Rene Descartes - Discourse on Method

Good sense is, of all things among men, the most equally distributed: for every one thinks himself so abundantly provided with it, that those even who are the most difficult to satisfy in everything else, do not usually desire a larger measure of this quality than they already possess.
Rene Descartes
I know not if I was then a man dreaming I was a butterfly, or if I am now a butterfly dreaming I am a man.
Rene Descartes
If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.
Rene Descartes
Each problem that I solved became a rule which served afterwards to solve other problems.
Rene Descartes
The reading of all good books is indeed like a conversation with the noblest men of past centuries who were the authors of them, nay a carefully studied conversation, in which they reveal to us none but the best of their thoughts.
Rene Descartes
I think; therefore I am.
Rene Descartes
In order to improve the mind, we ought less to learn, than to contemplate.
Rene Descartes
If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.
Rene Descartes
Cogito ergo sum. (I think; therefore I am.)
Rene Descartes
Except our own thoughts, there is nothing absolutely in our power.

- Rene Descartes - Discourse on Method