Richard Feynman's blackboard at the time of his death (1988) • Hacker News Board

Re: Richard Feynman's blackboard at the time of his death (1988)

#221

Post by Brian_K_White » Sat, Feb 22, 2025, 2:37 PM UTC

fouronnes3 wrote: post #34

gregschlom wrote: post #30

Earlier quoted context omitted.

> "What I cannot teach, I do not understand" And the corollary to that, from 17th century French writer Nicolas Boileau: "Ce que l'on conçoit bien s'énonce clairement, et les mots pour le dire arrivent aisément." - What we understand well, we express clearly, and words to describe it flow easily.

I'm french and I have a great memory about that quote. In high school my litterature and physics teachers had a disagreement about it, although I believe they didn't know about each other's point of views. Only us the students did, as they each hand waved great insights about the world with this quote. One was arguing, much like you, about the profound truth there is to it. The other was quick to explain that they pe…

I would say that if you can't explain on a blackboard how to ride a bicycle, then that simply means you do not understand how to ride a bicycle. You can do a thing without understanding it. I would guess very few bike riders really understand what all makes the act work even though they all can perform the act.

Maybe no one can learn how to ride a bike purely from a blackboard but that is a seperat issue about physicality.

But the quote is really about understanding, and the forces and effects that go into the act of riding a bike are both understandable and explicable. Anyone who understands them can describe them on a blackboard. So the quote holds water even in the case of riding a bike.

I would say anyway.

Maybe there are other examples and bike riding just wasn't the best example to invalidate the quote.

Re: Richard Feynman's blackboard at the time of his death (1988)

#222

Post by crazygringo » Sat, Feb 22, 2025, 2:41 PM UTC

everly wrote: post #78

JKCalhoun wrote: post #59

There's something rather sad, maybe poignant about it. It stands there as a testimonial to our brevity on this planet, to all that we will not see, do, understand. So it goes, I guess.

I'm reminded of a passage from the last psychiatrist blog: “One of the great insights of psychoanalysis is that you never really want an object, you only want the wanting, which means the solution is to set your sights on an impossible ideal and work hard to reach it. You won’t. That’s not just okay, that’s the point. It’s ok if you fantasize about knowing kung fu if you then try to actually learn kung fu, eventually…

> One of the great insights of psychoanalysis is that you never really want an object, you only want the wanting

...no it's not?

Much of traditional psychoanalysis has been superseded by modern psychotherapy. And I'm not even familiar with that idea being part of psychoanalysis in the first place. (And there are many schools of psychoanalysis that disagree with each other too.)

Quite frankly, it's not a great insight. It's perfectly fine to want something and then get it. Don't worry, you'll want something else afterwards. The idea that you should set your sights on an impossible goal doesn't hold up to the slightest logical scrutiny here. And a lot of people get disillusioned or burned out from trying to achieve impossible things and failing.

Modern psychotherapy is actually about aiming for achievable, realistic goals in your life. It's much more in line with the serenity prayer, in terms of aiming for realism:

God, grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference.

Re: Richard Feynman's blackboard at the time of his death (1988)

#223

Post by necovek » Sat, Feb 22, 2025, 3:07 PM UTC

jorvi wrote: post #151

hattar wrote: post #133

Earlier quoted context omitted.

https://royalsocietypublishing.org/doi/10.1098/rspa.2007.185...

> This conservative non-holonomic system has a seven-dimensional accessible configuration space and three velocity degrees of freedom parametrized by rates of frame lean, steer angle and rear wheel rotation. I always adore the split between how my brain does things instinctually, but making it arbitrary completely demolishes the 'natural' flow of it. Same with complex ball throwing / bouncing trajectory calculations.…

Sounds like a problem with your early math tutors: especially with geometry, all the examples you bring up have been taught with "what it means".

I mean, squares and cubes are just multiplication by the same factor: I distinctly remember even trapezoid surfaces, pyramid volumes being demonstrated by chopping and piecing parts together.

Re: Richard Feynman's blackboard at the time of his death (1988)

#224

Post by wholinator2 » Sat, Feb 22, 2025, 3:30 PM UTC

WalterBright wrote: post #143

gowld wrote: post #88

Earlier quoted context omitted.

You can't reasonably keep compressing centuries of progress into an intro series. I think you are describing undergrad vs graduate, not intro vs upper level, and even that is optimistic. Even tenured professors are still learning new things about what is already known to the world at large.

I suspect one can. This is because "progress" is pretty much never in a straight line from New York to San Francisco. It meanders all over the place, in circles, around the horn a few times, bumping into Africa, until it eventually blunders into San Francisco. Today, we can go directly from New York to SF in a straight line.

_Eventually_ you can take the straight line, probably. But the process needs time to contract the unnecessary steps. There's still things we haven't completely contracted, is my feeling.

Also, we shouldn't be so quick to throw away the original process of discovery. If our goal is to make scientists that can discover i think it'd be best to expose them to some of the real discovering. Like, the way fermi-dirac statistics is presented typically leaves out the rich process of discovery and understanding that took place, similarly with einsteins field equations. It leads young students into the thought that the big names are great, eldritch gods, completely incomprehensible in their genius. It begins to feel like you could never ever have made the discovery, because what you learned was not the discovery, it was the sum of 70 years since. I felt a great weight lift watching the sean carroll talk about _how_ Einstein made his equations. He explained the logic of each step, the assistance he needed to reach critical points, and generally made it human. I believe it was an RI talk. Then i remember some video about the process to find FD statistics to resolve the ultraviolet catastrophe and it was so enlightening. They aren't old gods, they're people that worked for decades to reach completely reasonable goals and we just don't teach it like that at all. It's incredibly discouraging to new students to never see that these people were mere mortals.

Re: Richard Feynman's blackboard at the time of his death (1988)

#225

Post by everly » Sat, Feb 22, 2025, 3:54 PM UTC

crazygringo wrote: post #222

everly wrote: post #78

Earlier quoted context omitted.

I'm reminded of a passage from the last psychiatrist blog: “One of the great insights of psychoanalysis is that you never really want an object, you only want the wanting, which means the solution is to set your sights on an impossible ideal and work hard to reach it. You won’t. That’s not just okay, that’s the point. It’s ok if you fantasize about knowing kung fu if you then try to actually learn kung fu, eventually…

> One of the great insights of psychoanalysis is that you never really want an object, you only want the wanting ...no it's not? Much of traditional psychoanalysis has been superseded by modern psychotherapy. And I'm not even familiar with that idea being part of psychoanalysis in the first place. (And there are many schools of psychoanalysis that disagree with each other too.) Quite frankly, it's not a great insight…

It's from a 10+ year-old blog post so I wouldn't expect it to be in line with modern psychotherapy.

It's an insight that has stuck with me since then and seems to strike a chord with others when shared, regardless of whether or not it's "great".

Of course it's fine to want something and then get it. Last night I wanted a Klondike bar so I walked to my freezer and got one. This misses the point entirely.

Plenty of examples of people getting what they thought they wanted and still feeling unfulfilled.

I appreciate your point about the serenity prayer, I think there's something relevant there for sure.

Re: Richard Feynman's blackboard at the time of his death (1988)

#226

Post by __s » Sat, Feb 22, 2025, 4:04 PM UTC

gitremote wrote: post #8

Molitor5901 wrote: post #3

Surely You're Joking, Mr. Feynman! is one of my favorite books. We lost him much too soon.

"the sham legacy of Richard Feynman" is about Feynman being famous because of this book rather than because of his physics. The YouTuber, an obsessed physicist who had spent months reading all Feynman books, provides a critical analysis and explains the cultural impact of "Surely You're Joking, Mr.Feynman!" https://m.youtube.com/watch?v=TwKpj2ISQAc

Overall seems good, but I find it interesting she says it teaches to always be the smartest person in the room when the book often reflected Feynman as being somewhat simple, going on about reliance on mental tricks in comparison to his colleagues who he felt were much more talented. Or instances where he found himself out of his depth & got lucky (pointing at some random thing on a diagram to figure out what it is without asking, happens to get people he's with to rubber duck debug an actual problem). Which may support her observation of Feynman bros who might find this relatable

This all comes back to the observation I've made working with competent people, which is that we're all stuck trying to solve problems with the computational power of a slab of meat

(she later goes on to address this modesty as being underhanded)

(continued watching, two hours in now, this is great work)

Re: Richard Feynman's blackboard at the time of his death (1988)

#227

Post by crazygringo » Sat, Feb 22, 2025, 4:15 PM UTC

everly wrote: post #225

crazygringo wrote: post #222

Earlier quoted context omitted.

> One of the great insights of psychoanalysis is that you never really want an object, you only want the wanting ...no it's not? Much of traditional psychoanalysis has been superseded by modern psychotherapy. And I'm not even familiar with that idea being part of psychoanalysis in the first place. (And there are many schools of psychoanalysis that disagree with each other too.) Quite frankly, it's not a great insight…

It's from a 10+ year-old blog post so I wouldn't expect it to be in line with modern psychotherapy. It's an insight that has stuck with me since then and seems to strike a chord with others when shared, regardless of whether or not it's "great". Of course it's fine to want something and then get it. Last night I wanted a Klondike bar so I walked to my freezer and got one. This misses the point entirely. Plenty of exa…

> Plenty of examples of people getting what they thought they wanted and still feeling unfulfilled.

Right, I think that's what might be striking a chord.

Modern psychotherapy would tell you that you'd picked something thinking it would solve problems that it never would. A classic example is that if you achieved a certain career objective or measure of success, you would feel loved and approved of and worthy. And then when you achieve it, you don't.

The answer is absolutely not to pick a goal you can't achieve. That's completely wrong.

The answer is to understand that career or professional success will not make you feel loved. That if you feel like you have an unmet need for love and approval, you need psychotherapy to understand where that is coming from in terms of your childhood, current relationships, etc.

And then you can reframe your professional or career goals as something else entirely. And when you reach one, you can feel proud and then set another one. You won't have a feeling of emptiness or unfulfillment, because you'd never set unrealistic expectations for what that achievement would provide.

Re: Richard Feynman's blackboard at the time of his death (1988)

#228

Post by localhost » Sat, Feb 22, 2025, 5:18 PM UTC

JKCalhoun wrote: post #144

gowld wrote: post #81

Earlier quoted context omitted.

If you are calling Richard Feynman "profoundly unwise" and "endlessly futile", you might need to do a bit more reflection on the grounding for your opinion.

Feynman has a comment in one of his two autobiographies where he describes an argument with an artist friend — about, I think, the beauty of a rose. His friend believed that "dissecting" the rose, breaking it down to its biological components chemical processes, took away from the beauty of the rose. Feynman disagreed — couldn't understand how knowing more about the thing could possibly take away from it. It was the…

You can listen to him talk about it!

https://www.youtube.com/watch?v=ZbFM3rn4ldo

Re: Richard Feynman's blackboard at the time of his death (1988)

#229

Post by xanderlewis » Sat, Feb 22, 2025, 5:18 PM UTC

MisterSandman wrote: post #167

Shorel wrote: post #163

Earlier quoted context omitted.

They don't, and they can't. They don't even know that they can't. The mathematics mindset and the programming mindset could not be more different. Writing a mathematical proof is similar to writing everything from scratch each time. However, and this is a serious affirmation: learning to write mathematical proofs will make anyone a much better developer, because of the changes in the mental processes involved in the…

What? Every mathematical proof is built on top of other proofs, especially when you look at research that is happening today. Mathematics and Computer Science mindsets are closer than most other pairs of academic streams. There’s a reason why so many universities have their CS departments under their Math Departments.

These days it’s more like math departments under CS departments (which are seen as highly important, as a CS degree is more fashionable than a maths one and mathematics is seen as an abstruse academic pursuit in the worst sense and a financial sink rather than a source).

It’s true that (almost) every proof is built on top of others, but this is not the way mathematicians learn their craft — you do have to start at the bottom.

The average programmer, on the other hand, has never been anywhere near the hardware or, these days, the software near the bottom.

Re: Richard Feynman's blackboard at the time of his death (1988)

#230

Post by vinceguidry » Sat, Feb 22, 2025, 5:20 PM UTC

drewzero1 wrote: post #188

BobaFloutist wrote: post #110

Earlier quoted context omitted.

Those both seem much easier to me than what I usually struggle with: Transported back to a pre-industrial time, is any of my technological knowledge or understanding even remotely useful? Like, sure, germ theory is great I guess, but I have no idea how I'd begin to explain the internal combustion engine (which I'm fairly sure requires pretty advanced metallurgy) let alone something as esoteric as solar panels. Hell,…

This thought experiment reminds me of Mark Twain's novel "A Connecticut Yankee in King Arthur's Court", in which the main character is a 19th-century American man transported back to 6th-century Britain. He used his experience in firearms manufacture to introduce modern weapons and had bicycles constructed for the knights to ride around on. I always thought it was pretty farfetched that he'd be able to recreate such…

Nineteenth century kit wouldn't really be all that difficult to replicate with the materials available in the early middle ages. Even the precision stuff of the time, you can make a surface plate just by scraping an iron sheet. With a surface plate you can make everything else you need. The hard part would be higher quality metallurgy, but it's certainly doable, the Chinese were making cast iron as early as 5th century BCE. Even steel was possible with even Bronze Age equipment.