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Comment by sykh | Hacker News Reader

Feynman was wrong on his view. The same thing could have been said of him and physicists. Oh, you spent your time memorizing formulas when it could be looked up in 15 minutes.

This is a nonsensical point of view for two reasons. People in areas of their expertise tend to know a lot in that area off the top of their head because they have encountered this stuff so much that it has become memorized. That memorized knowledge comes from experience not a memorization exercise. It’s also nonsensical because if you didn’t have a core set of knowledge memorized in your area of expertise and instead relied on spending 15 minutes looking up each fact necessary to understand a given situation you’d end up wasting your whole day just trying to understand the meaning of the problem.

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I'm uncertain how it was in Feynman's day in particular, but in my physics course you are given essentially all relevant formulas during any exams. You have to understand what they represent, and may end up remembering some of the more useful formula off the top of your head from using them often, but there is no rote memorization required.

There are also dozens of constants involved that are possibly a better analog, very few of which end up memorized.

And by the time you are ready to get a degree in physics it will no longer be necessary to give you those formulas in a test. You have used them so often and understand them so well that a formula sheet isn’t necessary.

You have missed the point of my comment. Do you think Feynman lacked a vast amount of physics knowledge that he memorized (to use his phrasing)? Part of acquiring expertise in any area is the fact that you end up storing lots of information about that area so that you don’t need to look up every little detail or fact.

If you are going to have a serious discussion with biologists about cell processes you need to have lots of knowledge, names, etc. at the ready. Can't go looking up every little thing as you go along. It would be impossible communicate if you did that.

Feynman was being a jerk with that comment. His dismissiveness reminds me of comment that a well respected mathematician once made. “Quantumn mechanics is just such and such theory in dimesion 1.” Only ignorance allows one to hold such a belief.

In addition to that, I think it’s generally not a good teaching technique to belittle your students, even if they show a bit of immaturity.

> “Quantumn mechanics is just such and such theory in dimesion 1.”

Well, quantum mechanics is "just" 0+1 quantum field theory which is actually a good insight and not at all dismissive.

It is dismissive because if it was just that then knowing the mathematics would be sufficient to do research in theoretical quantumn mechanics but it isn't. One needs to know the physics and have physical intuition. To say that theoretical quantumn mechanics is just a small branch of mathematics is ignorance. It is not insightful at all.

Is commutative algebra just a branch of set of theory? Are set theorists generally equipped to understand research papers on Galois Cohomology? No. Set theory is used in these areas but to suggest that these areas "are just aspects of set theory" is not all insightful.

I don't understand the complaint here, Quantum Field Theory is physics just as much as Quantum Mechanics?

The mathematician who made the quote I mentioned said that quantum mechanics was just <some branch of mathematics that I’ve forgotten> in dimension 1. I don’t know what quantumn field theory is. If it is a branch of physics then it’s not the theory the mathematician I referred to mentioned. Some mathematicians view mathematics as superior to physics and are dismissive about physics. They tend to believe that since they mastered mathematics then learning physics is easy.

> It is dismissive because if it was just that then knowing the mathematics would be sufficient to do research in theoretical quantumn mechanics but it isn't.

This not at all the same. QM is a special case of QFT.

> To say that theoretical quantumn mechanics is just a small branch of mathematics is ignorance.

It’s not. That statement is objectively true.

> It is not insightful at all.

It is.

https://en.m.wikipedia.org/wiki/The_Unreasonable_Effectivene...

> Is commutative algebra just a branch of set of theory? Are set theorists generally equipped to understand research papers on Galois Cohomology? No. Set theory is used in these areas but to suggest that these areas "are just aspects of set theory" is not all insightful.

Intersection (overlap) is not the same as containment, so I have no idea why you’re bringing this up.

Isn’t it true that commutative algebra is contained within set theory? Aren’t all the objects sets?

> Isn’t it true that commutative algebra is contained within set theory? Aren’t all the objects sets?

Sets are one way (among others) to encode such mathematical structures. This doesn’t mean these structures are sets. For example, is the empty set an element of pi? This question is meaningless because the answer would have to depend on the encoding being used, and not on the properties of pi itself. It’s imposing additional structure above and beyond that of the mathematical structure in question.

See here for more discussion: https://news.ycombinator.com/item?id=16080027.

A ring is a set. So is a group. At least this is how almost every working commutative algebraist views things. Category theory and its like are gaining traction but the objects are still viewed as sets.

> A ring is a set.

No. It is a set together with additional structure. Without this additional structure you just have a set, not a ring.

> So is a group.

Again, no. It is a set together with additional structure.

Note: The collection of all groups is not even a set!

There is little rote memorisation required in physics because we have formulated it based on logical ideas, intuition, and fundamental principles. You can understand, not memorise.

Biology is immeasurably harder than physics, the systems so much more complex and opaque and non amenable to fundamental explanation. Rote memorisation is a must.

This is true at the surface level. However, biological systems are organized by principles. Source: degrees in both fields.

Memorizing large numbers of facts give way to understanding and intuition in my experience. It’s quite similar to how a chess player’s experience regarding strategy starts out by exhaustively enumerating potential futures and eventually turns into an intuitive understanding of future plays and how training a neural network leads to a high dimensional manifold representation of a concept.

Isn't it at least literally true that biology encompasses all of physics, plus some added complexity/emergence on top of that?

Biology is a huge field so I don't mean to speak for all of them. My wife is doing a PhD in Immunology so I know that at least for her, she's thinking in a whole different abstraction level. She's not that concerned about the physics in her day to day experiments.

Good point. It really depends on what area in biology you're in. For immunology, pathology, and, honestly, most subfields, you're closer to phenomenology than emergence.

