René Descartes, du Perron (Latin: Cartesius Renatus), philosopher, mathematician and scientist, was born in La Haye near Tours Touraine (France) on 31 March, 1596. He came from an ancient noble family in France. At the age of eight he entered the Jesuite College at La Flèche. After graduation he studied law at the University of Poitiers. From 1619 to 1620 Descartes worked for Duke Maximilian of Bavaria. In 1625 Descartes he settled in Paris with a comfortable inheritance. His work "Rules for the Direction of the Mind" earned him a very good reputation. In 1637 Descartes published his arguably most important popular scientific work "Discourse on Method". "Meditations on First Philosophy" appeared in 1641, "Principles of Philosophy" followed in 1844. René Descartes was invited to Sweden in 1649 by his longtime pen-friend Queen Christina of Sweden. René Descartes died in early 1650 due to pneumonia. However, there are theories that René Descartes may have been poisoned using Arsenic.