Seite - 33 - in The Priority of Locomotion in Aristotle’s Physics

change may or may not occur in the cosmos. He first of all rejects the the- ory that everything is always changing, and, again, the theory claiming that there is no change at all and everything is at permanent rest.69 The only plausible options, he argues, are either (1) that all things are sometimes in motion and sometimes at rest, or (2) that besides the things that are chan- ging between change and a state of rest, there are some things that are always undergoing change and others that are always at rest. It is the task of Phys. VIII 4–6 to examine which of these two options is correct.70 In Phys. VIII 4 Aristotle begins this task by establishing the claim that for whatever is changing there must be some cause of this change71: either what is changing is itself the cause of its change, i.e. a self-mover, or its change is caused by some other thing. Phys. VIII 5 then directly continues this train of thought and shows that each thing that is in the state of change, but is not a self-mover, must have a first cause of change that is a self-mover72, which, as Aristotle points out in this context, may be further analysed into a moving and an unmoving part73—a step that is essential for the further development of the argument. This line of reasoning is then completed in Phys. VIII 6, where Aristotle shows that for the stated reasons there must be one unmoved mover that is the source of all change.74 This unmoved mover is eternal and causes an eternal change that is always one and the same, i.e. not composed of different changes, and therefore continuous as a whole.75 By establishing the theory of the necessary existence of the first unmoved mover, Aristotle seems to have finished his examination, as the task which was set out at the end of Phys. VIII 3 is accomplished: according to this the- ory developed throughout chapters 1–6, it is clear now that in the cosmos there are things that are always undergoing change, others that are always at rest, and still others that are sometimes at rest and sometimes undergoing change.76 Contrary to what one might expect, however, Aristotle’s inquiry does not end after Phys. VIII 6, but continues by arguing first of all that locomotion is the primary of the four kinds of change (VIII 7) and that circular locomo- tion is the primary type of locomotion and the kind of change that alone 69 See Phys. VIII 3, 254a35–b4. 70 λοιπὸν οὖν θεωρῆσαι πότερον πάντα τοιαῦτα οἷα κινεῖσθαι καὶ ἠρεμεῖν, ἤ ἔνια μὲν οὕτως, ἔνια δ᾽ ἀεὶ ἠρεμεῖ, ἔνια δ᾽ἀεὶ κινεῖται· τοῦτο γὰρ δεικτόν ἡμῖν. Phys. VIII 3, 254b4–6. 71 ἅπαντα ἂν τὰ κινούμενα ὑπό τινος κινοῖτο. Phys. VIII 4, 256a3. 72 See Phys. VIII 5, 258b4–9. 73 See Phys. VIII 5, 258a1–2. 74 See for instance Phys. VIII 6, 259a6–13, and 259a13–20. 75 See Phys. VIII 6, 259a13–20, and 260a17–19. 76 See Phys. VIII 6, 260a11–19. Physics VIII 33 ISBN Print: 9783525253069 — ISBN E-Book: 9783647253060 © 2014, Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen