Page - 206 - in The Priority of Locomotion in Aristotle’s Physics

emphasize that these changes do not happen solely in virtue of the subject’s suddenly being at some other place, but because of what is at the respective place. The fact that the place where the goldfish landed is full of air instead of water, or that the place I went into is full of fire, is an accidental feature of the change in place. Suppose I know that goldfishes tend to jump out of their fish tanks and for that reason put a second one next to the one in which my goldfish lives so that it would not land on the table, but in the other fish tank instead. That is to say, by jumping out of the water it would not move to a place full of air, but to one full of water, and therefore would survive, although the place to which it moves and the locomotion that takes it there in both cases are more or less identical. The same is true for the house in which I burned to death in the other example: if I had entered the house and walked to exactly the same place at a time when it was not burn- ing, I would not have died. Thus, in undergoing locomotion x is not departing from its essence merely in virtue of changing with respect to its place, and for this reason locomotion cannot result in x’s corruption merely in virtue of changing x with respect to its place. This understanding in a sense seems once again to be supported by a passage from Top. VI 6. There it is stated that substances do not differ merely by being at different places.84 Accordingly, one cannot say that the change of place makes a substance change with respect to its essence; x’s place is irrelevant to what kind of being it is. Or, as Aristotle puts it, a land animal will still be a land animal even if it is in the water.85 In the same way, I remain a human being, no matter where I go. Therefore, what undergoes locomotion as a whole in no way departs from its essence, while that which changes in quality or quantity does so. Hence, Aristotle is right to claim in sentence (1) of the relevant passage from Physics VIII 7 that the subject of locomotion departs from its essence the least, although the reasons for this assertion are not explicitly stated in the text. That coming to be and corruption involve a change in essence is obvious from their definition as substantial changes. Yet, contrary to what one might have expected, it has become clear that change in quality or in quantity, in contrast to change in place, in a certain sense may make its respective subject step out of its essence. This is another reason why loco- motion has a special status among the four kinds of change and, as I will now show, is correctly called primary in essence. 84 οὐ δοκεῖ γὰρ διαφέρειν οὐσία οὐσίας τῷ ποὺ εἶναι. Top. VI 6, 144b32: “For it seems that locality cannot differentiate between one substance and another.” (Transl. Pick- ard-Cambridge). 85 See Top. VI 6, 144b37–145a1. 206 Locomotion is prior in essence ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen