Marsilio Ficino’s Platonic Theology, Volume I

12Such is the motion found in the reason of heavenly souls. Although this middle part, when turned toward mind, sees all principles at once, their lowest part is most closely akin to mutable bodies and does not possess power enough to be carried toward all seeds in a single act. Yet it desires to be borne toward them all in actuality, lest all that lies within its potency should lie there in vain. It therefore moves toward them by a manifold striving, now attaining this seed in actuality and now that, but losing its former actual objects when it passes into others. Thus it does not embrace all at once, though it is always striving toward all. It runs forever, and this kind of course is the first motion; the interval of this course is the first time. The world runs in accord with that course, and the times of the world flow in accord with that time. I believe this is Proteus himself changing forms, as he appears in Orpheus. Since those seeds are limited to a definite number while soul runs forever, it passes through them all in a definite span of time. Once they have been traversed, soul is compelled either to rest, as it seems to us, or gradually to run through them all anew and weave again in the world the same fabric of generation. So Zoroaster held: when at some time the same causes have completely returned, the same effects return in the same way. By this reasoning both he and many later followers confirmed the resurrection of human bodies. The Platonists held that the circuit of the universe is completed in thirty-six thousand solar years, a period they call the great or cosmic year. Mercury calls its end the old age of the world; Plato, in the *Statesman*, calls it the restoration of the world.

13To understand more clearly how heaven is moved, consider an example. Euclid decides to leave Megara by night and go to Athens to hear Socrates, and so takes up a lantern. First he traces out the whole journey in a general conception.

14No particular step follows from this universal plan unless a particular thought intervenes to mark out the first step. The lantern therefore reveals that first step; imagination at once conceives it, appetite chooses it, and the feet accomplish it. Once it is complete, the lantern reveals the second step; Euclid conceives, desires, and completes that one in turn.