Pharyngula

Posted by: Krisko | July 3, 2009 12:06 AM

I love the notion of creation myths being "too provincial." That's a term I have to start using more.

Posted by: Shawn Wilson | July 3, 2009 12:13 AM

I've read most of his books, but this is the first time I've heard him speak. Not at all the voice I heard while reading. On that note, I just heard PZ for the first time a couple days ago. I was shocked that he wasn't curmudgeonly. :)

Posted by: Zeno | July 3, 2009 12:18 AM

I was lucky enough to hear Feynman lecture in person a couple of times. He was wonderfully compelling and extremely effective in explaining things. A brilliant and clear thinker whose contributions significantly advanced the state of the art in physics.

Of course, I don't always agree with him.

Posted by: Abber | July 3, 2009 12:31 AM

Scientists just want to learn more about the world!? They should be at home reading the answers in the "special stories" of the Bible!

Feynman rocks.

Posted by: Kobra | July 3, 2009 12:56 AM

I could not have said it better myself.

Posted by: John | July 3, 2009 1:41 AM

Feynman knows where it's at. Just as an additional note, I think that he acknowledges with the whole "...its no use arguing, I can't argue..", and the rest of the phrasing emphasizing his personal perspective, that while we all know that what he's saying is 'right' and how we are 'supposed' to approach things, he very much means this is his own personal approach.

From my reading of Feynman I have always been impressed not just with his emphasis on the limitations of our knowledge and uncertainty as an inherent part of science, but also his emphasis (or disclaimer) that what he says is just from his personal perspective. He seems to realise that that inherent focus on doubt is a part of him (probably influenced by his father tho' to be fair) and that there are others who, no matter what he does or his frustration, just won't agree with him.

Furthermore, reading his books and the biography by Gleick I was attracted to his positive approach of just putting out how he does things, without saying this is how others should do them also, and perhaps hoping this will be the best way to get people thinking, rather than trying to impose his views on others too forcefully or as universal truths. He had a very compelling honesty with regards to his own views and his own limitations, which made one wonder about one's own without feeling like he was trying to convince you of or sell you anything.
He seemed to really know how to engage with others' perspectives and 'lead' them through his own observations. I suppose that unfortunately this won't work in all cases tho'...

Posted by: Pat | July 3, 2009 1:45 AM

The Feynman interviews are consistently excellent.

One of his quotes from the clip above was one I used for a piece I wrote arguing against Paul Davies:

http://mclir.blogspot.com/2007/11/response-to-paul-davies.html

Posted by: Felix | July 3, 2009 2:17 AM

When you're so far above average in intellect (he must be easily five points above me or so ;) ), it's obviously very difficult to downthink yourself to the level of narrowminded monotheism - which itself thinks it's got the greatest possible Truths at hand. They're globally projected cosmic Dunning-Kruger.

Posted by: Dr. P | July 3, 2009 2:42 AM

The humility and straightforward nature of the man is disarming when you consider the import of what he's saying;I have to read more about him.

Posted by: antistokes | July 3, 2009 2:54 AM

While I loved Feynman's "plenty of room at the bottom" speech, I've disliked the popsci writing of his that I have read-- too many exclamation points for me (I'm more a fan of the David Griffiths style).

Posted by: SmartLX | July 3, 2009 3:07 AM

I like this man. I'm sorry he's gone.

Posted by: CJ | July 3, 2009 3:16 AM

I'd never heard the man speak. I'm suddenly feeling a little moist.

Posted by: Brian's A Wild Downer | July 3, 2009 3:22 AM

It's incredibly weird to hear someone I've never met echoing my exact world view.

Posted by: Paula Kirby | July 3, 2009 3:53 AM

#20 - Steven Carr

Posted by: Steven Carr | July 3, 2009 3:03 AM

Religious types point out that science has all these questions that cannot be answered.

Scientific types point out that religion has all these answers that cannot be questioned.

Sums it up perfectly!

Posted by: Your Mighty Overload | July 3, 2009 4:27 AM

Andyo @ 26

The oxygen from photosynthesis comes from the splitting of water molecules by a chlorophyll molecule (called PSII (photosystem 2)). The PSII basically "wants" a hydrogen atom (proton). The plant sets up a concentration gradient of protons across a membrane (the thylakoid), and uses a special protein (called ATP synthase) to generate chemical energy as the protons cross the membrane through the protein.

The CO2 is fixed by an enzyme called Rubisco (Ribulose-1,5-BISphophate Carboxylase / Oxygenase). Rubisco, as well as being the enzyme I study, is the most abundant protein on the planet. Rubisco converts a 5 carbon compound (RuBP), into two 3-carbon compounds called 3-phosphoglycerate. This is then used to make sugars, and all the wonderful things plants make.

So, to put it this way, Feynman either misunderstands the biology or (more likely) is deliberately simplifying (albeit to the point of being incorrect).

Posted by: Helioprogenus | July 3, 2009 4:56 AM

Eat that Murray Gell-Mann!

This is exactly why you cannot approach Richard Feynman's level of insight and investigation. Your support for incoherent toroid development is so shameful, and outside your own field of investigation, that you can't hold an iota of comparison to Feynman's greatness. This is how a true scientist with an eye for inquisitive wonder of the universe thinks. You come with some pre-conceived notion and it clouds your reasonable judgment and mars your intellectual feats.

Posted by: Rorschach | July 3, 2009 5:25 AM

"Im not frightened by not knowing things"

and

"Its much more interesting to live not knowing then to have answers that are wrong"

What a great guy.

Posted by: Rorschach | July 3, 2009 5:51 AM

Indeed.

Should hit the religious zombies over the head with those quotes, too.

Posted by: Michael Kingsford Gray | July 3, 2009 6:33 AM

A true genius.

Posted by: David Utidjian | July 3, 2009 7:34 AM

Rorsach @33:

This illustrates an aspect of humans and many other animals that the Christian god (or any "omniscient" god) lacks: curiosity. Omniscient gods can't be curious because they already know everything... What a boring existence that must be to already know everything that can be known. No new experiences, no surprises, no joy from figuring something out... boring forever.

-DU-

Posted by: John Morales | July 3, 2009 8:01 AM

YMO @29,30,

So, to put it this way, Feynman either misunderstands the biology or (more likely) is deliberately simplifying (albeit to the point of being incorrect).

Mostly the latter, I suspect. I've take minutes regularly for committees including scientists and regulators, and just now watched the video and jotted some raw* notes:

-- begin notes --
wood comes from a tree.
almost all substance of trees comes from the air, not the ground (a little bit from the ground, minerals and the like).
carbon comes from the air (co2 from air, changed, kicks out oxygen, leaves out the carbon).
water out of the ground, but it got there there from the air (precipitation).
how does the tree split the co2? life!
sunlight knocks oxygen away from the carbon - it takes sunlight to get the plant to work!
on burning, wood goes back to energy and co2.
the light and heat from burning wood is the energy that came from the sun.
it's stored sun[light] that's released on burning a log!
-- end notes --

FWIW, I think you have a point, it does seem to imply the O2 released comes from the CO2 not from H2O; as a layperson, though, I ask: where does the O from the Co2 go after photosynthesis? You don't say (that I can see) in your comments.

--
* I would normally review and massage those notes into something more coherent, fear not. Also, watching the video those exclamation marks were, um, too evident not to note! ;)

Posted by: David Utidjian | July 3, 2009 8:16 AM

Andyo @26:

I'd like to hear biologists' take on this one:

I am not a biologist (I am a physicist). He skipped the whole process of photosynthesis (and probably a lot more I don't know anything about).
He also skipped the fact that much of the material of the plant is oxygen and hydrogen in addition to the carbon. The percent mass of those three elements that make up the plant was also not discussed.

While the physics part of that thumbnail description Feynman gave in the interview is basically "correct" it left out a huge number of facts of physics, chemistry and biology.

I think it would have been a better if he could have at least mentioned photosynthesis, he could have even discussed it for hours, without it detracting from the main point of his description which was that the fire from the burning of wood comes from sunlight.

-DU-

Posted by: Your Mighty Overload | July 3, 2009 8:29 AM

John M at 41;

Apologies. I was fairly sure, but wanted to check anyway - the entire CO2 molecule, oxygens and all, are fixed. The equation for the fixation of CO2 is;
RuBP + CO2 ----> 2X 3-PGA
with the reaction catalyzed by Rubisco.

Posted by: Kel | July 3, 2009 8:38 AM

PS I'm waiting for Feynmaniac to comment here! ;)

Posted by: John Morales | July 3, 2009 8:44 AM

YMO @45, thanks!

Wow, I didn't know Phosphorus was so very crucial to (basically) so much of life on Earth.

And your point earlier is well sustained, though reading up on Feynman it seems he "also had a more-than-casual interest in biology" [Wikipedia]. But yeah.

--
I love that it's named Lucifer, too. Such serendipity! ;)

The first form of phosphorus to be discovered (white phosphorus, discovered in 1669) emits a faint glow upon exposure to oxygen — hence its name given from Greek mythology, Φωσφόρος meaning "light-bearer" (Latin Lucifer), referring to the "Morning Star", the planet Venus.

Posted by: GlenInBrooklyn | July 3, 2009 8:56 AM

By the way, Feynman was the guy who figured out why the Challenger exploded by, after days of hearings, dipping a piece of the O-ring material in a cup of ice water and effortlessly shattering it, on camera:

"Feynman managed to obtain a glass of iced water, and used it to cool a section of O-ring seal clamped flat with a small clamp he had purchased earlier at a hardware store."

Much to the chagrin of the assembled so-called experts, need I say. I watched it in slack-jawed admiration.

Feynman, despite his Nobel prize, was never quite taken as as seriously as his "very serious" fellows. He was a bit of an imp and (horrors!) he played the bongos.

http://en.wikipedia.org/wiki/Richard_Feynman#Challenger_disaster

Posted by: Jack Krebs | July 3, 2009 9:04 AM

I am a Feynman fan, and this video gets to the heart of the matter: I would rather live with uncertainty than believe things that are not true. I learned to put it that way from reading Feynman.

Posted by: Roland Branconnier | July 3, 2009 9:14 AM

Thank you PZ! Listening to the late great Richard Fenyman expounding on a universe with purpose is refreshing on a Friday morning usually reserved for Woo-Woo. Imagine, a universe without teleology, as Carl Simon said: "That's the way I heard it should be." and that is the way it is.

Posted by: Roland Branconnier | July 3, 2009 9:21 AM

Thank you PZ! Listening to the late, great Richard Fenyman expound on a universe without purpose is refreshing on a Friday morning usually reserved for Woo-Woo. Imagine a universe without teleology, as Carly Simon said: "that's the way I heard it should be" and so it is.

Posted by: AJ Milne | July 3, 2009 10:04 AM

Re #52, yes, but this is the nature of the religious psychology. If they find someone they find they must admire has what they consider a 'poor' view of religion, they'll find some justification they imagine puts it back on specific, peculiar circumstances. Bad experiences, so on. It's a nice, pat explanation that avoids their facing the uncomfortable truth that sensible, nice, honest people just don't like religion just because of what it intrinsically is.

I hear the same thing all the time. 'You seem like a smart guy, nice guy, just got a bad attitude about this one thing... Must been a bad experience'.

Funny you should mention that. Because, well, sure it was. But not like you might be thinking, no. The priests I knew were decent folk, as far as it goes, no one molested me, the religious communities I experienced in my youth in weren't especially dysfunctional, so far as I can tell, from comparing them with others. There's one or two of those guys I'd still happily have a beer with if I bumped into 'em...

But these were still religious communities. Which is to say: however many paeans they sang to open mindedness, their thinking was deliberately muddled to protect the old myths around which they coalesced, and it became clear to anyone present who was even half aware of what was going on: you were expected to play along to belong, at the very least in public. There was a certain collateral damage I think I could see that resulted from that, too, around and about--a certain intrinsic two-facedness that comes from telling people: 'Lie. We all do. It's expected, accepted for this particular thing. Keep lying, you might start to believe it well enough.' But my throwing it over the side wasn't primarily about that...

I was just tired of the dishonesty, decided I'd rather risk making enemies of these folk than continue to play along. Decided I wanted to break the cycle, stop repeating the BS. I suspected playing along wouldn't always be so benign... I did see some rather ugly emotional manipulation in certain charismatic movements moving through... But again, it wasn't so much about that. It was personal. Call it aesthetic, if you will... Or even principled:

Mostly, I decided I just didn't like that taste of rank dishonesty in my mouth.

So no, I wasn't worried about any priest's member going somewhere I don't want it. I didn't exactly suffer emotional terror at anyone's hands, either. I just don't want the grubby paws of those petty little lies and half truths around my frontal lobes, thanks. Those are icky, and make me feel dirty.

Me, I'm almost tempted turn it around. You say I must have had a bad experience? Fine. I'd say you must be a coward...

