Rationally proving rationality

[Magicthighs]

I'm having trouble understanding why you think it's possible to negate the argument that its intued by providing an explanation for how it is useful

But it's not intued, according to your definition of rationality. You say rationality means using your brain + input to come to a conclusion. That pretty much describes all experience.

"If I say that something is true simply because its true you cannot negate that statement by saying that its useful therefore its true"

This sentence makes no sense. I'm not replying to the posts about tautologies here, they are completely and utterly irrelevant to our mutual discussion.

"It simply doesn't work. The only way to rationally prove that rationality is a good way to look at the world is by tautology (as was stated earlier)."

And again, I disagree. What we have here is a category error. Rationality is a procedure, it just is, there's no truth value attached. It is one of the ways in which we make sense of reality. I'd love to see any [edit: recent] publications by any serious philosophers who claims mere rational thinking offers truths.

"From this then we have to ask how we prove tautology. The answer could be that it is intued to be true"

Or the answer could be "it's worked pretty fucking well so far".

"(in other words, the only way to prove that definition proves itself is to assume that that is evidence of proof.)
You make an assumption - intuition.

Uhuh. Using past experience is intuition. According to which definition, exactly?

You're claiming that inductive reasoning is intuition. You're asking a methodology which makes no absolute truth claims to make an absolute truth claim about itself, and then pretend that that's a profound thought.

Is that really all you've got?