Discourse on the Method
Despite frequent moves, he wrote all of his major work during his 20-plus years in the Netherlands, initiating a revolution in mathematics and philosophy. In 1633, Galileo was condemned by the Italian Inquisition, and Descartes abandoned plans to publish "Treatise on the World", his work of the previous four years. Nevertheless, in 1637, he published parts of this work in three essays: "Les Météores" (The Meteors), "La Dioptrique" (Dioptrics) and "La Géométrie" ("Geometry"), preceded by an introduction, his famous "Discours de la méthode" ("Discourse on the Method"). In it, Descartes lays out four rules of thought, meant to ensure that our knowledge rests upon a firm foundation: