in a vague statistical sense" and "the basic principles of operation"? Brain development is like turbulence, or the weather, with sensitive dependencies all over the place, and a simulation of it content with vague statistical fudging at our gaps in understanding is going to return garbage. Why hasn't the massive, exponential increase in computing power since the 1960s solved fluid dynamics, Greylander? What is the barrier to weather simulations that make accurate long-term forecasts? Answer those questions and you'll understand (some of) the objections to your approach.
Posted by: tim333
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August 23, 2010 3:21 PM
For those interested in the actual progress on brain simulation check out the Bluebrain Year One documentary preview - pretty interesting, even for the Kurzweil haters I think.
http://thebeautifulbrain.com/2010/02/bluebrain-film-preview/
Posted by: KG
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August 23, 2010 3:53 PM
Greylander,
OK, so we’re agreed that information doesn’t have to come in even the quasi-digital form of the genome to contribute to the formation of complex structures.
So what do you mean by it?
But you appeared to be claiming that very little of this was taken in before birth – that (presumably) almost all comes in the form of sensory input between birth and adulthood. That’s an error. First, the growing brain (like the rest of the embryo) requires quite precise levels of a considerable variety of nutrients if it is to survive, even more precise if it is to thrive, and even within that range, differences in what comes in through the placenta (or in the case of a bird, what gets added to the egg as it forms within the mother, then gets into the embryo from the yolk sac, probably make a difference to how many of what kinds of neurons and connections form, what the balance of neurotransmitters is, etc. Now you will say “But the rules for this are in the genome.” Not so: the genome is not a program. As I’m sure you know, multiple parts are read simultaneously – and which are read in what order, and what quantities of RNA and protein are produced, depends on the chemical environment within and internal structure of the cell – in turn affected by the extra-embryo environment. The genome, in short, can be “read” in a huge number of different ways, and which of these is realised is not and cannot be specified in the genome itself. Second, the brain does not start learning at birth. It begins to learn as soon as neural impulses can pass. Why do you think babies move in the womb, and chicks in the egg? It’s not just about developing muscles, but the nervous system. The embryo also has senses of touch, taste, pressure, proprioception and hearing – so even if you exclude non-sensory information, you have to talk about the (human) brain not at birth, but at about 20 weeks, when it is a far less complex structure, being formed without learning.
No: it’s not a program and you can’t understand it without understanding the environment in which it develops.
Here’s the Prophet Kurzweil (May He Be Uploaded) himself, p.324 of The
Holy ScripturesSingularity is Near:He goes directly on to say:
Clearly, however, he sees uploading as one way he will have of escaping death, if he lives to his late eighties or early nineties.
The rest of what you say looks to me like pretty empty and pointless speculation – unless as the basis for an SF novel. We have no idea what 2060-70 will be like. Quite likely, nuclear or biological warfare, or environmental disaster, will have destroyed civilisation by then. Even if not, we may well be struggling desperately to prevent such an outcome. If not that, we have no way of telling what direction technology will take – and this is not something that will be determined solely by what is possible. Consider what might have been done by now in terms of human colonisation of the moon and nearby space, for example, or in terms of reliance on nuclear or solar power, if the resources had been put into those technologies. One thing we can do is look back at how technology has developed in the past. It’s not at all obvious to me that technological change is speeding up, as it affects most people. The only big difference between now and 50 years ago in these terms is the prevalence of computers, mobiles, and the web - ICT. Between 50 and 100 years ago – massive expansion in road and air travel, television, nuclear weapons, cruise and ballistic missiles, tanks, huge dams for hydroelectric power, artificial satellites, antibiotics. IT has grown so fast because that’s where the combination of relatively easy gains, and R and D money, has been. And note that many of the predicted advances in ITC – particularly in robotics, AI and related fields – have not happened, because they turned out to be much, much harder than the techno-optimists predicted. Almost no-one saw that the most generally useful thing you could do with a computer – was to connect it to other computers.
*He means via nanobots in the brain.
Posted by: jvospost3
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August 23, 2010 6:26 PM
I was known as a Futurist in the late 1970s and early 1980s, when I was writing those Omni Magazine cover articles. But I split myself into someone publishing real Science in refereed conferences and journals, and someone openly putting the fun ideas in Science Fiction.
With all due respect to the bubbly and glib Ray Kurzweil, who even my little brother likes, one needs to know the difference. I can enjoy writing Singularity Science Fiction without being brainwashed into the Cult of Singularity by a talented inventor who seems to literally misunderstand the exponential function, and ignore the Logistic Curve.
I left A.I. after my 1975 M.S. in the field, because of all the Computer Science geeks who were willfully ignorant of actual brains, animal and human.
Posted by: imnotandrei
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August 23, 2010 7:45 PM
I may be missing something here -- but there's an elephant in the room that seems to be being omitted.
Unless you are talking about enough computing power to accurately model the N-body problem that is the human brain at the atomic level -- not the molecular level, and certainly not the "neuron" level -- you're not going to get a proper brain-simulator. Because brains aren't, and have never been, discrete-state machines.
I worked with Victor Yngve in the late 80s-early 90s, when he was working on an attempt to model human linguistic patterns using a computer model; I eventually gave up that approach when it became clear to me that trying to simulate a fluid system in a discrete-state manner simply was not going to work.
I won't pretend to do the calculation on what it would take to simulate even the firing of a single neuron at the neuro-transmitter level; I am not a biologist. But I do know that unless your model of the brain can account for the neuro-transmitter level of action, you're not going to get the result you want.
(As a side note; to defend our host's analogy regarding doublings -- the presumption in the "if it takes 25 years rather than 20, you'll still get a million dollars" is that in those 25 years, your bank hasn't failed, the currency hasn't been devalued, and the aliens haven't taken us all away to become enzyme farms. ;) He wasn't arguing the math, I believe, but rather the dependencies.)
Back in the 1980s, William Gibson presented us with an example of an "encoded personality" on digital media. Which always responded the same way to the same stimuli. Exactly the same way.
