Quote by Descartes, René

"I think, therefore I am."

"The greatest minds are capable of the greatest vices as well as of the greatest virtues."

"Doubt is the key to knowledge."

"If you would be a real seeker of truth, it is necessary that at least once in your life you doubt, as far as possible, all things."

"Life is meant to be lived with passion."

"Life is what happens when you're busy making other plans."

"Life is a journey, not a destination."

"Life's too short for regrets."