Descartes (René) Discours de la Methode, first edition, woodcut device on title, numerous woodcut illustrations and diagrams in text, foxed and browned, contemporary vellum, [Dibner, Heralds of Science, 81; Grolier/Horblit 24; Guibert, Bib.Descartes, 1; Norman 621; Krivatsky 3114; PMM 129], 4to, Leiden, Jan Maire, 1637.

⁂ The cornerstone of 17^th century philosophy and science. 'Descartes's purpose is to find the simple indestructible proposition which gives to the universe and thought their order and system. Three points are made: the truth of thought, when thought is true to itself (thus, cogito, ergo sum), the inevitable elevation of its partial state in our finite consciousness to its full state in the infinite existence of God, and the ultimate reduction of the material universe to extension and local movement' (PMM).