Which is what you'd expect from a discrete-state Turing machine.
And not from a brain.
Posted by: BrianX
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August 23, 2010 9:27 PM
Tim333:
Except that it turns out that chess is not the AI-advancing problem people thought it was -- more than anything else it's a game of memory and anticipating your opponent's choices. Chess lends itself very well to computerized players, to the point where computerized chess is very close to being a solved problem.
In other words, Kurzweil had every reason to assume that a chess computer would beat a human in the foreseeable future. However, it's not a good analogy for brain modeling.
Posted by: BrianX
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August 23, 2010 9:45 PM
jvospost3:
Ah, I see... so even then, the relationship between AI and cognitive science was, at best, adversarial.
Posted by: Greylander
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August 24, 2010 12:00 PM
KG:
Without going back and re-reading everything, I'm not sure I'm the one who first used that phrase. In any event, the notion is at best a metaphor. I have made the point that the brain codes information in the obvious physical structure of the "wiring" of neurons by synapses. This, and similar facts, is a great source of miscommunication in this entire discussion, because people want to equate "wiring" with "hardware". Since all information must be encoded in some kind of physical structure (even in computers electrons and electromagnetic fields must move and change from one stable state to another, and that is just as "physical" as growing a new synapse) the distinction between "hardware" and "software" is irrelevant.
In principle the following could be constructed, with time money and a perverse sense of computational masochism: A CPU ("hardware") can run a binary executable program that instructs it to read and execute the instructions in a textual programming language (say Pearl) which instructs it to read and execute the instructions in another programming language (say Lisp, just for perversity) that instructed it to read and interpret a file specifying the design (logic) of an massively complex electronic circuit, generate an actual circuit layout instructions for an automated manufacture facility to construct the circuit (chip). The constructed circuit could be something that accomplishes *everything* outlined above but does it all "in hardware". Each program above may be "software", but they are physically encode by configurations of electrons and electromagnetic fields in the circuitry of the original cpu & its memory... so each stage of the process above could be regarded as "hardware" running the "software" of the next stage.
From a purely computational theoretic point of view the distinction between hardware and software is arbitrary.
This is a completely different claim than that the environment adds information to the "program" (as opposed to the data operated on by the program). And no one ever claimed that we could reverse engineer the "program" (again, loosely speaking, the differential equations, or a bit more precisely the time-evolution equations) without studying how cells and cellular machinery interacts with their environment.
The straightforward brain-porting scenario involves scanning a human brain (most likely from within*), capturing all of the salient details, and reinstantiating the brain’s state in a different – most likely much more powerful – computational substrate. This will be a feasible procedure and will happen most likely around the late 2030s.
That quote looks pretty damning. I certainly appear to stand corrected, re: what some on the Kurzweil side have said. He does say "late 2030's" so he is allowing an additional ten years to reach this point. He may have been being flippant or off-the-cuff in that quote, since I have seen other quotes or paraphrases that seem to contradict this and put his timeline for "brain-porting" much further back.
However, the focus of these past two Kurzweil threads have been the relationship between information in the genome to size of executable code portion of a brain simulator, and secondarily on whether "accelerating technological advances" will get us to such a simulator by circa 2030. The original referenced article makes no mention of "brain scanning" or "uploading/copying" or whatever. And Kurzweil, in his response says "...I said that we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation..." which is quite different from the "brain-porting" mentioned above. I have kept my own discussion almost entirely in the domain of the original article, and PZ's very flawed critiques.
Kurzweil may be exceedingly over optimistic. He may have slid into quack-land when it comes preserving his health. I'm not here to defend him in particular or generally. I'm defending particular ideas.
I came up with singularty-ish ideas long before I ever heard the term or heard of Kurzweil.
"Empty and pointless" is a subjective opinion. All predictions inherently carry varying degrees of uncertainty. My "predictions" are considerably more certain than, say predicting that all people on the earth will turn into pink unicorns on Jan. 1, 2012, just before a giant asteroid strikes and destroys the planet. And 2nd half of preceding example. Predicting that we will have computers approximately a thousand times faster than today's in 2020 is vastly more likely than either of the preceding. And so forth.
You say that and the immediately contradict yourself:The above is a prediction, based on looking at trends in industry, economy, politics, and on intuitions about human nature. You might be right. Is this a pointless and empty speculation useful only as the basis for an SF novel?
Major global catastrophes, man-made or natural would of course delay or bring an end to my timeline. I'm already accused (with merit) of being too wordy... but I try to avoid increasing my verbiage to add obvious caveats or exceptions.
"No way of telling" is pretty broad. We can look at present trends, economic incentives, political/social pressures, available resources, and what is in principle possible. This allows predictions that are somewhat less than a "law of nature" but somewhat more than an "educated guess or speculation".
It is entirely obvious to me.
(1) a great deal more has changed. Think about this a bit more and be honest with yourself. I'm not going rattle off a hundred examples.
(2) Even the above changes you dismiss with the word "only" as if to imply "mere"... These things alone are incredibly radical changes in terms of there impact. The incredible ease with which 6,000,000 of us can now communicate is the greatest hope we have for "world peace" and cooperation in the face of potential global catastrophe.
The above kind of things have continued to massivly expand -- even faster, in the last 50 years.
Yes economic incentives and practicalities will always matter. The universal usefulness of ever more computing power guarantees there wil always be economic incentive. As to understanding the brain ... that falls under research into human health in general, something for which there will always be strong demand and economic incentive as long as there are humans.
Some singularity fans come along and talk about how nay-sayers were wrong in the past, and the anti-singularitarians say that proves nothing.
Likewise your example of failed optimistic predictions proves absolutely nothing.
Some predictions are better than others. Some people are better than others at making predictions. Assuming we are not talking about predictions of non-chaotic systems with well known initial conditions governed by well known laws of nature, then the predictions must necessarily be qualified with some sense of "probability" and some amount of educated intuition is going to be involved. This does not mean that the predictions are pointless, uninformed, baseless "woo". There is plenty of room for smart people to wildly disagree without any of them being ignorant or irrational.
Posted by: Greylander
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August 24, 2010 12:04 PM
[oops forgot the check all my blockquotes in preceding... it's not too hard to sort out though... and since KG probbly only one to read it at this point... if even him...why oh why am i even worried about it... lol]
Posted by: David Marjanović
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August 24, 2010 12:11 PM
Nope. I just found you in the list of the 10 most recent comments, so I'll try to catch up now... :-)
Posted by: Greylander
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August 24, 2010 12:21 PM
#323 imnotandrei,
imnotandrei, I think you are unfamiliar with numerical integration of differential equations. Discrete simulation of systems that have continuous variable is not only possible, it is done all the time. These simulations produce "approximate" results, but can be extremely accurate. The accuracy basically depends on how much number-crunching (computation) you can to in a practical amount of time for practical cost, and upon how complex the thing you are simulating is.
Let me repeat to be clear: discrete state machines (computers) are used all the time to very accurately simulated continuous processes.
Where do you think weather forecasts come from?
I just shivered. I think your phantom elephant in the room just walked through me. :)
Posted by: Greylander
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August 24, 2010 12:51 PM
#328 David Marjanović:
Hadn't thought of that. I don't usually notice the "latest comment" section. Usually I follow a thread until I close the tab it's on in firefox -- hit reload once in a while when I want to see if the conversation has progressed.
I wish ScienceBlogs provide a more forum-like comment section, and an actual forum (every blog post could automatically generate a new thread in the forum -- and that thread should be one and the same as the 'comments')
Posted by: CJO
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August 24, 2010 1:19 PM
Would you characterize weather forecasts as "very accurate"? (Without making a value judgement; it seems to me that the accuracy you're claiming for the future ability to simulate complex development processes would be analagous to looking at a tropical depression in the Atlantic and being able to say with confidence where on the Gulf coast and at what stregth a storm will make landfall, clearly outside of the scope of current weather simulations.) So why hasn't long range weather forecasting increased in scope with the exponential growth in computing power since simulations began to be used to predict the weather? Could it be that dynamic systems exhibiting sensitive dependence on initial conditions resist simulation via brute-force computation?
(I brought this up in a recent comment, so I reiterate my point since you mention weather forecasting apparently independently.)
Posted by: KG
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August 24, 2010 2:54 PM
Greylander,
Very briefly, I think we've about reached the end of useful interaction. If you want to talk about "rules" for how the genome is read at all (which is misleading), they are distributed across the genome itself, the contents and structure of the zygote, the mother, and the external environment. The point about natural selection is irrelevant, because the genome has evolved to make use of a vast amount of external information it can "expect" to find, which you will not have in a simulation. PDEs are not good at dealing with things like the membranes and organelles of the cell, which act as catalytic sites and reconfigurable filters. It's simply bizarre to say that the software/hardware distinction is irrelevant: the former, but not the latter, consists of strings of digital information - and there isn't any of that in the brain as far as we know (even the genome is very poorly modelled as such). When I said "we've no idea" about the 2060s-70s, I was not being literal. I meant the range of possibilities is extremely wide, and probabilities cannot be usefully estimated. Kurzweil was certainly not being flip in talking about uploading in the late 2030s - it's in his magnum opus, and he says and writes similar things frequently. I've still to see anything you've said that undermines PZ's critique in any significant way.
Posted by: Stephen Wells
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August 24, 2010 3:26 PM
KG, greylander has been very resistant to the concept of there being any info in the cell that's not in the genome; maybe a misunderstanding of evolution is the problem. Cells predate genomes, so genomes have never had to code for cells, only for bits of cells. The genome of a fish does not specify the properties of water :)
Posted by: David Marjanović
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August 24, 2010 4:32 PM
I agree that molecular encoding is a highly unparsimonious hypothesis that isn't needed to explain anything we know.
I can't imagine how that could be possible. You'll have to actually simulate the solvent. And every additional atom will increase calculation time exponentially, even under heuristic methods.
"Photographic memory" means to remember everything one sees, not merely everything one looks at. It further means to remember not just the text of a book, but what each page actually looks like, with all colors, all letter sizes and shapes, all dog-ears, all the stuff that computers either don't bother with at all or store once for the entire book.
Furthermore, learning a book by heart isn't the same as photographic memory. Everyone who's capable of learning a short poem by heart is capable of learning an entire book by heart, provided they have nothing better to do. Photographic memory is something a few people have and everyone else just doesn't.
(OK, photographic memory isn't an either-or condition. I know a guy who can tell you where on which page of which book he read something, and says he sees the page in front of his mental eye – but he can't read it with his mental eye. The resolution is too low. But that doesn't change the fact that photographic memory isn't something you can simply train.)
Why?
Worse. For instance, in vertebrates, things from the plane of the first cell division to the location of the blastopore are determined by the place on the egg where the sperm happens to enter.
Posted by: KG
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August 24, 2010 4:33 PM
Greylander,
Just briefly, because I think we're nearing the end of useful dialogue:
If you want to talk of "rules" for how the genome is read (which is misleading), they are distributed, between the genome itself, the structure and chemical composition of the cell(s), the mother's body, and the external environment.
If computational theory does not distinguish software from hardware, then that's a limitation of computational theory, as far as application to the real world is concerned. I'm quite familiar with different layers of software, and with software that constitutes instructions for building hardware, but software is usefully conceptualised as strings drawn from finite alphabets, which hardware in general is not, and which as far as we know, nothing in the brain is, with the partial exception of the genome (even there, it's only a very crude approximation, as the physical conformation of the genome and its associated proteins and sugars makes a great difference).
Your point about natural selection is irrelevant to the length of a program to specify a brain, as the genome is evolved to make use of vast quantities of external information, without which it will do nothing, and which you will not have in building a simulation.
Differential equations do not deal well with systems that include complex, changing structures such as the cell's membranes and organelles, which act as catalytic sites and reconfigurable filters.
There's nothing at all to indicate that Kurzweil did not mean every word he said in my quote; it's in his magnum opus, and he says similar things frequently. I've seen nothing in what you or anyone else has written that undermines PZ's critique in any important way.
You think its obvious technical change has speeded up in the last century, I think it is far from obvious.
In saying we have no idea what 2060-70 will look like, I was not being literal: I meant that there is a very wide range of possibilities, and assigning meaningful probabilities to them is extremely difficult. If it can be done, the place to start is with things we will find very difficult to halt - like the increase in greenhouse gas concentrations in the atmosphere and depletion of resources - not with speculations about radical technological advances.
Posted by: KG
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August 24, 2010 4:36 PM
BTW, it's odd to say that my examples of undue techno-optimism are irrelevant (OK, strictly, as you say, they "prove nothing"), because they are in exactly the area of dispute - trying to produce machine intelligence through isolating a supposed set of "basic principles".
Posted by: Greylander
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August 24, 2010 9:58 PM
@ #331 CJO:
I was specifically answering the incorrect assertion by someone else that you can't simulate continuous variable systems using discrete state systems.
Your notion of "resist simulation" is flawed. Chaotic systems can readily be simulated. The difficulting in making other than statistical predictions with them is precise because of what you point out "sensitive dependence on initial conditions". In other words the exact time-evolution of the chaotic system can be drastically different over a short interval given the slightest change in initial conditions. It also means that the system is (both real and in simulated) can be highly sensitive to any slight "noise". In real world this can be "butterfly wings" and there are butterflies all over the place. In the system this can include numerical error.
However this only affects the predictive accuracy of the simulation. To illustrate why this is different from saying that the simulation is simply "inaccurate" consider the following thought experiement. Suppose you have virtually unlimited, god-like resources, (but you are not omnipotent or omnicient). You wish to predict the weather on the earth. So, you construct an "exact model" of the earth... a whole duplicate solar system even, so that you can account for solar wind, solar flares, etc. In the blink of an eye, you can "reset" your system to exactly match conditions on the earth. Let us suppose that you can make your duplicate an "exact match" so close that the only differences are at the microscopic scale -- ever-so-slight differences in the positions of atoms. Finally, your simulation runs in some sort of parallel universe where time runs a million times faster than on earth. Now no one could call your simulation "unrealistic". It is as accurate a *model* of weather (and everything else) on Earth as you could wish. BUT because it is a chaotic system, your model will over a few days in its own universe (a few seconds in ours) diverge completely from what will actually happen on eath of the corresponding few days. All you can do is "reset" your model, run it again, do this a number of times, then make statistical predictions about the Earth's weather.
The model in the above thought experiment is as realistic as you could dream of. It is is also perfectly accurate, given it's initial conditions. Yet still it gives inaccurate predictions and can only give statistical predictions if run through many trials. Our computer weather simulations of course have nowhere near the detailed realism of this fantasy model, but they possess the same kind of realism (if not the degree). The "inaccuracy" also going to be the same kind of predictive inaccuracy as the fantasy all-but-perfect model. If you run a whole-world weather model for years and years of simulated time, the weather continues to look like "normal" weather, it just rains on Sunday instead of wednesday in the real world, The first snow in New York in 2014 occurs on November 13th in the sim instead of December 5th in the.
Neural processes are almost certainly also chaotic much like the weather. This would make using a simulation to predict human thought, or to be a "perfect duplicate" personality of a real person ridiculous on the face of it. It is feasible that we one day be able to duplicate you such that your duplicate believes it is you initially. But even if we could somehow feed your brain-doppleganger an exact copy of your own sensory experience, it would rapidly diverge from your thought processes, still believing it was you... but it would be confused: it's sensory input would be based on the results of your decisions and the signals you send to your own muscles... so quickly your brain-dobbpleganger would realize it had no control over its own body, and then it's thoughts would be radically different from your own!
I brain-doppleganger would not be a realistic goal for a brain simulation. But if you just let the simulation do its thing, with "inputs" from it's own eyes and other senses and output controlling its own body (it does not matter whether it has a simulated environment and body or a robot-body) there is no reason why it will not learn and adapt just like the brain of a real person would if it was in the same body with the same sensory inputs.
To sum up. I agree -- if we could feed the simulation even perfect "intial conditions" and sensory input matching a human, then predicting what the real person will say a few minutes after the start of the simulation would be very much using the simulation to predict the course of a hurricane a month in advance. But I do nto think this makes such a simulation "bad", "useless", or "unrealistic". I would still be inclined to call the simulation "accurate" so long as we understand we're not talking about predictive accuracy due to the inherent chaotic nature of the system. I call weather simulations "accurate" in the same sense. Maybe we need a new word to describe the kind of "accuracy" I am talking about. I think "realistic" does more to capture my meaning, but people here have also objected to that word for much the same reason as you object to "accurate". On the other hand, when talking about simulating a chaotic system, my inclination is to think it is obvious that we cannot have "predictive accuracy" so the meaning of "accurate" defaults to the sense in which I have used it.
Posted by: Greylander
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August 24, 2010 10:48 PM
@ #332 KG:
Greylander,
I agree. The horse's corpse has been beaten beyond all recognition.1
I think this is like saying like the rules for what my little "print the sum of each new number and the first number entered" program does are distribute through the program itself but also in the person sitting at the computer entering the numbers -- actually the rules are spread out over all the people who might possibly run the program and enter numbers -- actually the rules are spread out over the whole world, because lightning could strike and kill the person there by preventing them from entering numbers, or they might get distracted by a phone call and subsequently enter a different sequence of numbers than they otherwise would have. After all, there is no way to know what sequence of numbers the program will print out until you know what numbers the user enters. I know you will disagree because you will not see my analogy as valid because the genome, cell, organism, brain, "are not software". I think you don't get it. You think I don't get it.
I completely agree after "because...", but I find the point entirely relevant. It's a mystery to me how we can come to such radically different conclusions.
