Page - 83 - in The Priority of Locomotion in Aristotle’s Physics

A to B changes, and hence the claim that locomotion basically does not entail any change of the inner spatial order of the subject’s parts must be wrong. Yet, it seems that analysing what appears to be one locomotion into several locomotions might help us out of this impasse, for then, one might think, it will turn out that what was supposed to be a single locomotion from A to B actually consists of several locomotions, each of which taken by itself does not lead to a change in the inner spatial order of the subject’s parts. But, as I will now show, the same case that was made with respect to my walking from A to B may be made with respect to the subjects of the changes into which my walking can be analysed, so that a more precise ana- lysis of the change is no solution to the problem. It is certainly correct that one needs to be clear in specifying the subject of each specific kind of change in place. As we have seen, this means for my locomotion from A to B that what seems to be one change in place must in fact be considered as (at least) three different changes in place, namely those of my two legs and that of my whole body. But this does not solve the pro- blem, since the same argument that was made with respect to my locomo- tion from A to B, namely that it involves a change in the spatial order of my inner parts, may be made with respect to my right or left leg. For when I, as a human being that walks on two legs, change from place A to place B by walking, a change occurs not only in the relation between my legs and the other parts of the body, but also between the different parts of each leg: with respect to the left leg, for instance, the relation between the foot, the lower leg, and the thigh certainly changes. Granted, this might be solved by ana- lysing the motion of the leg itself into different changes, say into the change in place of my thigh, of the lower left leg, as well as that of the foot; after all, the reason why we have joints is that in the process of walking the relation of the different parts of the leg should change. But this analysis also fails to solve the problem, since with respect to at least one of these three subjects of change, namely the foot, the same case may be made again: in stepping on the ground my foot deforms in such a way that its inner spatial order also changes; with respect to the other two parts of the leg one could add that even in this case muscles contract and sinews are stretched so that the order of their inner spatial parts does change in some respect. Again, one might be tempted to think that this problem may be solved simply by divid- ing the subject into the actual subjects of different changes until one finally arrives at a number of subjects, in our example the parts of a human body, with respect to which one might rightly say that the inner spatial order of each of these subjects does not change in any way. This, however, will never be the case, since it would presuppose that the continuous whole of the body (or of any other subject) could be divided into parts which are not further divisible into parts that can change their spatial relation to each other. This, however, as is well known, is impossible for Aristotle, as it pre- What changes in quantity changes with respect to place 83 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen