Aristotle on Metaphysics(2004) - Bibotu.com

THE ULTIMATE CAUSE OF CHANGE: GOD 277of searching for explanations—reasons, causes. Still, we may ask how theprinciple of sufficient reason applies to the change of the outermost heaven,the limit of nature. Why, we may object, is not change and motion innature as a whole something basic and primitive which does not requirefurther explanation? The principle that every event has a cause will stillapply within nature, but it does not, the objection claims, apply to natureas a whole. But this objection does not really touch <strong>Aristotle</strong>. For what theultimate cause of change is supposed to explain is not simply motion andchange in general, but a specific change of a particular thing, namely, theperfectly uniform, circular motion of the outermost heaven. And this isevidently one particular event, even if a maximally cosmic one, whichcontrasts with any other event within nature, such as the growing of thegrass in the garden. So the principle of sufficient reason that says that everyevent has a cause will apply to the motion and the change of the outermostheaven just as much as to any other event within nature.One may still object that the motion of the outermost heaven does notitself require an explanation, for the simple reason that it is maximallycosmic and coincides with the limits of nature. But <strong>Aristotle</strong> offers a basicreason for thinking that this particular change, the change of theoutermost heaven, does itself require an explanation. The reason is thatthis change, like any other particular change, is contingent, i.e. it couldhave been different from what it in fact is:If something changes, it could have been different [from what it infact is]; hence the first motion in space [i.e. the motion of the firstheaven], even if it is in a state of actuality [since it always moves inthe same way], still, in so far as it changes, to that extent it couldhave been different [from what it in fact is], i.e. different in respect ofplace even if not in respect of its existence.(1072 b 4–7)The point is that the outermost heaven, whether or not we think that itcould not have existed, could have moved in a different way from how itactually moves. So we need an explanation of why it moves in the way itdoes.Here it emerges quite clearly that <strong>Aristotle</strong> is working with a very strongversion of the principle of sufficient reason: if something could, in aparticular respect, have been different from what it in fact is, then anexplanation is needed of why it is as it is, and not different, in this respect.That he is working with this principle of sufficient reason is confirmedwhen he goes on to say that the ultimate cause of change, on the other hand,