 One might try to reject the first premise of the argument, on the grounds that a person’s matter is essential to them. We have seen that Aristotle plausibly does believe this about a person’s proximate matter—their body—since a dead body is only homonymously a “body”. Nevertheless, he is committed to their more remote matter—the elements that make them up, for instance—being capable of existing independently of them. He needs there to be something to underlie the change whereby a substance comes into or goes out of existence, to make it consistent with his account of change in general in Physics i 7. There seems to be no reason to deny that, when a tree, for instance, dies, the earth, air, fire and water that constituted it still exist in the dead stump. But, if so, there seems no reason to think they could not leave the stump, and end up becoming the matter of some new tree. This is all that is needed for the problem to arise. Prime matter, if it exists, will not help: if the elements are allowed to escape the substances that they underlie, it seems that the prime matter that underlies them should also be capable of doing so. It is supposed to be capable of underlying anything; so insisting that it is confined to being the prime matter of a particular sort of thing makes no sense.