You still mean simulation of the brain, I hope. Such a simulation *would* be provided environmental input most likely through artificial senses (i.e. convert digital video into simulated firing of rod & cone cells). There is still the matter of initial conditions, but if our model (i.e. "rules") of the brains self-modifying behavior are good, then even somewhat random intial conditions may be all we need -- then let the sim run and interact with its environment and simulated synapse will grow or prune, it may learn and start to think. With the best of whatever brain scanning we can manage and some trial and error getting the initial conditions right, I see no reason why we cannot in effect have a a starting point roughly like that of an infant amnesiac. The first simulations will no doubt be very developmentally disabled.
I think you underestimate what can be done with PDE's, but I do not presume that PDE's are the only kind of time-evolution equations that would be used. All the equations, including a discretized version of PDE would be some form of "change in state" equals some_function_of("current state").It's simply bizarre to say that the software/hardware distinction is irrelevant: the former, but not the latter, consists of strings of digital information - and there isn't any of that in the brain as far as we know (even the genome is very poorly modelled as such).
There is nothing inherently limiting about numerical (digital) approximation to continuous values. I don't get why you (and others) keep bringing up variations of this objection. As to the genome, evidence strongly suggest that the discrete sequence from a 4-symbol alphabet is what matters in terms of how it influences cellular processes, included how it influences subsequent changes in epigenetic factors.
When I said "we've no idea" about the 2060s-70s, I was not being literal. I meant the range of possibilities is extremely wide, and probabilities cannot be usefully estimated.
I've given error bars on my own predictions that are quite large. I'll be (if I'm still alive) quite satisfied if my estimates of "when" are within a factor of three, assuming there are no major global catastrophes and socio-economic upheavals. The bets are off in the event of global mayhem. But my timetable resumes once society restabilizes in a form that permits reasonably unfettered research and development. Let's hope the neo-Catholic Inquisition does not take over... or worse, egads.. the Sharia Inquisition.
PZ was wrong in his initial interpretation of the whole point of the information-in-genome argument (i.e. reverse engineer by looking at genome). You and I simply disagree on "information content". PZ used an extremely bad analogy calling the "ontology" the program which is ridiculous on the face of it.I think my point by point answers here summarize our disagreement. Answering my answers will definitely just mean we're going in circles -- unless something I just said makes you go "Oh... now I get it." Somehow I don't think you are going to say that. :)
Posted by: Greylander
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August 24, 2010 11:22 PM
@ #336 KG:
Mainly because others' examples of undue techno-pessimism (I don't think I've used any... maybe I mentioned one i a supporting point somewhere) get thoroughly slammed here.
That your examples are AI specific does not make them less specious, because if the complexity of the cognitive processing of the brain is as I have estimated, then all attempts to simulate to achieve AI whether by invention or simulation, were doomed to fail until computing power reaches levels we can't expect until the circa 2030 anyway.
Even back in the 80's when I first started thinking about this, based on what I knew and thought about the brain at the time, if I had actually bothered to come up with a number, I would even then have been thinking in terms of near-petabytes and near-petaflops as an absolute minimum. If i had been thinking about the implications of Moore's Law back then, I might have true AI just plain won't be possible until circa 2010 at the earliest. I wasn't putting numbers on it back then, but I did at the time think that computers were ridiculously underpowered to accomplish anything more than "toy" AI models regardless of the particular approach used (symbolic reasoning, "neural networks", and so on). Even toy AI models did some impressive things. Although it used to be thought that Chess was a good kind of AI "test case"... it turns out to be more of a "toy". It is nonetheless extremely impressive that a computer beat a chess master as early as 1997.
Dropping the business of brain-simulations, and just talking strong AI, here is something I would bet on: in the 2030's we will have a lot of controversy about whether some artificial systems had passed the Turing test. The controversy will be due to the subjectiveness of the test and literal interpretations of the rules. It will be difficult for the AI's to pretend to be human, as they will not have had anything like normal human experience. Automated phone-answering systems of that time period will be able to have reasonably natural-seeming conversations with you, unlike the bizarre clunky systems of today. Just earlier today I was somewhat surprised by a voice recognition system of an automated customer service system -- it was able to get my name and address. It was clear from the way it repeated them back that it had translated my spoken words to text, and then it spoke the text back to me using a Stephen Hawking-like text-to-voice system. And some people on this thread don't think computers have gotten radically smarter just in the last few years.
Posted by: Stephen Wells
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August 25, 2010 3:20 AM
Greylander, your disagreement with KG and myself about rules seems to imply that you think the genome provides rules of the "do this, then this, then this" type and that following those rules gets you an organism.
It doesn't.
If you think of the genome as rules, they are all conditionals; each transcribed region says "if you transcribe me you get this RNA", each coding region says "if you transcribe and translate me you get this protein".
Now, if the genome is being transcribed in the context of a viable cell, all those activities will go to maintain the cell, and in the context of embryonic development they'll go towards building the embryo. If on the other hand a cell splits open and the nucleus and ribosomes and all get spilled out, they do not reassemble a new cell, they just die. The genome doesn't have the instructions for building a new cell from scratch, because for all the billions of years genomes have existed they've only ever operated inside cells.
It's a collection of subroutines with no main().
So this supposed information-theoretic limit on the complexity of the brain fails because it looks only at the information in the genome, not in the whole cell, and the cell contains information (such as that it is a cell) which is not encoded in the genome.
No eukaryote has ever reproduced by passing on only its genome to its offspring; it's always been a cell with a genome.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawku8Fdhltvvaj8PR1_AP247K9q5xGzmViI
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August 25, 2010 6:37 AM
Nothing to see here.
OK first PZ mis-characterizes Kurzweil's whole arguments, basically puts words in his mouth, and makes unnecessary personal attacks.
Now he says he writes about Kurzweil's "vague mantra of exponential growth. Why not say 5 years? Why not 50?"
OK PZ, now you are not the one who is well-informed. Kurzweil's future predictions are not just vague guesses. To say that indicates you really no nothing about the man's work.
You need to calm down and grow up a little. You've made an ass of yourself.
Posted by: KG
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August 25, 2010 6:48 AM
Nope, googlemess@341, it's you who have made an ass of yourself, by quite obviously failing to read any of the thread, where Kurzweil's idiocies have been dissected.
Posted by: klewismax
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August 25, 2010 11:37 PM
I've had the good fortune of knowing someone who has had a long-term business relationship with Ray Kurzweil. He has pointed out to me that people who have done business with Ray don't have much confidence in his ability to accurately predict the future. As Steve Novella discussed on a recent Skeptics Guide podcast, what the true test of Crank or Not Crank for Kurzweil will be, is wether he sticks to his fringe futurist guns, or actually works with the scientific community to reconcile his fantasies with reality.
Posted by: Greylander
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August 25, 2010 11:38 PM
@ #340 Stephen Wells:
What I have written suggests no such thing. I may wright long posts, but all the verbiage is mainly in anticipation of just this kind of simplistic misunderstanding and to explain why, in spite of agreeing with (most of) what you say about how cells/genome work, there is still good reason to think that the information theoretic argument holds true. I have to conclude that you have not read my posts, or somehow you selectively ignore much of what you read to make a sweeping assertion about what I believe about what "the genome provides", even though I have quite clearly stated the opposite.
I'm not sure how to respond to this. I think in a way it is trivially true, but a rather odd way of describing things. This is a bit like saying that each line of a computer program means "if you execute me, [whatever] will happen". So something like X=Y+Z means "if you execute this line, the the value of Y+Z will be stored in X" instead of just meaning "store the value of Y+Z in X". But anyway, I do not disagree with your above paragraph, but I will point out that such a tortured notion of "conditional" can just end up leading to a bait-and-switch later in your own thinking, or in an argument, where you then begin to use the word in a more conventional manner, thoroughly muddying the water.
Those on your side of the argument are fond of saying things like "the genome is not executed like a program", but something just occurred to me. If you look at what *physically* happens inside a computer, at the actual shuffling of bits and so forth, then the execution of a program does not look much like the execution of a program either. This is actually a matter of a subjective interpretation as to what "execution of a program" even means, but my point is it is all just some kind of physical process. One can get too caught up in the "program" metaphor on either side of this debate. You can also take it either too literally or not literally enough.
Where to start? So you know for a fact that free-floating DNA never existed? But if it did not, then so what? I have addressed the "information content of the surrounding cell" in several different posts. Again, I think you have not read my posts or simply ignored my arguments. Try looking at my argument for why I do not think there is appreciable *additional* information in the cell, and poke a whole in that, rather than telling me that I have not addressed this when I quite obviously have addressed it. Again. Read previous posts. You know where I described execution of the "program" of that genome as massively parallel, multi-threaded, quasi-random, and non-deterministic. I don't know your background, but those terms are computerese for the concept you are trying to express. Look, I have covered all this and more. There are 4 possible sources of information for the developed organism: (1) genome (2) surrounding cell (fertilized egg) (3) environment (4) laws of physicsAll *prior* sources of information are encapsulate in (1) and (2), while (3) provide all new information. The laws of physics (4) are ubiquitous, and there is very little information in the laws of physics, per se. I have dealt with all of these. You may not agree with the arguments I have made, but don't tell me I have simply ignored "the surrounding cell" or "the environment".
There has been a 5th proposed source: ontology, the development of the organism. It is a process whereby information from the environment, the genome, and the original egg cell, are incorporated moment by moment into the structure of the organism. But in and of itself "development" is not a source of information, it is the process by which the actual sources of information are incorporated. So the proposed 5th source "ontology" is bogus.
No computer program runs without hardware (a cpu), but this does not mean that any information from the hardware is necessarily incorporated into the output of the program. I have covered this already as well.Posted by: Stephen Wells
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August 26, 2010 2:12 PM
Greylander, I realise we'll never convince each other of anything, but please consider:
(i) you claim there's no appreciable information in the cell apart from the genome. What's transcribed from the genome is a function of the state of the cell. The state of the cell thus always depends on the genome, the environment, and the earlier state of the cell, and this chain gos all the way back to before DNA genomes existed. Ergo in order to know what you get from a genome you need at a minimum a complete description of the state of a functional cell, e.g. a fertilised egg, and an environment it can develop in. I find your claim that this is not an appreciable amount of extra information absolutely laughable. FOr heaven's sake, a cell can produce around 100,000 different proteins, and whether or not a gene is transcribed or not could depend on the expression level of any of those proteins (you do know about stuff like repressors and feedback loops in gene expression, yes?). Even if you reduce expression to a yes/no question that would still give 2^100000 cell states. You don't know which one you want.
(ii) do not patronise me about computerese, as if you knew more about it than I do. Trust me, those terms you quote are not at all the point I was making.
(iii) your claim that the laws of physics contain little information seems bizarre to me. In any case, to infer information computationally from a cell+genome, you don't need the laws of physics, you need a good simulation of the laws of physics. That is trickier.
Posted by: Stephen Wells
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August 26, 2010 2:35 PM
A quick reductio:
Everything that happens in the universe obeys the laws of nature.
The laws of nature contain little information (Greylander, 2010).
Therefore everything in the universe contains little information.
Therefore simulating the brain, a supernova, or the entire evolution of life on earth, is trivial.
Posted by: jasonnyberg
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August 26, 2010 5:26 PM
SW, you forgot the "ad absurdum"...
So simple rules cannot give rise to complex behavior?
Just FYI, "the rules a system follows" is not the same as "the state the system happens to be in."
As for accusing Greylander of claiming "there's no appreciable information in the cell apart from the genome": Here's what I think he actually means:
The cell/environment is comparatively boilerplate to the genome as far as development goes, as long as its state is within certain tolerances. That's not to say that its not complex, it certainly is. BUT: It can be perturbed to a much greater extent than the salient persistent digital information in the genome, and still bounce back into a properly developing organism.
You can pluck the nucleus right out of one cell and plop it into another, and the new cell can start chugging along, and can even develop into an entire (cloned) animal, even if the original nucleus is from an already-differentiated cell.
