 In fact, Aristotle does not simply focus on the case of artefacts because their pre-existing matter is easier to identify. There is a particular issue here with the case of organisms, which arises out of Aristotle’s insistence that a human being, for instance, is composed of a rational soul, which is the form, and an organic body, which is the matter (for further discussion of this problem, see Ackrill 1972/73). It is characteristic of the matter of artefacts that numerically the same stuff which makes up one object can later be used as the matter of another: for instance, when one melts down a bronze statue, and then molds it into some jewelry, it is the same bit of bronze throughout. It is crucial that a thing’s matter can survive such changes, if it is to play the role that Aristotle needs it to play in cases of substantial generation and destruction, as being the thing that underlies such changes. If an artefact’s matter only contingently has the form it has, the same does not obviously seem true of organisms. Unlike in the case of a house built from bricks, it does not seem as though one’s body predates one’s existence, and so can serve as the underlying thing in a case of substantial generation. One might think that at least the body does exist after death, but in fact Aristotle would disagree. Instead, he insists that a dead body is only “homonymously” called a body—that it is only described as “a body” by extension, because it superficially resembles a living body (De Anima ii 1, 412b10–25; Metaphysics vii 10, 1035b9–25). It is not a real body, because it is incapable of performing the functions normally associated with bodies, just as a statue’s eye, or an eye in a painting, is not a real eye, because it is made of stone or paint, and thus cannot serve the function that genuine eyes exist for—seeing (for further discussion, see the supplement to the entry on Aristotle’s psychology on  a fundamental problem about hylomorphism).