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Feynman on explanations (lesswrong.com)
202 points by gwern on Jan 8, 2012 | hide | past | favorite | 54 comments



"But it's in 240p! Nobody likes watching 240p videos. So I transcribed it."

I've watched and shared this video several times. The video is just fine in 240p. You miss out on Feynman's delivery and style when it you just read it as text.

I think it's from a BBC documentary; the other parts are on YouTube as well. The discussion about how humans model or understand really big/really small numbers is especially interesting.


I'd just like to point out that "But it's in 240p!" wasn't entirely serious. I transcribed it because I thought it was a really good answer to the question and more people would see it that way, and I'd gain some karma a Less Wrong to boot.


I, for one, appreciate it. Thanks for not wasting my time.


I'm sure it's a fine video, but I prefer transcripts since it doesn't require me to get out my headphones. So I'm glad he did it.


The resolution complain is particularly strange when you figure that if a transcript is allegedly good enough, then surely you can just listen to the video instead.


On YouTube audio quality degrades with resolution. I avoid watching 240p videos whenever I can first and foremost because of their horrible audio.


In this case I see absolutely nothing wrong with it. This isn't classical music after all, it's a guy talking.


Yeah, AM radio is still used for even the largest talk shows, and it's far from perfect quality (which is why AM is rarely used for music, but it's fine for speech). Likewise landline phones especially long distance calling was never all that great sound quality but it never stopped you from picking up the phone when someone called.


I can’t stand it. Judging from the transcript, at least whoever did that seems to feel the same. (Since humans are not terribly dissimilar I would be willing to guess that actually many other people feel the same.)

That’s all I’m saying.


Maybe you can 'just listen'. I'm hard of hearing, please don't presume to speak for me.


I read it in Richard Feynman's voice. :)


Totally agree. I was perfectly happy to watch this in 240p, Feynmann was such a legend.

When you think about it, and maybe I feel like this because I just watched Feynmann, but it's totally insane that we can watch videos on the Internet at all! Even in 240p, which apparently, nobody likes.


Exactly. A transcript is 0p which is decidedly worse.


If p stands for "lines", how can you claim the text is written using 0 lines?


Surely you know that 'p' in relation to video is an abbreviation for pixels. And 1080p video isn't the equivalent of specifying "font-size: 1080px" in your transcript's CSS.


I don't think it stands for "pixels". It stands for "progressive", as in "progressive scan". As opposed to "interlaced scan", which is what 1080i refers to.

Why do you think I said it was equal to specifying the font-size? As I said, it practically refers to the number of lines. Font-size has nothing to do with that, directly. You can't specify the number of lines in CSS, AFAIK. CSS is for styling. Lines are content.

Anyway, I was just trying to point out how nonsensical it is to compare the "resolution" of a text with a resolution of a video. And if you do, I think it's interesting to think about that the number actually is dynamic, as is, it depends on the container and so on. Which is actually quite an appropriate analogy, since it is often easier (IMHO) to think profoundly about something you're reading (where you control the tempo), in comparison to a video, where you constantly have to follow their tempo. Yes, you can rewind, but if you do that, I think you'd agree with me that it'd be easier with a transcript.


My 0p comment is silly math (take 240p, remove 240p worth of video, the remainder is 0p) to make a point that 240p is actually good enough to watch since what the author presented cannot be watched at all.

Yes there are many benefits to having a transcript, but those arguments apply just as much to 1080p as to 240p.


Zero lines of video?


A professor told me once, "Physics is about what happens. If you want to know why, maybe try going to church."


If you haven't watched these "Fun to imagine" with Feynman videos from YouTube, I really recommend them. You just can't capture his joy and passion with a transcript.

"Fun to Imagine" playlist: http://www.youtube.com/watch?v=v3pYRn5j7oI&feature=BFa&#...


Feynman, I guess because he interacted a lot with laymen (an lay-women) knew that the knowledge frame of the audience is very important. If you think this is obvious, wait till you try to explain internet addresses, cloud storage, etc. to your mom (or grandma), or as in the well-known case (http://tomayko.com/writings/rest-to-my-wife) the REST protocol to your wife.

