Abstract

This article is concerned with three exceptional episodes in Descartes's life, each of which had a profound impact on the development of his thought; several arguments are advanced and new primary material uncovered to support our contentions. First, he did indeed visit Prague in November 1620 and his experiences there shaped his later views of mechanical automata, optical illusions, and the pseudosciences. Second, his encounter with the mysterious Sieur de Chandoux (identified here for the first time) in November 1628 shows that Chandoux was not a reformer or a skeptic but a disguised cynic or erudite libertine. Third, he had close family connections with, and an informed report about, the demonic possessions of Loudun (near Poitiers) in 1634-36, and these shaped his version of the evil demon argument in the _Meditations. Through this argument and his 'new way of ideas' Descartes overthrew traditional notions about soul and mind, the status of the subject, and the evidence for truth. This permitted an understanding of the manner in which one can be an other for oneself and the manner in which certainty can be grounded with the 'objective' structures of consciousness