THE WORLD was one of the most ambitious treatises that René Descartes ever undertook; it was also brilliantly original, influential, and controversial. THE WORLD offered a new mechanistic theory of the entire universe, from the smallest particles to the stars and planets. Descartes argued that all bodies were just inert matter in motion, moved only by contact with other bodies, and nothing more. In one short treatise, Descartes dispensed with the natural philosophy of Aristotle and the universities. Yet, despite its brilliant originality, THE WORLD has largely been forgotten. This new translation restores the text as a key part of Descartes's legacy. It includes a helpful introduction, a summary of the translated text, a chronology, a recommended bibliography, and two translated excerpts of the sister treatise to THE WORLD, the TREATISE ON MAN.