I find Victor's response striking. Doesn't the knowledge of making such a very fundamental assumption effect(and perhaps undermine), in a very profound and troubling way, just about every philosophical, scientific, moral, political, mathematical etc etc etc thought and belief you've ever had? It's as if your entire corpus of knowledge and thought is hanging precariously by a single thread. In fact you can't even be sure there is a supporting thread at all, you might really be in free-fall. Wouldn't any further philosophy, maybe even life itself, become a charade, a game?David Quinn: How do you demonstrate that you're not an irrational human being with a warped understanding of formal logic?
Victor Danilchenko: You don't, you can't -- and you have no choice but to assume that that is not the case. it's a necessary presupposition, the assumption that you have apply syntactic transformations correctly. It's possible thatyou are insane and cannot do so, nor can perceive your insanity because it's consistent; but if you cannot perceive your insanity, then by definition you cannot perceive your insanity -- you cannot raitonally think your way out of it, because you lack rrational facilities. You have no choice but to assume your thinking sound on a certain fundamental level, just as you have no choice but to breathe.
I don't mean to misrepresent you Victor but what I've described does seem, to me, to be a possible and maybe even reasonable outcome of this fundamental assumption. I'd like to know what effects you think this assumption has and how you deal with this problem, assuming you see it as problem at all. I'd also like to hear other's views on this issue, especially David, Dan and Kevin's.