Except that I won't, not quite. I can say only that you might just be a coward. It might also just be: it's complicated for you, like a lot of things are. A large part of the whole game religion plays is to wind itself up in social life, make it complicated for you. You know leaving, calling it the BS we both know it is might cost you, and you think twice. So maybe I don't blame you. I don't know your situation.

Anyway, best of luck with that. Coward or not.

Anyway, re Feynman, damn straight. A good man, greatly missed. And what he said.

Posted by: maddogdelta | July 3, 2009 10:12 AM

Scotth #56

http://is.gd/1mlLG For those who are just now hearing of him, it is a fabulous introduction.

Thank you for that!

Posted by: reggie | July 3, 2009 10:19 AM

This is indeed a "rational view of the Universe" and one shared by a number of physicists, but unfortunately not shared by most biologists.

Posted by: Your Mighty Overload | July 3, 2009 10:41 AM

Reggie at 63;

You'll have to be a little more specific if you want that comment to fly. I'm a biologist, and I think you are talking shit.

Posted by: AJ Milne | July 3, 2009 10:46 AM

Re #65--by way of explanation, I'd expect you'd find most busted con men would readily call the judge that jailed them pretty close-minded too.

Re #64, thanks.

Posted by: Your Mighty Overload | July 3, 2009 11:00 AM

AJ @ 67,

Thanks, figured it was some intellectual coward who can't accept that they got called out on something they were wrong about.

I'm wrong about stuff all the time, but Reggie, here's what I do, I say "oh, right, I got that wrong. Thanks for explaining it". That's called being a man about your failures. Bitching and snide comments is a failure to accept correction, and is, as well as being intellectually dishonest, pretty damn stupid.

Posted by: Feynmaniac | July 3, 2009 11:12 AM

Yeah, where is the slacker ! :-)

I was sleeping!

Honestly, when I chose my pseudonym I didn't think anyone outside a few physics nerd would get it. I had just recently read What Do You Care What Other People Think? and it renewed my love of science in general and physics in particular. The "iac" was obviously added because I'm a maniac!

Feynman had a lot of qualities I admired: intelligence, love for physics, a deep curiosity, skepticism, a good sense of humor, but perhaps the best one was the one that is displayed in this clip: he held truth above certitude. Finding out about how nature works is interesting and stubbornly holding a particular set of beliefs will only hold you back.

Well, that was the best I could do without coffee in my system.

Posted by: apthorp | July 3, 2009 11:31 AM

One of the most refreshing aspects of Feynman is that he just doesn't care about social Truth, including things like proper respect for the proper respect for Physics or Biology. Right and Wrong get replaced by 'does that raise an interesting question about the world' and 'does it inform a question I'm interested in'. Beyond that is the amiable 'I don't know how to argue about that'.

It's possible to over do the clarity angle ... he is entertaining to listen to, and because of lack of interest in setting boundaries and pointing out who is wrong, easy to agree with. An undergrad E&M course using the Feynman Lectures pretty much reduced me to mumbling idiocy*. The beauty and clarity became apparent only later after grasping the question.

*perhaps a natural state, but not the point if this story.

Posted by: naturalist | July 3, 2009 11:37 AM

Scotth@56

Thanks also for the Nova video segments on Feynman. The 1st and 2nd one where his sister recounted how Richard woke her up to go to the golf course to look up and wonder at the aurora was very touching. His questioning fascination with the universe influnced her to become a astrophysicist and you could see the gratitude and love in her eyes for the lasting gift he gave her.

Posted by: Dee | July 3, 2009 11:55 AM

I saw this interview way back when it came out on NOVA/PBS. We have two PBS stations in Salt Lake, and I enjoyed the interview so much I watched it everytime it came on, on both stations. I'll bet I watched it almost a dozen times, and it never got stale. It was a great interview, and Feynman was wonderful. I still think it was the best interview I ever watched. If you can find the whole thing, spend the time.

What a great memory this post brought back - thanks.

Posted by: co | July 3, 2009 12:05 PM

Reggie at 63;

You'll have to be a little more specific if you want that comment to fly. I'm a biologist, and I think you are talking shit.

Hell, I'm a physicist, and I also think Reggie was talking shit (about biologists, not about physicists' rationality).

