Discourse on the Method Discourse on the Method Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences () is a philosophical and autobiographical treatise published by René Descartes in 1637. It is best known as the source of the famous quotation ""Je pense, donc je suis"" (English: "I think, therefore I am", or "I am thinking, therefore I exist"), which occurs in Part IV of the work. The similar Latin statement, "Cogito, ergo sum", is found in "Meditations on First Philosophy" (1641) and "Principles of Philosophy" (1644). "Discourse on the Method" is one of the most influential
Cogito, ergo sum and let him deceive me as much as he can, he will never bring it about that I am nothing, so long as I think that I am something. So, after considering everything very thoroughly, I must finally conclude that the proposition, "I am, I exist," is necessarily true whenever it is put forward by me or conceived in my mind. (AT VII 25; CSM II 16–17) There are three important notes to keep in mind here. First, he claims only the certainty of "his own" existence from the first-person point of view — he has not proved the existence