French philosopher and mathematician Rene Descartes is behind many important concepts, from the Cartesian plane in mathematics to the "I think, therefore I am" philosophy. Descartes was born to humble beginnings, but he managed to become an important thinker and notable person.
Young Rene Descartes began his education at age 8 by entering a Jesuit College, where he learned classics, logic and the philosophy of Aristotle. Despite receiving a religious education, he believed in the Enlightenment ideal of separating intellectual pursuits from religion.
Though intelligent, his health was poor, and young Rene was allowed to stay in bed until 11 in the morning, something that he continued throughout his life.
He ended up joining the Dutch military after earning his degree in law, and it was during his military service that Descartes began having original philosophical and mathematical thoughts while dreaming. In fact, these dreams all occurred on the same night, November 19, 1619, and he considered this a watershed moment in his life.