Page - 175 - in The Priority of Locomotion in Aristotle’s Physics

has consequences for the understanding of this argument, which raises at least two difficulties that one has to address. First of all, it is puzzling how the fact that the capacity of locomotion is posterior in the coming to be, i.e. prior in essence, is supposed to lead to the conclusion that locomotion has primacy over the other kinds of non- substantial change, as Aristotle infers a few lines later.22 Secondly, even if this is the case, the argument, as we have seen, is not about locomotion in general, but about a special kind of change in place, namely self-caused locomotion. But if the premises of the argument are only about this special way of locomotion and not about locomotion in gen- eral, then the argument cannot lead to a conclusion about locomotion in general. Aristotle is surely aware of this fact and does not intend to equivo- cate ‘locomotion’ in the special sense with its broader meaning. Most likely, he has good reasons to think that the priority of this capacity contributes something to showing the priority of locomotion in general. Apart from these two points that follow from the special use of the term ‘locomotion’ and that are about the structure of the argument, one may also have doubts about the second premise of the argument, namely that loco- motion is last in the process of coming to be of all beings undergoing this process. Aristotle seems to presuppose its truth and does not present any reasons for this assumption here. I will start by showing that Aristotle’s assumption is right, while an answer to the two remaining questions will be given later on. 7.1.4 Does locomotion come to things last? One reason why Aristotle presupposes the truth of the assumption that the capacity of locomotion comes last in the process of coming to be might be that he thinks this to be obvious from observation. An infant, for instance, is unable to walk around right after birth and it takes a while until it is able to perform its own locomotion. The same is true for other animals, like for instance dogs or cats. Other animals, however, precocial ones such as horses, are able to walk almost right after they are born. And certain kinds of fish—for instance the guppies23 in my fish tank—can swim around right after leaving their mother’s body. While this may not contradict the assumption that locomotion is rather late in the coming to be of animals, it nevertheless shows that the development of animals may differ from case to 22 ὥστ᾽ […] καὶ ἡ κίνησις αὕτη πρώτη τῶν ἄλλων ἄν εἴη κατ᾽ οὐσίαν, Phys. VIII 7, 261a13–20: “Therefore […] this [kind of] change would also have primacy over the other [kinds] in essence”. 23 Poecilia reticulata. Locomotion is prior in essence, since it is last in coming to be 175 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen