> You don't "prove" theories. That's not allowed for in the scientific
> method.

Correct. The word "proof", after all, originally meant "test", as in "degrees proof" of alcohol, and the true meaning of "proof of the pudding", and of "the exception proves the rule".

As it happens, I've just been re-reading Simon Singh's Fermat's Last Theorem, in which he points out that the scientific theory is the poor relation of the mathematical theorem. The latter is absolute (admittedly the underlying axioms are accepted as true).* The same is true for proofs.

* Shut up at the back there, Gödel.