More quotes by René 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."
"To live without philosophizing is in truth the same as keeping the eyes closed without attempting to open them."
"I think; therefore I am."
"The reading of all good books is like conversation with the finest men of past centuries."
"Common sense is the most widely shared commodity in the world, for every man is convinced that he is well supplied with it."