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Terry Tao on some desirable properties of mathematical notation

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Re: Terry Tao on some desirable properties of mathematical notation

#91
Is it just me, or does probability theory in general have fairly terrible notation? Ambiguity between random variables and their distributions because of them simply being distinguished by being upper-case or lower-case, writing likelihood functions alternatively with an L() or p(), and using p() (with different arguments) to refer to different probability distributions. Perhaps I'm just having such a difficult time grokking probability theory because it's just difficult stuff, but I often find myself immensely frustrated with the notation.

Re: Terry Tao on some desirable properties of mathematical notation

#92
post #19

Earlier quoted context omitted.

> Mathematical notation presumably mostly makes perfect sense to the kind of people who deal with mathematical notation all day long. Maybe the overuse of opaque names leads to self-selection of who becomes a mathematician? Single-letter non-descriptive variable and functions names would “make sense” to programmers who use it all day long too — but that alone doesn’t make it a good idea.

I'm both a programmer and a mathematician. Mathematics is written in English (or another human language) plus added symbols. The symbols are what we refer to as the notation. It's not comparable to programming language. Here the words are equal to the symbols. Also, no better notation could help you understand most modern mathematics. There's no better choice of symbols or names that will help you understand Galois t…

but put it the other way: can you contrive some extremely bad notation to make it harder to understand Galois theory?

Re: Terry Tao on some desirable properties of mathematical notation

#93
post #79
post #18

Difficulties, if any, perceived or real, arising in connection with notation, are usually incomparably smaller than those presented with the subject itself. (Personally, I only wish mathematical notation were better integrated with software in general and programming languages in particular.)

Not true at all, there are several times I've attempted to read through a textbook only to be stopped by notation because something was introduced prior to being referenced, or notation is overloaded with multiple meanings. I consistently have run into "perceived or real" confusing mathematical notation as an impediment to learning in a way that programming languages have never, ever caused me. Does no one else feel…

A lot of people say this, but if I were to sit next to you and tell you what the notation means whenever you asked, would you instantly understand the concept? I don't think so. You still need to do work on your own with the concept before you can get to any understanding.

Say, you come across this symbol: ζ(s)

And you asked me, what does it mean?

Oh, that's probably the Riemann zeta function (it could be other things, but that's probably its most famous meaning).

Would you be like, ah, now I understand it all!

I sincerely doubt just knowing the English words for the symbols (and all mathematical notation is just shorthand for English, or whatever other natural language; it can all be read out loud) would get you that much further along. I could give you one of several possible equivalent definitions, but you still wouldn't really know much of anything. I could start explaining some things about primes and how they relate to the Riemann zeta function, and you'd still be in the dark. I'd have to talk about the prime number theorem and estimates and complex analysis and a whole bunch of other things before the Riemann hypothesis even started making sense. In fact, people have written entire books just trying to explain in the most accessible way possible what that one symbol is:

https://www.wstein.org/rh/

I believe what's going on is that a lot of people who find notation to be the first stumbling block are trying to learn mathematics in isolation, without the benefit of a mathematical community to be able to talk to. You pick up a book, see a bunch of weird symbols, blame the notation, you put it down. But people who train for mathematics specifically rarely learn that way. Mathematics is a social activity, you talk to other people, you read the symbols out loud to each other on chalkboards or side-by-side as you scribble notes on paper or on a napkin. You talk to each other a lot, pronouncing the symbols as much as you write them down.

The notation is a very superficial obstacle. Notation is very incidental, malleable, almost irrelevant (or as mathematicians might say, non-canonical or not natural). If notation is your biggest obstacle, there's a lot more underneath that you probably don't have enough experience with.

Re: Terry Tao on some desirable properties of mathematical notation

#95
post #91

Is it just me, or does probability theory in general have fairly terrible notation? Ambiguity between random variables and their distributions because of them simply being distinguished by being upper-case or lower-case, writing likelihood functions alternatively with an L() or p(), and using p() (with different arguments) to refer to different probability distributions. Perhaps I'm just having such a difficult time…

I don't really know, I'm not an expert in the field. What I do know, is that I can usually get almost anything written in English in a statistics text, but when it goes mathematical notation I really struggle even with the simplest of concepts.

Type theory is a little like that, at least from some authors that - although the are is well suited for symbols - kind of goes a little off the rails using seven different kind of arrows and all the symbols in at least three different alphabets, instead of maybe just write covariant, or even an abbreviated form adjecent to the arrow?

Re: Terry Tao on some desirable properties of mathematical notation

#96
post #49

Mathematical notation is great at facilitating formal manipulations. This is its critical feature, and without it we would get stuck at the level of ancient mathematics. This is the reason it was invented a few hundred years ago in the first place. That said, I find that notation is often abused in texts as a mere substitute for the normal human language which, while allowing to compress the text, does in fact nothin…

there are some academic disciplines which are extremely guilty of this. they are the ones that are insecure about their status as a science.

Re: Terry Tao on some desirable properties of mathematical notation

#97

Tao a rare person with 200 IQ

Almost ten years ago I was working on an interesting Linux multiboot system, googling to find far-from-default grub operation hints.

I think it can be agreed the present grub documentation is very broad, with only a few undocumented features, but still not very deep even on the default operation. Grub was also undergoing more rapid change at the time.

Came across a message where Tao had explained a concept like no other, and after what I had seen it was clear to me he understood it like no other, so it was purely logical. He knew more than the documentation. I didn't know he was a widely recognized mathematician or anything, I just thought he was a very bright computer scientist on a message board.

There were only a couple sentences that nearly applied to my system, within a couple paragraphs on his solution to a different problem.

There was no useful answer for me yet so I moved on.

Googled to exhaustion that session with no code changes to make, but I looked at it again and it was the only tab I kept open, even though Tao did not show the direct way forward for me at all, everything else was actually useless.

Next day I read it again, scrutinizing it over & over for an action I could follow through with, wishing someone had posted equally straightforward advice for my particular situation.

No such luck, but it inspired me to go forward in a similar fashion.

Mostly use both grub and syslinux as separate alternatives to boot my distributions ever since.

For years I've felt like I couldn't have done it otherwise.

And with Windows, grub or not, I ended up bringing more reliability to my employer.

Fairly recently I found out Tao had started out as a mathematical child.

That was incredibly helpful.

He actually communicated the unique abstract concept I needed without even knowing the problem and without intentionally trying.

I imagine he made up his own notations quite a bit before he carefully adopted the various professional terminologies.

Re: Terry Tao on some desirable properties of mathematical notation

#98
post #49

Mathematical notation is great at facilitating formal manipulations. This is its critical feature, and without it we would get stuck at the level of ancient mathematics. This is the reason it was invented a few hundred years ago in the first place. That said, I find that notation is often abused in texts as a mere substitute for the normal human language which, while allowing to compress the text, does in fact nothin…

"does in fact nothing to help the reader better understand what is being said"

For a mathematician it is the opposite, they just wish it would be written with symbols so that they could know precisely what the book is trying to say

Re: Terry Tao on some desirable properties of mathematical notation

#99
post #49

Mathematical notation is great at facilitating formal manipulations. This is its critical feature, and without it we would get stuck at the level of ancient mathematics. This is the reason it was invented a few hundred years ago in the first place. That said, I find that notation is often abused in texts as a mere substitute for the normal human language which, while allowing to compress the text, does in fact nothin…

"does in fact nothing to help the reader better understand what is being said" For a mathematician it is the opposite, they just wish it would be written with symbols so that they could know precisely what the book is trying to say

We have symbolic expression in programming languages already.

It helps somewhat, but it isn’t a panacea.

We still have to comment our code and add context.

Re: Terry Tao on some desirable properties of mathematical notation

#100
post #91

Is it just me, or does probability theory in general have fairly terrible notation? Ambiguity between random variables and their distributions because of them simply being distinguished by being upper-case or lower-case, writing likelihood functions alternatively with an L() or p(), and using p() (with different arguments) to refer to different probability distributions. Perhaps I'm just having such a difficult time…

It is the difficulty of the theory in my experience.

I've had / have trouble and misconceptions many times, but when discussing with someone fluent in the notation and the field, 100% of the times things cleared up, and I couldn't think of a better notation to use.

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