The Mereology of Potentiality (Thursday - Week 4, TT19)

mereology of potentiality

In Physics III.3, Aristotle gives his own causal theory of change. He states that a change is the actuality of the movable brought about by the action of the mover, and the actuality belongs to both the mover and the movable. But he also thinks that the mover does not move in the very motion which is caused by itself. Some scholars see an inconsistence in Aristotle’s arguments and argue that he cannot insist both that there is an actuality of the mover and that the mover does not move at all. Moreover, they attempted different ways to explain away the mover being unmoved. This paper argues that Aristotle’s arguments are cogent. As I see it, there is a single motion which belongs to both the mover and the movable. Even if the motion belongs to the mover, it does not move, because the mover is not the subject of the motion, but rather is the principle and form of the motion. Aristotle has good reasons to say that the mover has its own actuality in the movable and it is not moved by actualizing its own active potentiality. It is hard for moderns to understand Aristotle’s theory of change, owing to different metaphysical commitments of causes and causation.

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The Mereology of Potentiality Seminar Convenors: Anna Marmodoro and Andrea Roselli