It's very hard to estimate the level of explanation that will actually convey information to the person asking teh question while at the same time keeping them interested.


It all gets summed up in the last sentence, which is really a killer:

> But I really can't do a good job, any job, of explaining magnetic force in terms of something else you're more familiar with, because I don't understand it in terms of anything else that you're more familiar with

I've never heard that impedance mismatch being told in such clear, humble words. Basically, he's saying "I know things in so much detail that I can't in all honesty imagine wrongful analogies, let alone present them to you".


He's not saying that he "knows things in so much detail that he can't imagine wrongful analogies". He's saying that "magnetic force is different from anything you are familiar with", so you have to learn it as something new, not by analogy.

Feynman does (explain a little bit of) Quantum Mechanics by analogy (photons are spinning clocks), but goes on the say you have to learn a truly ne wmodel to understand more deeply.

See also: Dijkstra's "On the cruelty of really teaching computing science: http://www.cs.utexas.edu/~EWD/transcriptions/EWD10xx/EWD1036...

> It is the most common way of trying to cope with novelty: by means of metaphors and analogies we try to link the new to the old, the novel to the familiar. Under sufficiently slow and gradual change, it works reasonably well; in the case of a sharp discontinuity, however, the method breaks down: though we may glorify it with the name "common sense", our past experience is no longer relevant, the analogies become too shallow, and the metaphors become more misleading than illuminating.

There are lots of gems in that essay, such as this:

> We can view the program as what turns the general-purpose computer into a special-purpose symbol manipulator, and does so without the need to change a single wire (This was an enormous improvement over machines with problem-dependent wiring panels.) I prefer to describe it the other way round: the program is an abstract symbol manipulator, which can be turned into a concrete one by supplying a computer to it. After all, it is no longer the purpose of programs to instruct our machines; these days, it is the purpose of machines to execute our programs.


Excellent. But there is another important situation to deal with, and that is when the interrogator is asking dishonestly, usually to reenforce some prejudice. Personally I have found the best way to deal with such discussions is not to have them, for the simple reason that my contempt for willful ignorance compounded by dishonesty ultimately outweighs my love and joy at explanaition.

Practically speaking, the impact of walking away from such loaded discussions is minimal, because in a healthy society generally these dishonest interrogators' views and opinions simply don't matter (apart from the odd grade-school curriculum debacle). They don't matter for two reasons: first, normally the point of understanding (e.g. evolution, or even magnetism) is not necessary to the persons practical day. Second, a healthy society tends to disregard the views of the dishonest.

This is an argument from practicality. Know when to walk away from some debates.


I agree except for the relatively few people who are familiar with this type of discourse. Those that are good at it can destroy the original framing attempt and reframe it for their own purposes. Newt Gingrich is quite good at this.

I simply don't have the verbal chops to compete. Newt studied rhetoric as I recall.


Another amazing line: "So I am not going to be able to give you an answer to why magnets attract each other except to tell you that they do."


I love this about his style. If he couldn't explain something in a manner simple enough for the audience to understand, he didn't explain it at all. There is no simplified yet incorrect version offered.


By far the best video of Feynman is "The Distinction of Past and Future", which is one of his lectures in the cornell messenger series in 1964 (i think).

http://www.youtube.com/watch?v=_Kab9dkDZJY


"Because some things are, and some things are not!" Louis CK does a hilarious job describing how it is digging down the "why" hole: http://www.youtube.com/watch?v=4u2ZsoYWwJA


the whole video is hilarious, but for the hurried amongst us, the 'why hole' bit is around 7:10

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


I love how he covers everything from:

"For example, Aunt Minnie is in the hospital. Why? Because she went out, slipped on the ice, and broke her hip."

to:

"You know you can't put your hand through the chair; that's taken for granted."

What an incredible mind.


Watch the rest of the "Fun to Imagine" videos, and you'll hear about why trains don't need differential gears and how the mass of trees comes out of the air instead of the ground.


While that we are touching on Feynman, I thought this bit was interesting (just 1:26 long)

Richard Feynman on Computer Science - http://www.youtube.com/watch?v=lL4wg6ZAFIM&feature=relat...

