  Although Aristotle also discusses efficient and final causes, he falls short of a true understanding of creative causality because he abandons the hypothesis of the Forms. Without the transcendent Forms, there can be no explanation of the being of things, only an explanation of their movement and change. Given Aristotle’s narrow understanding of nature, it must come as no surprise, Proclus notices, that he admits of cases of ‘spontaneous generation’ in the sublunary realm, which again restricts the purport of efficient causality. Moreover, because of his rejection of the demiurge (and of the One), Aristotle is also forced to limit efficient causality to the sublunary realm. In fact, in his view there is no cause of existence of the celestial bodies or of the sensible world as a whole: they exist necessarily in all eternity. But, as Proclus argues, such a position will force him to admit that the world has the capacity to constitute itself, which is absurd (see below).