More Descartes Accomplishments
On 19th June 1635, in Deventer, a maid , Hélène Jans, gave birth to an illegimiate daughter fathered by René (on the 15 of October) . The daughter's name was Francine. He passed her off as his "niece", and planned for her to be educated in France. However she died of scarlet fever on 7th September 1640. In 1637, he published "geometry", in which his combination of algebra and geometry created to analytical geometry, or better known as Cartesian geometry. René wanted his philosophy be taught at Jesuit colleges, and so in 1644 he made a textbook version of the arguments of the Discourse and Meditations, with more scientific material on the world, entitled Principia Philosophia (Principles of Philosophy). The Principles offered as a hypothesis that Earth is a "planet" and that the sun is a "fixed star". For the French translation in 1647 Descartes composed a letter in which he compared philosophy to a tree: metaphysics was the roots, physics was the trunk, and medicine, mechanics and morals were the branches. His efforts during Enlightenment and the scientific revolution shaped an era that would lay the foundations for modern western civilization. Rational thought to understand the universe, nature, and human relations was the basis of Descartes' work. It was the scientific method that came from the work of Descartes, Sir Isaac Newton, and Joseph Priestly.