In an earlier paper in Theoria, I discussed an argument based on the idea of “soul-switching” that attempted to undermine the immaterialist account of human beings. The present paper deals with a parity argument against that argument in which the idea of “body-switching” plays a pivotal role. I call these two arguments, that have been reported by Razi (d. 1210), respectively “the soul-switching argument” and “the body-switching argument”. After some introductory remarks, section 2 of the paper describes the structure of (...) the latter argument. Section 3 considers some philosophical discussions in the ancient, modern, and contemporary eras in which the idea of body-switching (or some similar conception) plays a major role. In the following section 4, some criticisms of the argument are discussed and a general response that is meant to cover a broad range of objections is considered. This paper shows that the body-switching argument reported by Razi is a methodological antecedent of several contemporary arguments in defence of substance dualism. (shrink)