This is conceptually incorrect regarding a mathematical "theory". "Proving" a mathematical theory simply establishes that it is consistent with the assumptions of the established framework of discussion; it says nothing about whether or not it is true in any sense of the word.
It doesn't even establish that with certainty. Several famous examples exist. The four-color theorem was proved for a while, and then went back to being unproved. "Principia Mathematica" was accepted for about 50 years before an industrious grad student found a flaw in the proof.
Anything humans, being fallable finite entities, have to turn a crank on to produce results, such as proofs in formal systems, is subject to recall.
In any sense of the word? Not even the sense of the word in which "true" is taken to mean "consistent with the assumptions of the established framework of discussion"?
Of course, by this standard, your post is not "true", since you've contradicted yourself. ;-P
I know, I know, you're going to get back to me (as Physicist did) with your detailed intricate view of how I should be defining "true" and "right". And I suppose that under your appropriately bizarre definition of "true", I won't be allowed to say that the Mean Value Theorem (or, for that matter, "2+2=4") is "true", for some reason.
You know what? I'm not interested. I think you know what I am saying, and know that what I am saying is unobjectionable, but you would just like to be a nuisance and/or show off.
Save it.