Cartesian Physics
Chapter 2 argues that Descartes’ physics is compatible with the Thomistic theory of divine concurrence. Descartes holds that God preserves bodies in existence, continually recreating them in different positions over time. Section 2.1 argues that it follows that (on Descartes’ view) God causes all the motions that occur in the world. Some of Descartes’ interpreters take Descartes’ physics to imply that mere bodies do not have any motive force or power, that is, any ability either to move themselves, or to cause motion in other bodies. Descartes’ physics thus seems to imply body–body occasionalism. Yet sections 2.2 and 2.3 show that Descartes is not committed to this conclusion. Instead, section 2.3 argues that Descartes thinks that bodies are “secondary causes” of motion that have active causal powers. Section 2.4 shows how this concurrentist reading of Descartes’ physics is consistent with his conception of body as extended substance.