Marsilio Ficino’s Platonic Theology, Volume I

4Again, whatever is moved breaks forth from potency and inactivity into act and seeks some terminus and end of its motion, as though it were not sufficient unto itself but needed that toward which it directs itself by its motion. Yet above whatever passes from inactivity into act there always exists something that is a full and perpetual act. Above whatever is changed through need there necessarily exists something that is not moved, because it either never needs anything or is already utterly full.

5This is especially so because whatever is moved is changed by a desire to advance, and it cannot advance except by acquiring a better and more excellent nature. It does not possess during its motion the thing it seeks, but attains it after the motion—not, indeed, from itself, for why then would it have needed to change, but from some other, richer source.

6For whatever by its own nature lacks a terminus must receive its determination from something more perfect. A mobile thing lacks a terminus of itself, because it does not rest in itself.

7And if a thing of this sort were the principle of things, then, because it would produce everything through its mutable operation, there would be no stability in things. Yet some stability is so necessary in things that even motion itself is not without stability. For unless a thing said to be affected now in one way and now in another through motion remained the same in substance for some span of time, it would neither change its affections nor vary by degrees, but would cease wholly in an instant. The supremely ordered revolution of the heavens about the same center and the same poles, the equality of their motions, and the return of the stars themselves partake of a certain stability. And just as whatever stands does so through unity and is united in stability—a point we shall explain elsewhere—so whatever moves does so for the sake of stability and stands within its motion.