^ There is a way that logic itself can logically be put into question
Descartes described this concept in his Meditations on First Philosophy
Basically (wikipedia summed it up nicely):
* If we cannot be certain that our senses do not deceive us, then we
cannot know anything with certainty.
* We cannot know whether or not our senses deceive us.
* Therefore, we cannot know anything with certainty about the world.
The "thought experiment" that demonstrates this is:
Suppose there was a daemon (spelled like that) which was all powerful and evil. It decides to fool you by controlling all of your perception. Even to what would appear to be basic logic. As in, you think 2+2=4 when really, 2+2=3, but the fact is that your mind and thinking are so controlled by the daemon that your logic is consistently wrong. The fact is, if such a daemon existed, then it would be impossible to disprove its existence, since we can no longer trust our own logic or thought process.
Therefore, all things that come from your mind are questionable and without any credence...
your own existence. This is because you are now thinking. You are wondering about your own existence. You think about a new idea - "Do I even exist?" However, you realize this one thing - thoughts need a thinker - therefore if you have thoughts, they originated from an existing thinker - you! How can we be sure that this is true? Because even if you are not human, not physical, and not detetable in some strange form of existence, the fact is that you think, and this points back to you, the thinker.
Interesting note- the first name of HIMSELF that GOD gave to man (to Moses as the voice from the burning bush) was I AM
http://en.wikipedia.org/wiki/Meditation ... Philosophy
P.S. Daemon is spelled that way becuase it is not only a "demon" but an inivisible background process. Also a term used in computing for a background process.