I believe he has a point, I don't know if term Computer Science is the best choice of words.


I have an off topic question. I'm not a native English speaker, and I find the way Feynman is pronouncing t, d, k, g, p and b consonants very interesting. He uses hard attacks and hard stops. Does anybody know if there is a name for that ? Maybe a regional thing or just his way to speak ?


It's regional. He grew up in Queens, New York City. His dialect is pretty common.


Reading a transcript is just not the same as watching Feynman talk, which is such a delight. 240p or not, I encourage everyone to watch the video.


I should refer you to the Feynman Series (from the Segan Series creator) http://www.youtube.com/playlist?list=PL92F9FC91BBE2210D&...


Yay, Feynman!

If this has whet your taste for his wonderful explanations, I highly encourage you to take a look at his lecture series made available by Microsoft Research on Project Tuva[1].

[1]http://research.microsoft.com/apps/tools/tuva/index.html


Don't bother going to the Microsoft site, where you have to install Silverlight to watch a video, just use Youtube to watch the 7 part series:

http://www.youtube.com/results?search_query=the+character+of...

I am actually half-way through watching them and as with all Feynman lectures they are a real joy to watch.


I think that people's tolerance for simple metaphors is related to their level of curiosity. I'm pretty sure that many people would be satisfied with a "rubber band" explanation even though it doesn't fit. The more curious person though would probably, as Feynman said, want to know why rubber bands behave in the way that they do, and then the metaphor would break down.

This to me tells me two things about Feynman:

1) He was a man of great integrity

2) He wanted people to be more curious about the world


I dig his neverending questionnings and explicitness.


[deleted]


Your missing why he is doing this. He is acting like a professor giving a lector in that interview and being redundant. The important take away is how to talk to the slowest person in the room or in this case the million+ people watching that interview.

PS: I wish more scientists would act this way when interviewed. Global worming, simplest explanation for the 100+ million direct and indirect measurements of atmospheric chemistry and temperature we have taken that fits in with the basic physical laws. Don't agree with it? How do you discount the discrepancy of absorption spectrum as you change atmospheric chemistry etc?


> Global worming, simplest explanation for the 100+ million direct and indirect measurements of atmospheric chemistry and temperature we have taken that fits in with the basic physical laws.

Umm, you're missing an important detail. The additional absortion is orders of magnitude too small to produce the predicted temperature increases. The predicted temperature increases are based on feedback and some other effects, which took a decade off.


No, direct retention of radiated infrared energy is vary important. There are plenty of feedback cycles, but they don't all warm the planet so it really does take a lot to shift each of those 0.1C increases. People are directly responsible for ~1/4th of all carbon dioxide in the atmosphere which is not exactly a minor change. (We are around 391ppm and adding a little over 2pmm / year.)


> People are directly responsible for ~1/4th of all carbon dioxide in the atmosphere which is not exactly a minor change.

That huge change in CO2 is not a huge change in the atmosphere's ability to retain energy because (a) CO2 concentrations are fairly low and (b) other gasses have a much larger effect.

Note that the atmosphere's ability to retain energy is not dependent on where the CO2 comes from.... I mention that because the earth has had much higher CO2 concetrations.


Climate change is a better term to describe the effects of changes in atmospheric chemistry. It's more accurate since most scientists agree that the long term effects are extremely difficult to predict.


Well said, except it is not true about the ice melting under pressure -- a weight of a human is not enough (same holds for skating). The ice is slippery because of its anomalous behavior on the boundary, which is still not fully understood.


Yup, but I think in the 80's it was the standard explanation.

http://www.nytimes.com/2006/02/21/science/21ice.htm


This is why scientists don't get invited to cocktail parties


Does anyone know where I can find the entire talk he gave?


The comment on the youtube video links to the entire series on the BBC: http://www.bbc.co.uk/archive/feynman/

Not sure if available to watch outside UK but they are the same as on Youtube, just better quality.


Not this one, I meant the one from Bell Labs.


Can anybody explain me how to make an apple pie from scratch?


Well you start with all the matter and energy in the universe compressed to a point...




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