Descartes, René

4to (196 x 147 mm). Woodcut printer’s device on title, 3 section-titles, woodcut initials, numerous woodcut text diagrams and illustrations, errata and licenses Kkk3.4; title-page lightly soiled with some minor marginal repairs and an inscription ("Collegii …") faded or effaced, light dampstaining at upper margin and fore-edge, first four gatherings with some soiling at top as well, a little scattered other foxing or soiling, tiny hole on i1 just touching two letters. Early vellum with overlapping fore-edges; ties lost. Cream buckram folding case, red morocco label. 

Dibner, Heralds of Science 81; Grolier/Horblit 24; Guibert, Bib. Descartes 1; Krivatsky 3114; Norman 621; Printing and the Mind of Man 129

FIRST EDITION OF A FUNDAMENTAL WORK FOR BOTH PHILOSOPHY AND SCIENTIFIC METHODOLOGY. Descarte’s first and most celebrated publication is the basis for his far-reaching influence as a philosopher and scientist. He makes three essential points in the Discours: “the truth of thought, when thought is true to itself (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. From these central propositions in logic, metaphysics and physics came the subsequent enquiries of Locke, Leibniz and Newton; from them stem all modern scientific and philosophic thought” (Printing and the Mind of Man).

The now famous Cartesian method is outlined in the Four Rules presented in Book II. Books III and IV contain discussions of metaphysics and physiology, the latter of which includes a reference to Harvey’s discovery of the circulation of blood. The appended essays on optics, meteorology, and geometry demonstrate the type of results that can be obtained by employing his rules of scientific investigation. His essay on optics contains important observations and experiments on refraction as well as one of the earliest mentions of Snell’s law of refraction. His brilliant treatise on geometry laid the foundation for analytic geometry.