Posted by: naturalist | July 3, 2009 12:31 PM

OT, but I found this video on YouTube while watching the Feynman segments. It's from Thunderf00T and compares the accomplishments over the last 1000 years of science vs religion. I love the music that Thunderf00T puts to the background of some of his stuff, especially this electronically infused one from Bladerunner.
Similiar to PZ, his YouTube criticisms of religion are devastating.

Hope this works:

http://www.youtube.com/watch?v=Gzdv2dsPPKw&feature=related

Posted by: Rey Fox | July 3, 2009 12:33 PM

No trolls on this thread. Feynman must be like kryptonite to them.

David Utidjian:
"This illustrates an aspect of humans and many other animals that the Christian god (or any "omniscient" god) lacks: curiosity. Omniscient gods can't be curious because they already know everything... What a boring existence that must be to already know everything that can be known. No new experiences, no surprises, no joy from figuring something out... boring forever."

This is why I found that "everyone becomes a God" thing that MormonMissionary was on about in the latest poll-crash thread to be so strange. Essentially, if you create your own world, you're unlikely to ever be surprised, whether you're limited by your own mind or an omniscient one. It just seemed like about the silliest childhood sandbox fantasy to base a religion on.

Posted by: Hairhead | July 3, 2009 12:58 PM

Feynman's clarity of thought cuts like a knife; he really was a genius. And there's an interesting story behind his public actions on the Challenger disaster panel. One of the colonels deep within the program had figured out what went wrong with the O-rings, but because of the secrecy oaths/national security bullshit/orders from higher up, he couldn't just come out and tell the members of the panel what had happened without having his career destroyed and ending up in jail. And he knew that because of the national security barriers, the panel would likely NEVER get the right answer if he didn't do something.

So one evening he invited Feynman over to his home and took him into his garage. He told Feynman that he just wanted him to look at and actually feel the items in question (the O-rings associated parts). Once Feynman actually physically got his hands on the stuff, he figured it out really quickly, without the colonel having to say anything, or break an oath. Feynman also got why the colonel couldn't say anything.

And that's one aspect of Feynman's brilliance. Tasking with a daunting problem not in his field, but given access to the items in question, he used the scientific method and quickly came up with an answer. And it showed his brilliance as a communicator when he avoided science-babble, but made a public, simple, physical demonstration comprehensible to the public.

It also took guts, as the panel was clearly intended never to find the explanation, and was there merely to cover the asses of some very powerful people and institutions.

Go Feynman!

Posted by: Greg | July 3, 2009 1:11 PM

As a youngster in a biology class whilst studying feline anatomy he asked for 'a map of the cat' instead of a diagram of feline anatomy. It's that kind of altered perspective that leads to insight.

Posted by: Anton Mates | July 3, 2009 3:25 PM

(I'm more a fan of the David Griffiths style).

Cosigned. Griffiths is a god among physics educators.

Posted by: FatherNature | July 3, 2009 4:07 PM

OT
Sarah Palin just resigned as Alsaka Governor. WTF?

Posted by: Feynmaniac | July 3, 2009 4:52 PM

Cosigned. Griffiths is a god among physics educators.

I think Griffiths' Introduction to Quantum Mechanics is the best undergraduate textbook on the subject.

Posted by: a_ray_in_dilbert_space | July 3, 2009 5:05 PM

Travis says, "Hell, I am a former physicist, computer scientist and work in bioinformatics...I have worked around lots of physicists, chemistists and biologists and I do not think he knows what he is talking about."

Uh huh. Dude, you're either a physicist or you aren't. If you were in fact a physicist, you would have said, "I'm a physicist working in engineering," or "I'm a physicist working as a WalMart greeter..."

You don't stop being a physicist, so from this I infer that you never were one.

Posted by: Katkinkate | July 3, 2009 6:13 PM

Posted by: Your Mighty Overload @ 30 "... Suffice to say, O2 generation has nothing to do with Co2 fixation."

I was taught that:

(6)CO2 + (6)H2O + energy C6H12 + (9)O2 (6 from CO2 and 3 from H2O)

I know the plant uses some of that O2 in producing other molecules (apart from the glucose above) and in respiration, but it doesn't discriminate by only using the O2 from CO2 and release the O2 from the H2O. Also the enzymes used to mediate the process are not consumed and so are not part of the basic calculation.

Or maybe this too is too simplistic?

