This is the second of a new two-volume edition of the works of Descartes in Penguin Classics. This volume is designed for students who approach Descartes from the point of view of his philosophy of science. It includes "Discourse on Method", the most accessible and well-known of his discussions of scientific method; the first seven chapters of the earlier, unpublished work, "The World"; as well as a selection of Descartes' correspondence and his replies to his critics.