I answer that, The Platonists [*Phaedo. xlix: Tim. (Did.) vol. ii, p. 218] asserted that the forms which are in matter are caused by immaterial forms, because they said that the material forms are participations of immaterial forms. Avicenna followed them in this opinion to some extent, for he said that all forms which are in matter proceed from the concept of the intellect; and that corporeal agents only dispose [matter] for the forms. They seem to have been deceived on this point, through supposing a form to be something made per se, so that it would be the effect of a formal principle. But, as the Philosopher proves (Metaph. vii, Did. vi, 8), what is made, properly speaking, is the composite: for this properly speaking, is, as it were, what subsists. Whereas the form is called a being, not as that which is, but as that by which something is; and consequently neither is a form, properly speaking, made; for that is made which is; since to be is nothing but the way to existence.
Now it is manifest that what is made is like to the maker, forasmuch as every agent makes its like. So whatever makes natural things, has a likeness to the composite; either because it is composite itself, as when fire begets fire, or because the whole "composite" as to both matter and form is within its power; and this belongs to God alone. Therefore every informing of matter is either immediately from God, or form some corporeal agent; but not immediately from an angel.
Reply Obj. 1: Our soul is united to the body as the form; and so it is not surprising for the body to be formally changed by the soul's concept; especially as the movement of the sensitive appetite, which is accompanied with a certain bodily change, is subject to the command of reason. An angel, however, has not the same connection with natural bodies; and hence the argument does not hold.
Reply Obj. 2: Whatever an inferior power can do, that a superior power can do, not in the same way, but in a more excellent way; for example, the intellect knows sensible things in a more excellent way than sense knows them. So an angel can change corporeal matter in a more excellent way than can corporeal agents, that is by moving the corporeal agents themselves, as being the superior cause.
Reply Obj. 3: There is nothing to prevent some natural effect taking place by angelic power, for which the power of corporeal agents would not suffice. This, however, is not to obey an angel's will (as neither does matter obey the mere will of a cook, when by regulating the fire according to the prescription of his art he produces a dish that the fire could not have produced by itself); since to reduce matter to the act of the substantial form does not exceed the power of a corporeal agent; for it is natural for like to make like. _______________________
THIRD ARTICLE [I, Q. 110, Art. 3]
Whether Bodies Obey the Angels As Regards Local Motion?
Objection 1: It would seem that bodies do not obey the angels in local motion. For the local motion of natural bodies follows on their forms. But the angels do not cause the forms of natural bodies, as stated above (A. 2). Therefore neither can they cause in them local motion.
Obj. 2: Further, the Philosopher (Phys. viii, 7) proves that local motion is the first of all movements. But the angels cannot cause other movements by a formal change of the matter. Therefore neither can they cause local motion.
Obj. 3: Further, the corporeal members obey the concept of the soul as regards local movement, as having in themselves some principle of life. In natural bodies, however, there is no vital principle. Therefore they do not obey the angels in local motion.