Descartes's philosophy has been the subject of intense study. Much is now known about its structure and content, about the details of his arguments and the spirit in which they were conceived and deployed and about the influences to which he was subject and the influence which he exercised upon his contemporaries and successors. There is, of course, no shortage of dispute about questions of detail and about overall interpretation. But the controversies are focused, and they are built on the considerable knowledge that has been gained through philosophical reflection and historical research. This book does not seek to engage systematically in that discussion, nor to provide a sustained examination of the whole of his main work, the Meditations on First Philosophy, let alone of the entire corpus of his writings. Its aim is more modest. It seeks to offer a unified reading of Descartes's metaphysics against the background of Scholastic philosophy.

Descartes moved within the world of Late Scholastic thinking. Even in his writings on natural science, where he was undoubtedly in profound disagreement with the Aristotelians, he constantly expressed awareness of this opposition. He saw himself as presenting a new philosophy, both natural and metaphysical, to take the place of Aristotle's and St Thomas Aquinas's. Since he wanted to take their place in the School, he was careful to avoid alienating the Scholastic establishment.