Witness the banging around a zygote may undergo during fertility treatment, etc. where an 8-cell embryo can be literally torn in half and still result in two viable embryos which could develop into identical twins in different ends of the same uterus.
FWIW, the genome itself is literally torn in half too, during the production of sex cells, and digitally merged at conception... But the important parts better come out just right or there will be big trouble down the road...
It's the aggregation of mutations, as recorded in the genome, that has led to our particular body plan including the architecture of our brains. Isn't that the exact idea PZ promotes so convincingly on this blog? Is there another medium upon which evolution's adaptations are recorded, that is anywhere as significant as the genome?
Simply put, the brain is a product of evolution, and the genome is by far the most significant medium in which evolution's adaptations are recorded.
Regardless, we will have solved the brain's information-processing mysteries analytically and via observation of actual brains far before we are able to perform atomic-level simulation of 1 second worth of development of any significant organism.
Posted by: Greylander
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August 26, 2010 8:49 PM
#345 Stephen Wells,
quite possible, but I don't mind if you don't. That is not at all what I claim. There is for all practical purposes infinite information everywhere, and from a philosophical "no way we can really be absolutely certain of anything" perspective, we cannot know for certain what information is relevant to what processes.
In a cell, there is lots of information in the *exact* details of the position of every atom. But that is overwhelmingly the result of thermal jitter and essentially random -- there is no usable information in those details. At larger scale -- molecular and structural, there is still plenty of information. I contend however that most of that information is identical to what is in the genome. By "identical" I mean in the same sense that if you compress the same movie with two different compression algorithm and get to completely different random looking sequences of bits, both compressed files and the original movie file still contain the same "information" even though they each have completely different "data". The portion of information in the cell which is usable and not already captured in the genome is "state" information. And yes, that state information, including things like epigenetic factors is part of what determines the subsequent behavior of the cell, including further modifications to epigenetic factors and which coding portions of genome get transcribed to become proteins, and so forth.
For relative brevity, I'm not going to elaborate on my argument as to why we can neglect the state information as pertaining to the "fundamental structures and processes of the organism."
Of course. This goes without saying. It does not in and of itself change the information theoretic argument. I made no such claim. There is a difference between *contributing* an appreciable amount of information verses whether the amount of informatioin available is itself appreciable.Look, I've allowed about 10^18 bytes just to encode what the brain learns from the environment -- how is that not "appreciable"?
Of course. How does this change anything I've said? I ask that rhetorically. At this point explaining why it probably is not relevant will have us going in circles. I have already covered this. Which one I want for what purpose? Why do I need to know "which one I want?" You need to relate what you are saying to the information content of the fundamental structures and processes of the organism. I have no idea what you do or do not know and had no intent to be patronizing. As far as I can tell those terms quite nicely encapsilate the point you were making about the messiness of how the 'code' of the genome is processed by the cellular machinery. And you accused me of not understanding or taking it into account. But I have taken it into account earlier in this (or previous Kurzweil) thread using those terms, so I wanted to make clear that those terms mean what I thought you meant.Quite often, I am sure, at this point, each of our intended meanings something quite different from the perceived meaning. We've probably exhausted the present mediums capacity for useful communication.
I am aware that it may sound bizarre. But the fundamental laws of physics of which we are aware are encapsulated in a number of equations that can be written down on a few pages of text, which could be encoded with a few kilobyte of binary data. As one of my physics professors (a theoretical (particle) physicist, mind you) once said (paraphrased): "There is not much information in the equations. All the really interesting information is in the boundary conditions." For out purposes here, "boundary conditions" would refer to the detailed state of the cell and environment at a given moment -- the "initial conditions" if you will. Never claimed I was going to do this. This is not necessary for any of my theses.Posted by: Greylander
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August 26, 2010 9:07 PM
#346 Stephen Wells
Everything that happens in the universe obeys the laws of nature.
The laws of nature contain little information (Greylander, 2010).
Therefore everything in the universe contains little information.
This is absurd "reasoning". Your third line does not even remotely follow from the first two. When did I ever say that the laws of physics are the *only* information in the universe? That is just stupid. There is, so far as we know, an infinite amount of state-information required to describe the state of the universe at any given time. To illustrate a little more thoroughly, consider just a system of particles interacting only gravitationally, and to simplify, lets just use Newton version of gravity. You can write down the necessary differential equation in one line. But you can have a system of any number, N, of particles, and each particle must be describe by 3 coordinates and a 3 component momentum vector. That gives you 6N numbers. Those are real numbers, so in a technical sense just one of them requires "infinite" information. But as a practical matter there is only a given precision beyond which any measurement is swamped by random thermal noise, so you will have a few hundred bits of information per "real number". At any rate, if you system has just a few hundred particles, then it can easily contain millions of bits of information. Your differential equation that describes how the system behaves will only take a few dozens of bits to encode.
Therefore simulating the brain, a supernova, or the entire evolution of life on earth, is trivial.
Right. Whatever. Like I have claimed that simuating any of these would be "trivial".
Posted by: Stephen Wells
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August 27, 2010 6:03 AM
I'll just reiterate that no eukaryote has ever reproduced by passing on only its genome. It's always involved a cell, in a particular state, and a genome. A genome on its own doesn't contain the information to produce a cell, let alone an organism, let alone a brain, ergo there's critical information in the cell state that's not in the genome, and doing information theory about the complexity of the brain when your input is the complexity of the genome puts you on a hiding to nothing because you're putting the wrong number in at the beginning.
I think we're done here. Reality can sort out who's right :)
Posted by: tyrannogenius
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August 28, 2010 11:34 AM
Well, we're not really done here! And the comment "reality" can sort it out, gets to the essence of the problem. Yes, given mathematical representation as fundamental to understanding and cognition, then what is reality?
