Marsilio Ficino’s Platonic Theology, Volume II

2Consequently, whatever ceases to be loses its own being because it is separated from its proper form, just as it first began to be when it acquired that form. A thing composed of matter and form therefore perishes when it is severed from its form. Take fire, composed of its bodily mass and its natural heat. The cold of water or earth can insinuate itself into the matter of fire and drive out its natural heat, the form of fire. Once that form has been expelled, the fire ceases to be. Thus fire, composed of matter and a certain kind of heat, loses its being when it loses its heat—by which I mean its substantial form together with that form's properties, though for the purpose of the argument we now call it ‘heat’ because it has no readily evident name. But when does heat itself lose its being, since heat is a form and being comes from form? When, of course, it is driven out of that matter. In composite things, being is naturally attributed to the whole, not to the parts. Properly speaking, the being of the composite fire belongs neither to its matter alone nor to its heat. When heat was drawn from the seed of matter by a natural agent in the generation of fire, it was extended throughout all the fire's matter on the condition that it depend entirely upon that matter. Heat thus had no being proper to itself; rather, through the common being of the whole fire, heat too was said to be. That common being ceases when the two parts are separated from one another. When their common being ceases, the form that flourished through it also perishes. Matter, however, does not perish, for it at once receives another form through which it exists. When it loses a determinate heat, it loses fiery being; when it receives a determinate coldness or moisture, it takes on earthy or watery being. Conclude, then, that a composite thing such as fire or water perishes when it is separated from its form, while the form itself perishes when it departs from the law of its fashioner. The sun that generated the fire was its fashioner. By its law the sun drew heat from the tinder of that matter so that the heat, lying in the matter, would be contained under the being of the composite whole. Heat transgresses this law when it leaves the matter; it leaves when cold drives it away. How, then, can that which departs neither from its form nor from the law of its fashioner perish, since the being of each thing proceeds from form and is preserved by the fashioner's law?