This is impossible in the case of two lords who are necessary in themselves and beginningless; for this one (1) would not possess power (2), nor be a lord or an agent, until the other made him so, and likewise the other. It is equivalent to saying:
“This one would not exist until the other brought him into existence.”
This is necessarily impossible, as was previously indicated (3). Circular prior dependence is intrinsically impossible by the agreement of all rational people, as in the case of circularity among agents and causes. It is therefore impossible for each of two things to be the cause of the other and the agent that produces it, or to be a component of its cause and producing agent. Thus, if each could be capable or an agent only through the other, each would necessarily be an efficient cause—or a cause (4) required to complete that by which (5) the other becomes capable and an agent. This is necessarily impossible by the agreement of all rational people. It follows that a lord must possess power in himself. If he possesses power in himself and can will something contrary to what the other wills (6), then they can differ; but if he can will only what the other wills (7), incapacity necessarily follows.
Thus, if it is posited that this one can will and act only as the other wills and acts (8), the incapacity of each necessarily follows. Indeed, this (9) is also intrinsically impossible, just as, if [this one could not possess power until the other possessed power,] (10) that would be intrinsically impossible. [Thus, if this one