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."

"A good man treats his wife with respect."

"Kindness always comes back around."

"The power of a smile can change everything."

"Kindness is weakness to some. Not to me."