ABSTRACT
Descartes holds that mind and body are two quite different sorts of substance; the mind is an immaterial substance. Descartes' theory of the material world had its weaknesses, and much of its detail was overthrown by Isaac Newton. For Descartes the essence of mind is consciousness. For Descartes there is no unconscious mental activity. Leibniz criticized Descartes on this point. He argued that to be aware of mental activity is itself a (further) mental activity, and so would require a further awareness of the awareness of the original mental activity and so on, ad infinitum. Descartes' account of the mind-body relation is satisfactory. But his Dualist theory makes it difficult for him to give a plausible account of interaction. The chapter examines Descartes' two arguments by which he tries to establish his mind-body theory. It look first at his argument from conceivability, and then at his argument from the indivisibility of the mind.
