Seite - 87 - in The Priority of Locomotion in Aristotle’s Physics

thing grows, some additional material is added, while if something diminishes, something of what we call the change’s subject is taken away. He would part ways with Aristotle, however, in claiming that this is all that happens: what we, for instance, call the growth process that an infant undergoes, is not a special kind of change, but merely the movement of the basic material parts of which the infant consists and those which are added in the process of growth. If this were the case, then the principle of irreduci- bility would clearly be violated, for then nothing besides change in place would occur. The reductionist’s understanding of growth indeed is compatible with the basic assumptions stated above. Yet, it does not necessarily follow from the fact that whatever changes in size also changes in place with respect to its parts. Because from what I have said here and in the previous chapter it has become clear that for Aristotle the process of growth in living beings is much more than the movement of the subject’s material constituents. I can only give a rough outline of the reasons for this here, since a thorough treat- ment of this matter presupposes dealing with fundamental ontological assumptions that underlie both Aristotle’s and the reductionist’s views. For my purposes the following should suffice. The reductionist is not capable of explaining the core feature of change in quantity, namely that a substance increases or decreases in size by material either being added to or taken away from that which undergoes this change, while this subject nevertheless remains what it is. Let us return to the example of the growing infant. It is the infant’s form, and not its matter, that is primarily responsible for its being an infant, i.e. a human being, although matter is necessary for the infant’s being a human being as well. The reductionist basically reduces the infant, or any other substance, to its material constituents and neglects the form, which is an essential part of a hylomorphic composite. In other words, he is unaware of the fact that entities like human beings are more than—to put it boldly—mere heaps of matter, and are what they are only in virtue of their respective form. According to Aristotle, the problem with many of the earlier thinkers was that they took matter to be the only princi- ple of nature and were not aware of the existence of another principle, namely form.33 Form, however, plays a crucial role in the processes of growth and diminution: what grows or diminishes does so with respect to its form, otherwise there is no reason for the subject to remain what it is and to fulfil its essence, i.e. the criteria that something needs to meet in order to belong to a certain class of beings. If an appendage like my hand grows and is to remain this same appendage with a specific function in the whole of the organism, it needs to increase in size in proportion to the rest 33 See for instance Phys. I 2, 194a18–21. What changes in quantity changes with respect to place 87 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen