Built on Facts

Experimental Consciousness

Last Saturday I penned a snarky comment about the philosophy of science, and within a week I read something that’s particularly interesting from that very perspective. Well, might as well use it when it has its uses. Some preliminary:

It is certainly either true or false that Julius Caesar’s paternal grandfather sneezed on his tenth birthday. Can we figure out which using science? Let’s review what has to be available in order to do science. While there’s always debate at the margins as to what constitutes science, virtually any working scientist will tell you that the main issue is being able to test your hypothesis by observation. Sometimes this is cast specifically as as falsifiablilty; but we have no need to be so picky. Can we test whether the sneeze happened? No, unless science invents a time machine. The sneeze either happened or it didn’t, but we’re in the dark about it and will remain so.

PZ Myers, as is his wont, recently wrote here that after his death he will have ceased to be. In other words, his experience of consciousness will have ended forever. Can we test this?

He could die and then make the observation as to whether or not he still existed. If he still did he’d be surprised, but at least he’d be able to observe that he was still somehow existing. If he didn’t still exist, he’s not around to make the observation of his nonexistence. So personal experimentation can’t verify his prediction. Neither can anyone else’s, for the same reasons. A dead person can’t observe his nonexistence, and a dead person couldn’t communicate their continued existence either on account of being dead.

We live in the world of modern science however, and we have snazzier methods than that. How about the neural correlates of consciousness? An awake person has different brain activity than a sleeping person. Modern neuroscience can in some cases be quite fine-grained about the connection between mental states and neural activity – famously one guy had a single neuron which fired when he thought about the Simpsons. Neural activity is clearly kaput upon death, so is that adequate to say consciousness does not survive death? Could be, a lot of scientists think so.

It’s still not testable though, strictly speaking. Simulate a brain on a computer. Is it conscious? How about if you simulate it on an abacus? How about if you have a huge printed “choose your own adventure” book of neural states, it is conscious? Beats me. But they are exactly analogous to the real squishy brain in terms of their states and processing, and we totally lack a way of saying whether they have conscious experience or not, regardless of how finely we can experimentally examine them. There’s just no way to make that link between computation and qualia. For that matter, there’s controversy on whether conscious experience even exists as anything more than an illusion of brain processes. Daniel Dennett doesn’t think so. I tend to think that hypothesis is self-defeating, but then I have precisely no experimental test for that supposition either. And all that is just trying to test whether conscious experience necessarily is generated by a particular class of physical processes. The other direction is worse – imagine trying to experimentally test whether something without those processes is conscious – for instance, the whole universe in some pantheistic religions, or an immaterial soul in the monotheistic and other religions. But on the other hand lack of testability doesn’t mean it’s impossible; the sneeze certainly isn’t.

Where am I going with this? Nowhere, that’s the point. Clean experimental testability is why I like physics.

Comments

  1. #1 kevin
    October 21, 2008

    Can we test whether the sneeze happened? No, unless science invents a time machine
    Oh don’t be silly. This is a hard, but legitimate and well-posed question, and science can, in principal, answer it. How? Got me. Maybe we find some evidence that the grandfather was in a coma on his birthday, hence no sneeze. The information needed to answer the question isn’t forthcoming, and probably won’t be any time soon.

    Your other questions are, for the most part, ill posed and nonsensical. Suppose there is this thing called consciousness. Except it has no physical manifestation whatsoever. So not a thing per se, but more of a concept. And i won’t actually give you a definition of the concept, just a sort of vague description of it, more of a hint of a concept. Now, does the concept apply to dead people? Does it apply to a tree? Or the earth? How about a particular algorithm run by monkeys using abacuses (abucii?)? Does it apply to the number 7? Does it apply to Ohms law? Does it apply to that wink that Sara Palin keeps doing?

    You want to know if these questions are answerable. But you haven’t asked a question, you have just strung some words together and put a question mark at the end.

  2. #2 Tercel
    October 21, 2008

    You are correct, of course, that none of these hypotheses can be directly tested. However, that doesn’t mean we can’t make some valid conclusions, given the caveats that science never claims any sort of absolute truth, and that speculation, extrapolation, and reasonable inference based on what we can observe are better than nothing.

    I’d also point out that science must, a priori, eliminate certain possibilities simply by definition. The concept of a non-physical soul, for example, is one such possibility. This is not to claim that a soul cannot exist, simply that it is not a valid scientific theory. In other words, we must accept that if supernatural phenomenon exist, we cannot explore them with science. I accept this limitation, independent of the fact that I do not personally believe there are supernatural phenomenon. For the same reason, I also wish that some people would quit whining when their beliefs are called unscientific, as if everything good or right had to be science. But I digress…

    With the preceding in mind, we can note the fact (which you spoke about in your post) that we already know quite a bit about the connection between mind and brain. Our experience of consciousness makes us feel like there must be more to it than the physical processes of our brain, and maybe there is, but I can see no scientific reason to assume so much. Putting aside philosophical questions of what it means to be conscious, or whether computer AI have qualia, it seems reasonable at the moment to assume that our mind is fully encoded, contained, and carried out in our physical brains. At the very least, we can assume that our physical brain is a necessity for our consciousness, even if it is not the sole contributor. Thus it is not wholly unscientific nor groundless to conclude (tentatively, as in all of science) that our consciousness utterly ceases when our brain stops functioning.

  3. #3 Tercel
    October 21, 2008

    There is also the fine distinction here between different kinds of un-knowable facts. There is the un-physical, or that which is not in any way “real,” and that which is simply insurmountably difficult to measure.

    For example, a high resolution picture of the photosphere of a star 10 billion light years away, or the exact location of each sand grain in a bucket, are not really measurable (ok maybe somebody clever can think of a way, but bear with me for the example) yet the information is real. Sand grains have real locations (I use sand, not gas atoms, to avoid bickering about quantum mechanics) and stars, no matter how distant, have surfaces with features which are real and do exist.

    In the other category, that which is non-physical or unreal, we could ask what the surface of a proton looks like, or what god is thinking right now. These questions are either undefined, or simply meaningless. A proton doesn’t really have a “surface” in the same way that a tennis ball does. Certainly nothing you could image, regardless of technological sophistication. The thoughts of god are thoroughly unknowable, as he does not appear to be a part of this universe, whether you believe he exists or not. (I’m just using god here as a well known concept that I can talk about without explaining, which refers to something not in the universe. If you believe that god is in the universe, or whatever, that’s fine. I’m just trying to make an example.)

    Other questions are meaningless in their very construction. Does it make sense to ask how many hours are in a kilogram? Of course not, but this sort of meaningless question is a bit of a digression.

    Whether Caesar sneezed is, I would suggest, a member of the first category. The question refers to a real event, which would have been, and may still be, measurable in principle. For example, maybe if we knew every other event since then with enough precision, we could trace the path of air molecules back in time to determine what they were doing in front of Caesars mouth. Maybe we wouldn’t even need a complete history, maybe just a good one. Maybe we could build a huge telescope and capture some light which carries an image of the event, bent around back to us by a pass near a black hole. Regardless, it is certainly impossible to actually do this, but that doesn’t make the question meaningless, or the event non-physical.

  4. #4 Uncle Al
    October 21, 2008

    What is worth knowing in theory or in falsifiable fact given its cost of acquisition? Clear views of Mars are good, local satellite telemetry is good, landers and rovers are good. Is more better? No.

    http://phoenix.lpl.arizona.edu/
    expensive piece of crap

    String theory is an elegant exercise of mathematics as are all quantized gravitation theories plus SUSY. Do they sum to anything empirical, do they make progress? No. Heed and fund rational alternative voices. Do better, innovate, or quit while behind and redirect scarce resources.

    When you get to the bottom of a hole, stop digging.

  5. #5 Fred Nurke
    October 21, 2008

    PZ Myers may claim all he wishes that < > but he is basing his claim on our limited understanding of time as a real dimension. He still continues to exist at the points in time denoted as between birth and death. He doesn’t exist outside those points, but then, he “never” did, any more than he existed outside the other 3 dimensions.

  6. #6 Tercel
    October 21, 2008

    You’re saying the same thing as him just in a different way.

  7. #7 glenstein
    October 21, 2008

    uncle al,

    I think a couple of things are being conflated- there is the “bottom of the hole” in the sense of the limit of what we can know, beyond which knowledge is impossible (either practically or literally); there is also the totally distinct issue of “immediately useful”- there are many ways in which string theory is not immediately useful, but which nonetheless describe a knowable reality. There is more to uncover, more to learn, which is just as real or true as anything else, regardless of whether we can actually use it.

  8. #8 Jason
    October 22, 2008

    I think Kevin’s comment #1 is excellent. The post doesn’t show that claims in physics are somehow “more testable” than claims about consciousness. It just shows that claims in physics are much more rigorously defined. PZ’s comment isn’t untestable – it just requires careful clarification before it can move from being a philosophical claim to a scientific one (which I think is a point that PZ would readily admit).

  9. #9 Russ
    October 22, 2008

    The tone I get from your post suggests that the two sides are equal in weight, and I don’t think that’s the case. There is volumes of evidence showing that effects on the brain correlates to changes to the mind. The resulting brain theory of the mind then makes a logical deduction that the mind ceases when the brain does. The other side has no evidence to support it’s claim aside from ancient tracts and anecdote. Yes, you cannot conclusively prove one over the other, but one of them seems to have a much higher probability of being right.

  10. #10 jayh
    October 22, 2008

    In other words, we must accept that if supernatural phenomenon exist, we cannot explore them with science.

    What is ‘supernatural’? Almost a circular definition, I guess being ‘beyond natural’. But aspects of it should be testable. If humans have been making a transition to an alternate life form at death for thousands of years, how can that be ‘beyond natural’.. indeed if that were the case then it would be totally natural.

    We can measure phenomena, regardless of whether they are thought to be supernatural or not. And if quantifiable evidence appears then the definition of natural changes. On the other hand, if after thousands of years, nothing shows that isn’t more explainable by more prosaic means, science has also weighed in on the negative side of a ‘supernatural’ event, that it can safely be assumed that these phenomena do not exist.

  11. #11 Tony Jeremiah
    October 22, 2008

    I’d have to agree with jayh. Describing an inexplicable phenomenon as supernatural (presumably synonymous with magical) is a tautology. If the phenomenon exists, it is an aspect of the universe and should therefore be considered natural. So I think the primary issue is not the magic-ness of the phenomenon, but rather (again assuming its existence) its inexplicable nature based on current accepted conceptualizations of existence. As examples, one could imagine transporting any current electronic device several hundred years back in time. No doubt persons encountering those devices would consider them supernatural. Likewise, if time travellers from several hundred years in the future came back to our time, we may observe devices that would appear to have supernatural capacities (e.g., imagine seeing a person appearing and disappearing without being aware of the presence of a transporter).

    One currently inexplicable phenomenon is the ability of persons who have had near-death experiences to report events happening around them after resuscitation from clinical death. This would seem to suggest consciousness in the absence of biological activity. This supports the dualistic rather than the (dominant) monistic view of consciousness; possibly suggestive of of a spirit/body dichotomy.

    To explain such a phenomenon, our perception of reality would need to be altered. In relation to physics, I particularly like David Bohm’s idea of a holographic universe. Technically, one could imagine all objects in the universe as being holographic projections.

    Perhaps the “spirit” of living organisms are in fact holographic projections with a machine/body interface that is disconnected at death.

  12. #12 Anonymous
    October 22, 2008

    “Describing an inexplicable phenomenon as supernatural (presumably synonymous with magical) is a tautology. If the phenomenon exists, it is an aspect of the universe and should therefore be considered natural.”

    Yes, that is exactly correct. If something has any manifestation in the physical universe, it is not supernatural. I never claimed that every unexplained phenomenon was supernatural, that was something that other people read in to my post.

    Note that sometimes people can assign a supernatural explanation to a real (or “natural” if that’s the word you like) event. For example, if a man recovers from an illness which was expected to be terminal, some might claim that it happened because god directly intervened, ie. a miracle. This is a supernatural explanation for a real event, and is not scientifically acceptable, regardless of its truth. This does not make the man’s recovery supernatural, it simply means that we do not have an explanation. Unexplained and inexplicable are not the same.

  13. #13 Tercel
    October 22, 2008

    Comment #12 was me, I just forgot to put my name in the box. Oops.

  14. #14 Tony Jeremiah
    October 23, 2008

    I never claimed that every unexplained phenomenon was supernatural, that was something that other people read in to my post.

    However, a hidden tautology remains here, that I think is due to a subtle distinction between phenomenon and explanation which is implicit to this and your remaining comments.

    Verifying the existence of unexplained phenomena in the natural world, by definition, makes all such phenomena, natural. So technically, the statement above can be reworded as, “I never claimed that every unexplained verifiable phenomenon [in the natural world] was supernatural”. This is a claim that actually should be made because technically, it is factual. The tautology results from the assumption, supernatural (phenomenon) = unexplainable/inexplicable phenomenon.

    Note that sometimes people can assign a supernatural explanation to a real (or “natural” if that’s the word you like) event.

    True. And again, I think this is a product of the supernatural = unexplainable/inexplicable phenomenon assumption.

    For example, if a man recovers from an illness which was expected to be terminal, some might claim that it happened because god directly intervened, ie. a miracle. This is a supernatural explanation for a real event, and is not scientifically acceptable, regardless of its truth.

    True. And this example provides a good llustration of the importance of distinguishing between a verifiable phenomenon (recovery from a terminal illness) and a (supernatural) explanation of the phenomenon (god did it). This supernatural explanation is not scientifically acceptable because it does not pass the falsifiability criterion. For this to happen, one would have to (1)operationally define god; and (2) show how god healed this person (which would probably require evidence of a naturalistic mechanism given that the healing takes place in the natural world). Doing any of those things automatically makes god an entity of the natural universe, and therefore, not a supernatural being.