Posted by: Travis | July 3, 2009 6:44 PM

Damn typos...D0, as in DZero. *sigh*

Posted by: John Morales | July 3, 2009 8:29 PM

[semi-OOT]

Hairhead @85, [about Feynman and Challenger]:

[...] And it showed his brilliance as a communicator when he avoided science-babble, but made a public, simple, physical demonstration comprehensible to the public.

Indeed! James Randi does a similar thing when debunking.
Some people are very special that way.

Posted by: pv | July 3, 2009 8:47 PM

A DVD of the original BBC Horizon programme, The Pleasure of Finding Things Out, is available from http://scs-intl.com/trader/feynman_video.shtm

I saw the original programme back in 1981 and have always regarded it as the best interview I've ever seen. It was just so riveting, and so simple - no special effects or artificial nonsense to make it "appeal" to anyone in particular. I bought the book of the same name, with a transcript of the programme, a some years ago and finally got around to buying my copy a couple of years ago. The best buy ever. And credit for the programme should go to Christopher Sykes.

Posted by: Feynmaniac | July 3, 2009 8:54 PM

Indeed! James Randi does a similar thing when debunking.

They actually knew one another. Randi:

The arrangement was for our mutual amusement; I would present him with brainbusters. I would pull some kind of trick on him when he was least suspecting, in the middle of lunch or some such thing. Then he'd probably spot that I was doing the routine with him and he'd say "Was that one of them?" and I'd say "Yes, that's one of them."

He had the privilege of asking any question about it, as long as the answer to the question was yes or no. ....... Feynman had used his spoon to stir his coffee, and I simply reached across the table and said "Watch this."

I picked up the spoon that he had just used to stir his coffee from the side of his saucer and asked him to hold it between his fingers. He looked very amused and he held it between his fingers. I gently manipulated the spoon between my thumb and my forefinger and it started to get flexible.

His mouth dropped open, and the spoon got more flexible and it twisted around and around and around it suddenly fell into two pieces.

Go here if you want to found out how it was done (Feynman did solve it).

Posted by: Crudely Wrott | July 3, 2009 10:35 PM

Back at comment 59 AJ Milne rattled my recollection by saying writing recalling archiving giving lyrics to my own history:

Mostly, I decided I just didn't like that taste of rank dishonesty in my mouth.

Spot on! my friend. By some rich and rare coincidence you have reduced (for me, that is) some chaotic corner of confusion to an honest human yearning; to not be lied to.

Would that I could have spoken so plainly at other times. I could have saved a lot of trouble not just for myself but for others as well who were equally undeserving of condemnation. Well, maybe.

Posted by: j a higginbotham | July 3, 2009 11:38 PM

(97) (6)CO2 + (6)H2O + energy C6H12 + (9)O2 (6 from CO2 and 3 from H2O)

I know the plant uses some of that O2 in producing other molecules (apart from the glucose above) and in respiration, but it doesn't discriminate by only using the O2 from CO2 and release the O2 from the H2O.

-----------
How about, simply
6 CO2 + 6 H2O (light)--> C6H12O6 + 6 O2

with the product being a sugar and the liberated oxygen coming from the water.

[In addition to the C3 mechanism there is a less efficient C4 mechanism which some plants in hot sunny regions use to minimize problems due to the oxygenase activity of RuBisCo.]

Posted by: Kevin Schreck | July 4, 2009 4:05 AM

A terrific clip. A good friend of mine introduced me to the brilliant Richard Feynman.

Posted by: qball | July 4, 2009 12:58 PM

Great clip. I love Feynman.

I'd recommend "Feynman's Rainbow: The Search for Beauty in Physics and in Life" to any fans. It was written by Leonard Mlodinow, who was a post doc at Caltech toward the end of Feynman's time there. It's a much easier read than his lectures and a really nice memoir.

Posted by: Si | July 7, 2009 4:34 PM

This one is well worth watching...

http://video.google.com/videoplay?docid=3164300309410618119

Posted by: Coriolis | July 16, 2009 2:22 PM

Actually, if you read his books he explains quite simply when he stopped being religious. One time when he was young the rabbi was talking about a jewish woman who was accused of being a witch and being burned. The rabbi then explained all the thoughts that she had at the time and so on. But then afterwards Feynman asked him - if she was burned to death, how do you know what she was thinking at the time? The rabbi replied that it was just made up to explain her state of mind or something along those lines. After that Feynman was rather dissapointed and didn't go back ;).