Marsilio Ficino’s Platonic Theology, Volume I

4The elements and members of the world are contrary in nature and struggle against one another in form or power. How could they come together as one, remain joined for so long, and exchange natures and motions with one another—both giving and receiving—unless some one higher power bound them together? If the governance of the world were left to these mutually opposed members, each would be held in balance by its own weight and separated in its own place, and they would never mingle.

5Even if they mingle, they will produce nothing beyond things hot and cold, dry and moist, rare and dense, and others of the same kind; they will establish no order of forms, figures, or revolutions. In the arts, likewise, such order is made neither by the material nor by the tools, but by the artist's thought alone. And although heaven in some measure governs the elements, it cannot govern them without itself being governed from elsewhere.

6For the great diversity within heaven—of forms, powers, and motions—is directed into a single stable order, not by the heavenly bodies, which are of their own nature diverse and mobile, but by a higher power that is in itself wholly one and stable.

7Finally, every natural agent, whether elemental or heavenly, always depends upon something else: first, because it is mobile and therefore needy and imperfect; and second, because whatever it does, it does with its whole being under the necessity of nature. It must therefore receive from some higher ruler the measure and manner of action that, through definite degrees, accords with a definite end. Heat, whether as form or as power, simply dissolves everywhere and without qualification, while cold condenses.