more perfect in its existence, all the more so since the latter is superior in every respect. It is therefore impossible for what is inferior in every respect to possess exclusively a perfection that does not belong to what is superior in every respect. Rather, whatever such perfection belongs to the inferior, the superior is more entitled to possess; it must therefore belong to the superior with all the more reason. Moreover, the creature acquires that perfection only from the Creator, and the One who makes another perfect is more entitled to perfection than that other. Thus, He who grants another power is more entitled to power; He who imparts knowledge to another is more entitled to knowledge; and He who gives another life is more entitled to life.

The philosophers agree with this and say:

“Every perfection in an effect derives from its cause, and the cause is more entitled to that perfection.”

Once it is established that such perfection is possible for Him, whatever of this potentially existent perfection is possible for Him belongs to Him necessarily, without depending on anything else. For if it depended on something else, He would possess it only through that other. If that other were His creation, this would entail the impossible “circular causal dependence,” since whatever exists in that other derives from Him. It is impossible for each of two things to be the cause of the other: this is “circular causal dependence.” Since a thing cannot be its own cause, it is all the more impossible for it to be the cause of its own cause.

Likewise, it is impossible for each of two things to produce that which enables the other to act as a cause. Nor can each of two things bestow perfection upon the other, for the giver of perfection is more entitled to perfection. This would require each to be more perfect than the other, which is intrinsically impossible. It would mean that this one is superior to that one, while that one is superior to this one. Yet the superiority of either precludes the other from being its equal, and therefore all the more certainly precludes the other from being superior to it.