Discourse on the Method of Reasoning

The Discourse on the Method is a philosophical and autobiographical treatise published by Ren Descartes in 1637. Its full name is Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences. The Discourse on The Method is best known as the source of the famous quotation "Je pense, donc je suis" ("I think, therefore I am")