elemental bodies; and if it is not what produces those bodies, then it is dependent upon something it did not (1) produce. Even if it is assumed to exert causal influence upon them, it does not do so independently, for the effects arising in them do not (2) come about except through a combination of conjunctions and motions brought about by something other than it.

It is thus clear that its causal influence is conditional upon that of another. This influence is one of its perfections, for that which produces effects is more perfect than that which does not. Yet it depends upon another for this perfection and therefore cannot be necessarily existent in itself. It is consequently clear on both grounds that it is not necessarily existent in itself. It is [also] clear that its maker (3) is not independent of the maker of those things upon which the sphere depends. This is because the sphere is not separate and wholly independent, in every respect, of everything else; rather, it depends upon other created things. It is therefore neither necessarily existent in itself nor the product of an agent independent of the agent responsible for all else.

[The Impossibility of Two Lords of the World]

If this is the case with the outermost sphere, it is even clearer in the case of everything else. Whatever thing in the world (4) you consider, you will find it dependent upon some other thing in the world. This—together with its being [contingent and dependent, not necessarily existent in itself] (5)—shows you (6) that it depends upon the agent that produced that other thing (7). Thus, there cannot be two agents in the world whose respective actions and products are independent of the actions and products of the other. Take a human being, for example: it is impossible for the one who created him to be