it's true all hard sciences are born from unwavering faith in the Scientific Method (which has worked many, many times over). However, if you do believe in the ability of logic to explain all things, there are certain things you CAN prove absolutely. The existence of one's self, of time and absolute truth are both provable through simple logical statements (think Archimedes' Point and other logic satements). The existence of an external world is an extension of that basic logic, although it's subjectively perceived state does make absolute knowledge of just what's out there difficult at best.
But here's a wake up call: Math & Logic works, the Theory of Relativity works, what is known about Quantum Physics works. Don't believe me? Then please explain how you were able to post here
