TH The Modern PHILOSOPHY SERIES HE Modern Student's Library has been enlarged to include a series of volumes containing writings of the great philosophers. These volumes are edited by the most competent authorities at home and abroad. The selections are comprehensive and suited to the special needs of students and the general reading public. Each volume contains an introduction giving a brief outline of the system of the author and indicating his place in the history of thought. The Philosophy Series is under the general editorship of Ralph Barton Perry, Professor of Philosophy, Harvard University. [For a complete list of THE MODERN STUDENT'S LIBRARY see the pages following the text] CHARLES SCRIBNER'S SONS 2-24-4245 2-21-112 45708 240p, INTRODUCTION I The René Descartes, more than any other figure in the seventeenth century, marks the intellectual transition from the Middle Ages to the modern world. He stands where the streams of European thought meet. current of medievalism flows into his philosophy and runs strongly through his metaphysics and theology, but the stream of modernism, the current of mechanical science that has borne along the European mind into the twentieth century, flows from his philosophy. In his attitude toward the Church and the mysteries of the Christian religion, Descartes might have been a good Catholic of the twelfth century. Here the spirit of Duns Scotus, St. Anselm, and St. Augustine is still alive. In his views of the physical world and the scientific method, he breaks sharply with the Middle Ages; he brings together in a complete system the leading ideas of the century of scientific discovery which produced Galileo, Bacon, Hobbes, Leibniz, Spinoza, Huygens, Harvey, Locke, Boyle, Newton. Not that Descartes was a scientist to be ranked beside Galileo or Newton. Only one of his achievements in exact science remains of value to-day, his geometrical method, now known as analytical geometry. He lacked the patience in observation, the love of fact for its own sake, which enables the scientist to build carefully, brick on brick, a solid structure of detailed knowledge. Like Aristotle, he was enamored of the a priori. He |