I will say that I'm skeptical of a lot of the work done in biology in relation to networks and complexity. It's often either done by those without sufficient mathematical background (and, typically, wholly statistically invalid) or a bunch of hand-wavy, feel-good nonsense for a sexy tagline by those who should know better.

Better work is done by researchers in complexity who analyze biological systems.

>Biology is immeasurably harder than physics

Statements of this form are essentially always false: basically everything has the same difficulty because the standards for what constitutes progress in a field are set according to what the people working in it can do on average.

It's easy to write down what you thought of Infinite Jest, but in order to achieve any special success as a critic you're going to have to beat out everybody else that's doing the same thing. That makes it very hard. Likewise in an alternate universe where physics was easy, the standards for how much you had to say in a paper would rise until the average paper was about as substantial as it is now.

>"the standards for what constitutes progress in a field are set according to what the people working in it can do on average."

For example, in physics they require p < 3e-7 for a discovery. While in biology it is p < 0.05 and sometimes even p < .1 is allowed.

But very different things are being measured--comparing them this way is very flawed.

Not sure what you mean but my post was a sarcastic comment about how people choose an arbitrary level of significance so that the "right number" of "discoveries" can be published each year.

If there is a lot of data they would have too many "discoveries" (it would seem too easy) so they need a more stringent threshold. If the data is very expensive they would have too few "discoveries" so the threshold gets relaxed.

Pardon, I have a weak ability to detect sarcasm before finishing my first coffee. I fully agree that p-value limits are arbitrary, and what one is examining can greatly impact the interpretation of 'significance' or not. As you imply, data can be inflationary , incrementally increasing in volume and decreasing in value.

Physical sciences have the benefit of being pitted against reality. A physicist a generation ahead of his time can make predictions about reality which will prove him correct, even if nobody else can understand what he's saying. A literary critic who truly understands more than everyone would have no recognition to show for it if everyone else were simply incapable of understanding it.

>A literary critic who truly understands more than everyone would have no recognition to show for it if everyone else were simply incapable of understanding it.

A successful critic isn't a critic, they're an author that writes for whoever is making them successful. So the critic at the top of academia would be the best at writing criticims that people understood: no garuntee of understanding the most, but that's still a skill that, say, Feynman would find it hard to replicate. The heirarchal nature of almost everything garuntees that there will always be "the best," and that they will be hard to beat, regardless of how much it means in the grand scheme of things. Finally, the scarcity of grant money means that participating in any field means beating the best: a regulatory effect that's at the center of the discussion.

It's true for formulas, but not for muscle names. You need to know what muscles do and their context, but names are just useful for communication, not analysis.

Also true of street names, you just need to know physically where your town's various businesses are and where your people live. But still you kind of have to know most of the street names off the top of your head to function properly.

Besides, I think most muscle names are literally just derived from their position on the body and their movement range, so their name and their function are closely linked.

> But still you kind of have to know most of the street names off the top of your head to function properly.

I know 10 street names in my city. The rest, I look up.

Well, I used to, now I use the GPS.

Note that I do think you are more efficient if you know the street names and where they are.

But I also do think the time and energy requires to learn 100 street names and position in my city can be better used for something else.

What if you were a cop? Would you criticize a cop who has learned the streets? Shouldn’t a biologist who is at a talk about felines understand the biology of felines without looking it up in a book?

Feynman's criticism shows an ignorance on his part.

It's not about knowing, it's about learning artificially.

> What if you were a cop? Would you criticize a cop who has learned the streets?

I would appreciate cops learning anything, but given they got a GPS and older colleagues knowing the streets name by habit, I'd prefer they spend time learning the law. The names will come naturally with practice.

> Shouldn’t a biologist who is at a talk about felines understand the biology of felines without looking it up in a book?

See that's the problem here. You assume you can't know the biology of felines without knowing all the names of all muscle by heart.

It's like saying I can't understand a program if I don't know all the functions of it's API. And while after years of programming I know a lot of things without needing to look them up, I never learned nor will learn any listing by heart. It's a waste of my time. I need to understand algo, complexity, interractions. Names are just an interface, useful, but not required for modeling.

Same things for you biologist. He must understand the interractions between the organs, the chemistry, the musculo-skeletic chain. Naming all the muscle is just a bonus, and now that we have books and computers, it's not a priority anymore.

Does knowing stuff by heart makes you more efficient ? Does it make you a better pro ? Yes, but only if the more important stuff are understood.

And if you are a student, mindlessly learning all names is completly a waste of time. Espacially since they are going to forget most of it after graduation, and learn it back again on the way.

You can’t converse with an expert on felines without knowing the names. There are simply too many parts of the body. You have to name them in order to communicate. There’s a reason for the names. It’s nit like someone sadistically decided to give a name to each part. Go ahead have try having a conversation with someone who knows the names and functions of each muscle where you don’t. Looking up each term is not efficient.

I’ll take a cop who knows the streets over one who has to look up on GPS. Cops chasing a suspect have report on their progress so that backup can reach them. What do you think they’ll do? Pause every 20 seconds and look up GPS coordinates?

Feynman's critique was born of ignorance. He criticizes people for knowing the parts of the cat. In the lecture they criticize him for drawing the map of the cat. They know this already. Feynman does not. He is not at their level and instead of admitting this he makes an ignorant quip.

Virtually all knowledge is an easy internet search these days. This has not diminished the need to know, have memorized, terminology.

Let S be an infinite dimensional ring extension of R with R a commutative Noetherian ring with identity. Under what conditions is S flat as an R-module?

If someone gives a talk on commutative ring theory and the above is the topic they best not waste everyone’s time by looking up the meaning of each word and writing it on the board. Such a person exposes that they aren’t learned enough in the field to be giving a talk.

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