    This does not make the man’s recovery supernatural, it simply means that we do not have an explanation.

    True. And again, I think this is a product of the underlying assumption that a (verifiable) phenomenon that cannot be explained (by current understanding of the natural world) is a supernatural one.

    Unexplained and inexplicable are not the same.

    I would assert that unexplained = inexplicable if it can be shown that supernatural explanations for natural phenomena cannot be falsified.

  15. #15 haig
    October 23, 2008

    The fact that science itself is at all possible presupposes an ordered universe. Nonrandom causal events proceed in a forward direction through time which humans observe and experiment on, which leads to scientific theories, tentative as they may be upon further experimentation.

    All we know and can ever know (know in the rigorous information theoretic sense) is based on a model of an ordered universe. What if there was a process that exhibited itself as a random pattern, truly random like chatin’s omega number. We would never be able to understand such a thing. Our map of the territory is necessarily limited to the knowable.

    That is a problem I’ve always wondered about. What if there was a natural phenomenon that appeared randomly and say you experienced such an event. Maybe some sort of paranormal experience. Yes occam’s razor says you should go to a shrink and/or stop taking so many drugs etc, but for the sake of argument, if such a phenomenon were ‘real’ but exhibited itself randomly how would we know?

  16. #16 T_U_T
    October 23, 2008

    “What if there was a natural phenomenon that appeared randomly and say you experienced such an event.”

    you mean something like radioactive decay ?

  17. #17 windy
    October 23, 2008

    PZ Myers, as is his wont, recently wrote here that after his death he will have ceased to be. In other words, his experience of consciousness will have ended forever. Can we test this?

    The hypothesis is falsifiable, by PZ Myers.

    It’s still not testable though, strictly speaking. Simulate a brain on a computer. Is it conscious? How about if you simulate it on an abacus? How about if you have a huge printed “choose your own adventure” book of neural states, it is conscious? Beats me.

    Once you dismantle the computer and burn the book, do they have the same chance of being conscious as before?

    But they are exactly analogous to the real squishy brain in terms of their states and processing

    Seems like a tall order.

    and we totally lack a way of saying whether they have conscious experience or not, regardless of how finely we can experimentally examine them.

    But wait a minute, if there is no possible way of telling if something is conscious, you have no grounds for assuming that PZ Myers is even currently conscious! So it seems rather silly to ask if his consciousness can survive his death if we have no grounds for assuming he has one. I am guessing that you don’t really believe that, though.

    For that matter, there’s controversy on whether conscious experience even exists as anything more than an illusion of brain processes. Daniel Dennett doesn’t think so.

    This seems like a mischaracterisation of Dennett’s position. He thinks that there is no mysterious indivisible consciousness apart from the “performance of functions” of consciousness.

    Where am I going with this? Nowhere, that’s the point. Clean experimental testability is why I like physics.

    What was the maximum speed relative to the ground achieved by Caesar’s paternal grandfather on his 10th birthday? That physics question doesn’t seem any more testable than the sneeze.

    In contrast, we can ask if Caesar’s paternal grandfather was conscious any time on his 10th birthday. It’s not testable either, but I think we can be somewhat more confident of the answer than about his sneeze or his movement. Don’t you?

  18. #18 haig
    October 23, 2008

    @T_U_T
    Radioactive decay, like also the movement of an individual atom, is random, but in aggregate are statistically predictable. Thermodynamics is a predictable science in spite of the underlying randomness, we’ve just used the tools of statistics to make it more comprehendible, but again only in the case of large sample sizes.

    If a certain phenomena occurred in small sample sizes and again with a random pattern, we would not be able to repeat it experimentally or via purposeful observation. This is the meaning of unscientific, maybe it is ‘real’ but it is not available to scientific inquiry at least as science is practiced so far. I agree that to uphold reason you would only believe in things for which there are proof for and so I am not saying that paranormal events are real, and I don’t believe in any, but I also don’t deny that it is plausible for such things to occur and I may update my beliefs as evidence sees fit.

  19. #19 Renee
    October 29, 2008

    Depends on what the definition of science is.

    No, really. Science is a collection of methods used to find out the truth. Some of these methods are really good at finding out the truth, but can only be used in limited situations. Other methods are less effective, but can be used more broadly. You use the best tools you have.

    The philosophy of science seeks to come up with a logically consistent idea of what “science” is, and any one of them would say that your definition of science is wrong as it is both logically fatally flawed, and excludes too much of what we call science.

    Personally I don’t care what you call science or not, as long as you acknowledge that there are different ways of finding things out and that they should be judged according to how good they are at getting results.

    None of the tools we have will ever give us absolute truth, because experimental science is not axiomatic, so why not use all the tools we have to get as close as we can?

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