René Descartes was born in La Haye, Touraine, France in 1596. He was educated at the Jesuit school of La Flèche, where he studied literature, philosophy, and mathematics. After graduating from La Flèche, Descartes attended the University of Poitiers, studying law and graduating in 1616. He briefly pursued a military career before turning to the study of philosophy and science.
Descartes is considered to be one of the most important philosophers in Western civilization. His most important contribution was the application of the rational, inductive methods of science to philosophical questions. Using this method, Descartes attempted to derive an entire epistemology from the first principle Cogito ergo sum (I think, therefore I am
).
In science, Descartes studied astronomy, physics, physiology, and optics. Many of his conclusions were wrong, but they are nonetheless important because they were based on rational, mechanical explanations.
In mathematics, Descartes greatest contribution was establishing the fundamental connections between geometry and algebra. He studied curves in terms of the equations that produce them, used letters to denote unknown quantities, and invented the superscript notation for powers. Descartes famous rule of signs is a method for counting the number of positive and negative roots of a polynomial equation.
Descartes major works include Essais Philosophiques (Philosophical Essays), published in 1637, Meditationes de Prima Philosophia (Meditations on First Philosophy), published in 1642, Principia Philosophiae (The Principles of Philosophy), published in 1644.
Descartes died of pneumonia in 1650.