Descartes, Rene du Perron(also Renatus Cartesius)

French mathematician and philosopher

founder of analytic geometry

wrote "Discourse on Method" 1637, "Meditationes de Prima Philosophia" 1641

sought to derive knowledge from indubitable 1st principle "I think, therefore I exist" (also "Cogito, ergo sum")

• "The greatest minds are capable of the greatest vices as well as of the greatest virtues."
• "Good sense is of all things in the world the most equally distributed, for everybody thinks he is so well supplied with it, that even those most difficult to please in all other matters never desire more of it than they already possess."
• "Each problem that I solved became a rule which served afterwards to solve other problems."
• "Cogito, ergo, sum. (I think; therefore I am.)"
• "Your joy is your sorrow unmasked. And the self-same well from which your laughter rises was often-times filled with your tears."