Page - 55 - in The Priority of Locomotion in Aristotle’s Physics

spring, for instance, when the snow is melting, rivers usually become broader and in this sense increase in size. For once the snow starts to melt, additional water may flow into the rivers, making them become larger. Yet, as in the case of the enlargement of the puddle, the water which flows into the river does not have to undergo any sort of alteration in order to become a part of the river.40 As a last example of an increase in quantity that does not involve an alteration of that which is added, one could also refer to the case of blowing up a balloon: the more air I blow into the balloon, the more its size will increase. Yet, the air which I blow into the balloon does not have to alter in order to become a part of the air in the balloon. More examples like this could be added. Accordingly, I think it is correct that Aristotle in the first argument understands change in magnitude, i.e. growth and diminution, as the kind of change in size that living things undergo. However, this seems not only true for this passage, but for many others as well. As I see it, Aristotle in general considers change in quantity not merely as some process involving increase and decrease in size, but primarily as such cases in which a living organism grows and diminishes. For, besides the fact that it is clearly stated in the De Anima that only things that have a soul, i.e. living things, can be subject to growth and diminution, that is, change in quantity, in the proper sense, this is also what is implied by the way in which growth and diminu- tion are described in Phys. V 2 and VI 10. For in the first of these two pas- sages change with respect to quantity (κατὰ τὸ ποσόν) is defined as growth, i.e. change “to the complete magnitude” (εἰς τὸ τέλειον μέγεθος αὔξησις), and as diminution, i.e. change away from this magnitude (ἐκ τούτου φθίσις).41 In Phys. VI 10 something more is added, for here it is stated that growth aims at reaching the complete magnitude that is specific to the nature (φύσις) of the respective thing, while diminution is a change away from this magnitude.42 Both passages clearly indicate that change in quantity for Aristotle is not merely becoming larger or smaller in some sense, but rather needs to be understood primarily as a change with respect to a certain goal and nature. Yet, one certainly cannot say that whatever 40 The melting of the snow, of course, involves an alteration, namely the heating of a por- tion of snow, yet, when what was formerly snow and now is water flows into the river, the portion of water does not have to change in quality; it does not matter whether the increase in size occurs by the water from molten snow, or by rain, or by a factory letting its effluent flow into a nearby river—whenever water is added to a river, i.e. a large portion of water, it does not have to alter beforehand. 41 See Phys. VIII 7, 260a29–32. 42 αὐξήσεως μὲν γὰρ τὸ πέρας τοῦ κατὰ τὴν οἰκείαν φύσιν τελείου μεγέθους, φθίσεως δὲ ἡ τούτου ἔκστασις. Phys. VI 10, 241a33–b2: “the limit of growth is to be found in the complete magnitude proper to the nature of the thing, while the limit of diminution is the loss of such magnitude.” (Transl. Hardie & Gaye with mod.). Does locomotion precede all occurrences of change in quantity? 55 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen