Revised edition of the 1647 French translation of Descartes' "Principia philosophiae" by Claude Picot, a bon vivant known as "the Atheist Priest" with whom Descartes left his financial affairs in France. The "Principles of Philosophy" was the only complete version of Descartes's natural philosophy published in his lifetime and the first published work in which he presents and defends his vortex theory, the core of his heliocentric model of the universe.