To answer the question of whether the mind is a physical thing requires us first to understand what is meant by "physical" and "thing". The traditional debate over the mind-body problem tends to take it for granted that these terms should be understood in the way they have been since the 17th century: those who these days assert the doctrine of physicalism or materialism take themselves to be disagreeing, for example, with Descartes. I argue that unless we accept the metaphysical assumptions behind this 17th century debate, the contemporary debate between dualists and physicalists/materialists loses a lot of its point; and that once we explicitly abandon these assumptions, we can see the way to the conclusion that there is no interesting sense in which the mind a physical thing.