Page - 201 - in The Priority of Locomotion in Aristotle’s Physics

As we have seen, change in quality and quantity both are able to play a crucial role in substantial changes, although they are non-substantial kinds of change. For the discussion of the second argument for locomotion’s priority in essence it seems to be of special importance that change in qual- ity and quantity can serve as essential contributors to their subject’s corrup- tion. For it appears that in this way, i.e. in virtue of being such an indispen- sable part of the corruption process, both kinds of change may be said to make their subject depart from its essence. This, however, does not suffice for establishing what Aristotle claimed, namely that locomotion has essen- tial priority, because what is undergoing locomotion departs from its essence the least. One still needs to show that locomotion does not make its subject step out of its essence, or at least does so less than the other two non-substantial kinds of change. 7.2.4.3 Locomotion as a part of a change in essence? The reason presented for locomotion’s being less involved in change in essence was that of the different kinds of change locomotion alone does not change the being of its subject in any way.75 None of what I called ‘intrinsic attributes’ of the subject x of a locomotion changes merely because x changes its place. But this is what happens in every change in quality or quantity, which is the reason why these kinds of change, in a way, can at least contribute to their subject’s change in essence by being a part of this substantial change. A change in essence is a change that always occurs in that which is undergoing this change. Corruption, therefore, is a change in that which is ceasing to be. Since locomotion does not affect its subject’s inner attributes, one accordingly may say that it cannot be a part of a change in essence in the way alteration and change in quantity can. This is in perfect accordance with parts of the results of my discussion of the sec- ond argument for locomotion’s priority. For in this discussion I showed that locomotion per se does not entail a change of the inner spatial order of its subject x’s parts, and hence, that x, apart from the change in place it undergoes as whole, is not changed in any way whatsoever, or, to put it in other words, x is left completely untouched with respect to its being.76 This fact, as I showed, follows from locomotion’s ontological priority, because, as I made clear in my discussion of the second argument as well, change in place is an inelimnable part of any other kind of change insofar as any change undergone by x in quality, quantity, or substance necessarily 75 See Phys. VIII 7, 261a21–23; on this see 7.2.2. 76 See chapter 4, esp. section 4.2.3. Locomotion alone preserves its subject’s essence 201 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen