부산대학교 도서관

Aristotle notoriously begins his examination of being in the sense of dunamisand energeiain MetaphysicsTheta with what he describes as the sense that is ‘most dominant’ but not useful for his present aim. He proceeds to define the not-useful sense of dunamisas “the principle of change in something else or in itself qua other”, along with other senses derived from this primary sense. But what then is the useful sense? All that Aristotle tells us at the outset is that it is a sense that extends “beyond things spoken of only in relation to motion” and nowhere in Book Theta does he explicitly identify the useful sense as such. This has allowed for very different interpretations of the useful sense in the literature, the primary ones being that it is (1) ‘possibility’, (2) the potential to receive a form, (3) being-potentially-x understood modally as encompassing all specific senses of dunamis, and (4) capacity for substantial change. The present paper argues that there are significant problems with all of these suggestions and defends an identification of the useful sense of dunamiswith the sense that Aristotle explicitly opposes to the not-useful sense at the start of Theta 8: phusis(‘nature’). This goes hand-in-hand with an identification of the useful sense of energeiawith ‘activity’ as distinguished from motion/change at the end of Theta 6. What makes these senses of dunamisand energeiathe useful ones for Aristotle’s present aim is that they are required to explain fully the priority of energeiato dunamisin substance defended in Theta 8, they support the identification in Theta 9 of energeia with the good, and they explain the unity of the only substances that Aristotle recognizes as being genuinely substances: natural living substances.