Marsilio Ficino’s Platonic Theology, Volume II

7We shall examine the particles in the same way. Since they are divisible to infinity, we shall always find new and ever more numerous movers. We shall never arrive at one, because division always leaves us with many; nor shall we ever arrive at the first movers or the first mover, because our division proceeds without end. Nowhere, therefore, in the substance of body is there one first mover belonging to it. Body accordingly possesses within itself no origin of its own motion by which it could truly be said to move from itself. We are instead compelled to arrive at something impartible from which the origin of all bodily motion arises. The inward mover of body is the soul: while it is present, bodies are in a certain way borne of their own accord in every direction; when the soul is absent, they need something external to set them in motion.

8If this inward mover too were a body, it too would need a mover—an inward mover, I mean—since all living things move without an external impulse. That innermost mover will therefore be the soul itself, which must move of itself, because bodies appear to possess through soul the power of moving themselves. Everything of this kind must be referred back to some nature that is truly its own mover. Thus the soul moves properly of itself if, by participating in it, other things acquire the capacity to move in some manner of themselves. The soul, then, is not a body, nor is it a form scattered throughout a body. Such a form likewise cannot move itself by the arguments given above, for it is subject to the same conditions as body, as has become clear.