This comes a bit late but gets to the essence of whether we are just "gadgets" - ie, whether we are just "computational intelligences" the minds of which are totally explicable in AI terms of processing bits like computer programs. Jaron Lanier has inspired a certain appreciation against that view, that I develop into the following point:
A purely computational intelligence (as some like Dan Dennett suppose even we are) cannot formulate the thought of special real existence apart from logical structures (ie, such a mind cannot even represent disbelief or an alternative to modal realism/MUH.) That's becasue computations are just math, they can't represent "this is just math" versus "this is my thinking here in a real material world." Well, I don't think CI/AI is true - we are not gadgets! - but that would be the implication.
And since we feel we can imagine this is "really here" and not just a Platonic number space (and similar to the Penrose arguments about our understanding certain concepts), then we aren't "gadgets." Some folks of course think that our universe really isn't more real than math after all (MUH etc.) but if our minds are CI, we can't even think of the alternative regardless.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawnFoajdqDIAo9z1Lwb6KZx0TZowUrx8bXM
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August 28, 2010 3:36 PM
klewismax #343:
No. The thing that many people here seem to be missing is that Kurzweil is not doing science or even making exact prediction. What he is doing is basically "predictive history" or however you want to call it. His basic assumption is very simple: Artificial information processing is getting exponentially faster, the brain is information procession thus we will have artificial brains in the near future (insert technobabble calculating complexity of the brain and looks back at speed increase in the past).
None of his singularity talk makes any hard testable claims, it is simply a prediction that might or might not come true. In 50 or 100 years you can look back and check how far off his general prediction was, but right now you simply don't have the data.
In so far I consider it rather ridiculous to try to debunk him by attacking this or that tiny little detail of his talk, as none of that so far has any relevance to the overall picture. Can't simulate the brain by starting from the genome? Do it by neurons. Doesn't work. Do more observations. Try again with something else. etc. He doesn't claim to know the one true route to understanding the brain, he is simply saying that improved computing power will give people the tools to observe and simulate the brain in more detail.
If you want to attack him, attack the core of his theory that information processing is speeding up and that that in turn increasing development speed. If that doesn't hold up, his predictions falls apart, on the other side if it holds on, then it is not a question of "if", but simply a question of "when" we will have artificial brains, as almost any complexity can be overcome by exponential growth.
PZ Meyers debunking of Kurzweil to me just sounds to much like somebody trying to say human flight is impossible by looking at birds. He might be right in theory, but a 747 flies quite well without flapping its wings. Just because there is lots of complexity from going to genome to brain, doesn't mean that there aren't a hell of a lot of shortcuts, possible optimizations or even completly different routes creating AI.
Posted by: John Morales
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August 28, 2010 9:34 PM
Googlemess id=AItOawnFoajdqDIAo9z1Lwb6KZx0TZowUrx8bXM:
The claim that increased computational power is sufficient rather than necessary to produce artificial brains is speculative and implausible.
If it were merely a matter of that, there'd already be an AI@home project.
Posted by: https://www.google.com/accounts/o8/id?id=AItOawnFoajdqDIAo9z1Lwb6KZx0TZowUrx8bXM
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August 29, 2010 5:46 AM
Yes, but again, thats not actually what his claim is (should have been a bit more precise). He doesn't claim that AI will just magically happen when we have enough computing power, but that that computing power will accelerate research and brain simulation, which in turn will make it possible to create AI.
Or to put it another way: Kurzweil is not claiming that he understands the brain, quite the opposite, he knows that he doesn't understand it, but he thinks that within ~20 years exponential computing power growth will help us to research and recreate it. Unless there is some not-yet-discovered insurmountable brick-wall that we can't get past, I don't see anything wrong with that claim.
Posted by: John Morales
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August 30, 2010 6:09 AM
id=AItOawnFoajdqDIAo9z1Lwb6KZx0TZowUrx8bXM:
So, C → B → A?
Still a direct causal linkage.
And he's setting dates. HAL 9000 in 2030?
Posted by: Mr Spinoza
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September 6, 2010 6:57 AM
I thought we had already back engineered the brain and called it a transmitter, silly me.
Some defectors from the ranks of scientific dogma are accepting it and helping to
make sense of it. It has been given a label now, so we can discuss it. They call it
Cellular Memory. Simply, it’s the idea that the brain doesn’t contain memories. The
brain is likened to the transistor in a radio. Music doesn’t come from the radio, it
comes through the radio. Thought doesn’t come from the brain, it comes through the
brain. In the expanded model, near-term memory and current life thinkings are stored
in the cell of the physical plant. What some think and we all should hope is that this
electro-chemical transistor we call a brain can not only send and receive data
throughout the body, but also pull in the signals that radiate outside this limited realm
of self. It could be said that there is an extent to which we, in any moment, have
“tuned in” to what is beyond us. To the extent that we develop those skills of the
receiver, our levels of connectedness and feelings of purpose will occur.
Stephen C. Parkhill
Posted by: John Morales
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September 6, 2010 7:06 AM
Mr Spino: That you're unaware that "scientific dogma" is an oxymoron explains why you think what you posted has any plausibility.
Congratulations on making up an entire supernatural realm to 'explain' consciousness, quite contrary to the principle of parsimony.
Posted by: Mark Bahner
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December 16, 2010 8:38 PM
Myers: "His first point is silly."
Kurzweil: "For starters, I said that we would be able to reverse-engineer the brain sufficiently to understand its basic principles of operation within two decades, not one decade, as Myers reports."
Myers: "I don't care."
So, you don't care about the facts, or misrepresenting what someone said. Interesting start to a post.
"I suggest that we need to have a combined strategy of digging into the brain from the perspectives of physiology, molecular biology, genetics, and development, and in all of those fields I see a long hard slog ahead."
"...I see a long hard slog ahead" is not a scientific prediction.
Ray Kurzweil has stated that within two decades it will be possible to reverse-engineer the human brain. What is YOUR prediction? That it will never be done? That it won't be done in this century? That it won't be done before 2050?
What is your prediction? Or can't you do any better than "...I see a long hard slog ahead"? (Which is not at all in conflict with Ray Kurzweil's prediction of reverse-engineering the human brain by 2030.)