Comment by ColinWright | Hacker News Reader

Comment by ColinWright | Hacker News Reader

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My PhD is in discrete math and graph theory, and yet I find calculus and probability to be indispensable tools. I devise algorithms that work on images and streams of text, and yet I use power series and vector spaces over the complex numbers to analyze them.

Writing code to implement error-correcting codes doesn't use continuous math, but some error-correcting codes are best understood as working in polynomial rings over finite fields, and many of the ideas and tools are directly linked to similar structures in infinite continuous spaces.

Limiting yourself to learning only about discrete math that does not require any continuous math is like limiting yourself to using only one style of programming, or one language, or one operating system, or one hardware platform. If you don't mind being so limited, fine. If you want to understand things in greater depth and thus give yourself more opportunities and have more tools in your arsenal, learn both.

They support each other in ways you can't imagine without actually learning them.

I am not saying connection does not exist (it certainly does), but I am saying connection is oversold. They support each other, but they don't support each other that much.

While I don't have PhD in math, I did learn calculus and probability. I am still not convinced that they should come before logic.

See, that's the thing. People who don't have all the tools to hand think that the connections are over-rated. People who do have more of the tools to hand think that it's much more important than is realized by people who don't have all the tools to hand.

It's the blub[0] paradox all over again. I would suggest that you haven't (yet) learned enough to realize that the connections are much deeper, stronger, and important than you realize.

It may well be that you don't need to know that the derivative of 3x^2 is 6x, but the influence on working with discrete math of a deeper understanding of continuous math is real, but subtle and hard to explain. Like Spock said when McCoy asked what it was like to be dead:

    McCoy: Come on Spock this is me, McCoy!! You really
           have been where no one has been before, can't
           you tell me what it felt like?

    Spock: It would be impossible to discuss the subject
           without a common frame of reference.

    McCoy: You're joking - you mean I have to die before
           we can discuss your insight on death?

We can't all learn everything. I'm not advocating that everyone should get a PhD in cross-disciplinary math subjects, just as I'm not advocating that everyone should become fluent in Japanese, Russian, and Finnish, or that everyone should become fluent in Scheme, Haskell, and Erlang. What I am saying is that I, who do have a PhD in math, believe that the connections are more extensive and useful than you realize.

[0] http://www.paulgraham.com/avg.html

The connections may be more extensive than the average software developer will ever see. But does that make them useful? How can unrecognized connections be useful? And if those connections are not useful without the higher education he/she will not receive, then what was the point in learning them?

If you'll never program in Lisp or Haskell, is there any value in learning them? Those who do learn them say yes, that doing so has changed for the better the way they think.

Similarly other subjects in math that do not, on the surface, seem to be relevant.

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