I remember reading Descartes in engineering school, wasn't crazy about him then. But I found a great online source for all classic books and have been reading some of them again.
I think, therefore I am is an awesome concept. I think the myth of the Matrix can be debunked by this one principle of philosophy.
I thence concluded that I was a substance whose whole essence or nature consists only in thinking, and which, that it may exist, has need of no place, nor is dependent on any material thing; so that “I,” that is to say, the mind by which I am what I am, is wholly distinct from the body, and is even more easily known that the latter, and is such, that although the latter were not, it would still continue to be all that it is.
After this I inquired in general into what is essential to the truth and certainty of a proposition; for since I had discovered one which I knew to be true, I thought that I must likewise be able to discover the ground of this certitude. And as I observed that in the words I think, hence I am, there is nothing at all which gives me assurance of their truth beyond this, that I see very clearly that in order to think it is necessary to exist, I concluded that I might take, as a general rule, the principle, that all the things which we very clearly and distinctly conceive are true, only observing, however, that there is some difficulty in rightly determining the objects which we distinctly conceive.
