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Comment by TEP_Kim_Il_Sung | Hacker News Reader

Didn't Gödel prove that you can't prove a theory with its' own ruleset?

In physics maths always go haywire durnig phase changes, as gas laws don't apply to liquids, and such.

No, he proved that under existing axiomatic systems, there are some statements which cannot be proven to be true axiomatically, even though they are true; such axiomatic systems are, in his terminology, incomplete. A subtle but important difference.

One thing I've always wondered is if there's any _interesting_ statements that can't be proved or if they're all kind of self-referential nonsense statements.

There's whole _fields_ of inquiry that either take or leave the axiom of choice; so yes, absolutely.

Is that the kind of statement Godel was talking about? Seems to me to be somehow different. It's not really true or false, it's an arbitrary choice, so it's just something you either decide is part of your system or not, not a true statement that's unprovable.

Maybe I'm missing something?

Axiom of choice isn't really relevant to Godel's work, except for the fact that it's part of axiomatic systems. But in response to your comment, I was pointing out that there's lots of interesting math that comes from the results of his work; namely under different axiomatic systems you can find different and interesting results.

Axioms are, by definition, a choice.

On the one hand, I've often understood that it would be nice if we could assemble a list of "all the axioms" and prove it's consistent - at least that's how it was presented to me and roughly my interpretation of what eg. Russell and Whitehead were trying to do before being derailed by Godel proving it's impossible. On more recent reflection, it seems a little silly to want a proof in system X of the consistency of system X, even before we get to Godel, because if system X is inconsistent then it can definitely provide a proof that it is consistent by the principle of explosion.

A while ago there was a result that relates to materials science: https://arxiv.org/abs/1502.04135

What a paper!

Sure there are, just choose your axioms that are interesting…

also, that his proof exists within an axiomatic system but IS ONE of its provable statements, is wildly crazy genius weird 'serendipitous' math...?! shows that at least for the boundary beyond the provably meaningful, we can still 'talk' about or 'point' at the unknown and say things like 'hey, over there is something we cannot really know nor talk about

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