Rene Descartes was a French philosopher, mathematician, and scientist born on March 31, 1596. He is often referred to as the father of modern philosophy due to his influential ideas about skepticism and the nature of existence. His famous statement, "Cogito, ergo sum" (I think, therefore I am), emphasizes the importance of doubt and reasoning in understanding reality. In addition to his philosophical contributions, Descartes made significant advancements in mathematics, particularly in developing Cartesian coordinates. This system laid the groundwork for analytical geometry, linking algebra and geometry. His work has had a lasting impact on various fields, including philosophy, mathematics, and science.