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Comment by h0l0cube | Hacker News Reader

As per the article, you don't need a math PhD to code it either:

> TA I think I think the math PhD itself didn't because I'm not in like n dimensional non Euclidean space. It's tricky. But But I think having practiced a lot of math and just solved a lot of problems. And generally being good at math. Like I've taught linear algebra. So that part of games is not hard for me, right? It's like and same thing like I'm calculus comes up sometimes. I've used a partial differential equation once it was for like windspeed firing arrows. I don't remember what it was. It was something like that. But it didn't I didn't really end up needing it. I mean, I used it to inform what I was doing but in the end faster just to use discrete simulation and miss a little bit. It's fine to miss. [Tarn laughs]

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Ha I was going to quote this exact passage. The "and miss a little bit. It's fine to miss" was oddly satisfying to read.

> because I'm not in like n dimensional non Euclidean space

huh. I was sure that DF used taxicab distances

Taxicab distances are perfectly fine in Euclidean spaces

Many things go by the name of “Euclidean space” (basically the “flat” case of every kind of space, linear=vector, affine, topological, uniform, metric, topological manifold, algebraic variety, differential manifold, Riemannian, topological linear=vector, Banach manifold, countless others).

I (and probably the GP) think of “R^n with taxicab distance” as a metric space, which is indeed non-isometric to the “Euclidean metric space” as in “R^n with Euclidean distance”, thus can meaningfully be called non-Euclidean in this context.

You seem to be thinking of whether taxicab distance agrees with some preexisting, weaker structure on this structure’s notion of “Euclidean space”, like how the taxicab metric topology agrees with the topology of the “Euclidean topological space”, that is, “R^n with standard topology”, or how taxicab distance is translation-invariant thus an admissible norm on the “Euclidean vector space”, that is, “R^n with standard R-vector space structure”. In those senses taxicab distances are in fact fine in Euclidean spaces. (Note that this ceases to work as soon as you go into infinite dimensions, probably in any of the many, many ways to do so.)

I think we're just working with slightly different definitions of "works fine". Isometry is a pretty strong definition of "works fine", but R^n with 1-norm is isomorphic and quasi-isometric to R^n with 2-norm which is still fairly strong.

didn't need language classes either is it? Not that my commenting is free of errors anyway

This is an imperfect transcript of (casual) conversation.

It's a transcript; you don't type like you talk either. I know I uh and ahh a lot more, awkward pauses, etc.

But you do need a math PhD to code it, because if you were coding it, you'd be Tarn Adams, who has a math PhD. There is no state in which one can be "coding Dwarf Fortress" and "not have a math PhD".

I'd posit that there could exist an alternate universe where someone without a math PhD made exactly Dwarf Fortress

Well if such a universe exists, there is probably one where it turns out exactly the same w/o math PhD, and another where its a very different game. In any case, we're not privy to those universe's goings on :/

To that I'd say if you had a jazillion monkeys with a jazillion typewriters, the monkey that types Dwarf Fortress has at most at 50% chance of having a PhD

That universe exists and the game is called Rimworld!

I thought it was discworld

Turtles all the way down

I would make an even stronger assertion that this is almost certainly the case. ;-)

Classic theoretical mathematician answer, but games are applied mathematics :P

The most reasonable gloss on "You need a math PHD to code Dwarf Fortress" is "Necessarily, if someone codes Dwarf Fortress, they have a math PhD." The modality "necessarily" is widely understood to refer to possible alternative states of affairs, not merely those states of affairs which are actual. In other words, if an alternative state of affairs is possible, in which someone (whether Tarn Adams or someone else) codes Dwarf Fortress without a math PhD, then it is not true that it is necessary to have a math PhD to code Dwarf Fortress.

Most people in this thread believe that since a math PhD did not play a crucial role in Adams's ability to develop Dwarf Fortress, then it is true that such an alternative state of affairs is possible. (The language of "alternative universes" - usually called possible worlds in the literature - is one way of getting at this.)

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