Page - 60 - in The Priority of Locomotion in Aristotle’s Physics

one think that Aristotle in this first argument is trying to establish that loco- motion is primary specifically with respect to all changes that occur in liv- ing beings and accordingly focuses here on discussing the special case of organic change in quantity. According to the De Anima a plant’s soul has the nutritive capacity that, among other things, is responsible for the plant’s growth.57 It is the nature of a plant to have such a source of its own growth within itself. And indeed it is a fact that we see plants growing, i.e. changing in magnitude. Yet a plant, does not have the capacity for locomotion, i.e. cannot move from point A to point B of its own accord.58 But if the plant is not even capable of causing a change in place, one might wonder in what way locomotion should be presupposed by and in this sense prior to the growth of the plant. The same case can be made for other living beings beside plants that do not have the capacity to move themselves from point A to point B, such as for example animals like sponges. But in order to show that locomotion is pri- mary in general among the different kinds of change, Aristotle needs to make clear that it is primary in the important case of changes that have their source in living beings. For, as we have seen, it seems that they are responsible for all changes in the sublunary sphere apart from those, of course, which have their source in superlunary causes. Accordingly, one might think that Aristotle by means of the first argument is attempting to show that change in place is primary in all living beings, although one could rightly object that some living beings do not even have the capacity to cause locomotion. If Aristotle is successful in rejecting what seems to be an objec- tion, then it appears that, with respect to all changes caused by such sources, locomotion must nonetheless be prior to them. Yet, there is a problem with thinking that this is what Aristotle intends to show by means of the first argument. The reason, as I will now show, is that although non-locomotive living beings have a nature, they strictly speaking cannot be considered self-movers. This becomes clear in the third of the three possible objections against the claim that change must always exist, objections that are stated in Phys. VIII 2 and that I have already mentioned in a previous chapter.59 In this objection—let us call it the third eternity- objection—Aristotle raises a problem that, as we will see, is related to the point in question in different respects and will help us to better understand Aristotle’s motivation for focusing on cases of growth in living beings. The objection makes use of the fact that animals as self-movers can be observed to move suddenly from one place to another, although previously in a state 57 See for instance de An. II 2, 413a25–b1. 58 See de An. II 2, 413a31–b1. 59 See section 2.4.3. 60 Change in quality and quantity of living beings ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen