of all their various kinds of motion. Rather, the mover must be something other than it. The moving bodies distinct from it do not derive their motion from it alone, but from it and from something else. Thus none of them moves things independently, and whatever depends on something else cannot be necessary in existence through itself.

There must therefore be a mover distinct from them.

One may likewise argue:

None of them independently brings about the benefits enjoyed by the lower world or the effects that arise within it. These result only from various causes, including the celestial bodies’ joint action and things existing in the lower world that do not come from any one of those bodies. Each therefore requires a partner to assist it and faces an impediment that obstructs its effects. Its work can be accomplished only through a partner that has no need of it and through the absence of an opposing impediment. It cannot, therefore, be the creator of either its partner, which has no need of it, or the impediment that opposes it. Nor can the benefits arising in the lower world result solely from its intention and action. There must therefore be something other than it that necessitates its action and motion. This is what it means to be commanded and made subservient.

For if the motion is forced, there must be something that forces it.

If it is natural, natural motion presupposes that the entity has left its proper place, and it must have been forced to leave.

If it is voluntary, then whatever wills effects that it cannot produce independently—which arise only through the participation of something else and are prevented by something else opposing it—depends on something else to achieve its aim.

It cannot be necessary in existence through itself, because whatever is necessary through itself cannot depend in any respect on something else that has no need of it. For if it depended on something else in any respect, it would not, in that respect, be independent of that other, but dependent on it.