Descartes, Rene (1596-1650), a French philosopher, who, from his influence upon later thought, has been called the father of modern philosophy. He was born at La Haye in Touraine, and was educated at the Jesuit college of La Fleche, where he displayed much talent. He entered the army, serving in Holland and Bavaria. In 1621 he left the army, and then after a period of travelling he settled in Holland, where he gave himself up to the study of philosophy. Finding the scholastic philosophy unsatisfactory in method and barren of results, he set about the discovery of truth. His first step was to divest himself of all preconceived ideas, and to take reason only as the test of truth. He concluded that the one proof of existence and the first established fact was consciousness of self. Hence his famous dictum, "Cogito ergo sum," which occurs in his Meditationes de Prima Philosophia. The soul, not the body, is the important part of man, not being limited by extension in space, but being free and immaterial. Not every perception of the soul is perfect, but this imperfect perception leads to and implies the idea of a perfect being, a supreme intelligence whence proceeds all knowledge of truth. The essential nature of the soul is thought, that of the body, extension. Animal bodies are automata, worked by "animal spirits," themselves material, located in the nerves and set in motion by the action of external objects. Descartes saved free-will by supposing that in man, the soul residing in the pineal gland could change the direction of these spirits. [Malebranche.] Descartes maintained the doctrine of innate ideas. In physics Descartes studied much, and his theory of "vortices," or violent but regular commotions of the ether which account for the movements of the planets, was widely prevalent until upset by Newton's theory of gravity. In mathematics he made valuable discoveries, and was the chief founder of the science of analytical geometry. He also developed the theory of equations. It is noticeable that he never broke with Catholicism. In 1647 he was granted a pension by the French Court, and in 1649 he was invited by Christina, Queen of Sweden, to Stockholm to give her instruction, but the rigour of the northern climate soon killed him.