1596-1650

French mathematician and philosopher whose most significant contribution was analytic geometry. His coordinate system—subsequently called Cartesian in his honor—allowed geometric problems to be solved algebraically and thus paved the way for Isaac Newton's development of the calculus. With his new tools Descartes made the first systematic classification of curves. His vortex theory—according to which Earth is carried around the Sun in a vortex—held sway for over a hundred years on the European Continent and delayed acceptance of Newton's work in France.