Commentaria in Summam contra Gentiles, Liber III

I. In the fourth place,¹ it is shown that man's highest good cannot consist in worldly power either.

And it is argued first as follows. In obtaining it, fortune has the greatest power; and it is unstable; and it is not subject to man's will; and it very often comes to the wicked; all of which are incompatible with the highest good. Therefore, etc.

It must be noted, from I-II, q. 2, a. 4, that man is ordered to beatitude through intrinsic principles, since he is naturally ordered to it. Therefore, from the fact that certain goods come solely from without, and especially from fortune, it is rightly concluded that such is not man's highest good, and that beatitude does not consist in it.

Secondly. If this were so, man would be called good according to his having power, because a man is called good especially according as he attains to the highest good. But this is false, because not everyone who can do good things is good. Therefore, etc.

Thirdly. Every power is relative to another. But not the highest good. Therefore, etc.

Note that power, as is clear from Metaph. V,² has the nature of a principle. But a principle is spoken of in relation to another, namely, to that which is from the principle. Therefore, it is rightly said here that power is relative to another.

Fourthly. A man can use power well and badly, since rational powers are for opposites. But this is incompatible with man's highest good. Therefore, etc.

Fifthly. Human power is most imperfect, because it is rooted in the wills and opinions of men, in which there is the greatest inconstancy. And the more it is esteemed,³ the more it depends on many people, and consequently it can be destroyed in multiple ways. Therefore, etc. — The consequence is clear, because if any power were the highest good, it would have to be most perfect.

From what was said above, St. Thomas universally concludes that man's happiness consists in no external good, since all such goods are contained under the aforementioned.

II. Against this conclusion it can be argued: both because through power men are close to God, and because through power one is sufficient for himself and for others.

But neither of these is convincing. Not indeed the first: because, as St. Thomas says in the place cited above, ad 1, it does not suffice for beatitude that a man approach God in respect of power, but it is also required that he approach in respect of goodness. This does not belong to man from human power, since he can use it well and badly; God, however, cannot use His power except well, since His power is His goodness.

Nor does the second press. For it does not suffice for beatitude that someone be in some respects sufficient for himself and for others; rather, it is required that that by which he is sufficient for himself and for others be related only to good, and not to good and evil, as is the case in worldly power.