Des·cartes  (dā-kärt')  French mathematician, philosopher, and scientist who is considered the father of analytic geometry and the founder of modern rationalism. His main works, Meditations on First Philosophy (1641) and Principles of Philosophy (1644), include the famous dictum "I think, therefore I am." |
| Descartes (dā-kärt') Pronunciation Key
French mathematician and philosopher who discovered that the position of a point can be determined by coordinates, a discovery that laid the foundation for analytic geometry. |