Summa Theologiae Moralis, vol. I: De Principiis

S. Th. I-II, q. 1; C. Gent. III, 1, 2, 3.

Assuming that man is not only, like irrational beings, moved and led toward an end, but properly and formally acts for the sake of an end, knowing it as an end and intending it voluntarily and freely, according to the doctrine of St. Thomas we establish the following theses¹ :

15. Thesis I. Man, in all deliberate and voluntary, that is, human actions, acts in his own manner for the sake of some end or good. — It is proved:

a) From the notion of the good: All actions which proceed from some power are caused by it according to the ratio of its object. But the object of the will is the good and the end. Hence it is necessary that voluntary or human acts be for the sake of an end (q. 1, a. 1).

b) From the notion of the end: In causes that are subordinated per se, of which one does not move unless it is moved by another, there is no infinite regress; rather, with the first removed, it is necessary that the others be removed. But the end is the first among causes, because nothing acts except from a determinate intention of the end: for if an agent were not determined to some effect, it would no more will or do this than that. Therefore all human acts depend on and are derived from the intention of the end, and so are done for the sake of the end (a. 2 and 4).

c) From induction Billuart brings forward the argument²: All human acts are elicited or commanded by the will. Elicited acts are concerned either with the end, and then they are for the sake of the end, which by its goodness allures the will to love it; or with means, and then they are also for the sake of the end, since the will does not will them except for the end. Likewise commanded acts, because the will commands them out of love of the end,

so that through them, as through means, it may attain the end. Therefore³

16. Corollary. — From this it follows that all human acts receive their species (at least physical) from the end, whether a) they are considered actively, as an action proceeding from the agent or a motion by which a man moves himself, and then they have their species from the formal principle; but the principle of the act of the will is its object, which is the good and the end (in intention); — or b) they are considered passively as a passion tending to something, and a motion by which a man is moved by himself to a terminus, and then they are specified by the terminus; but that to which a human act is terminated is what the will intends as the end (in execution) (a. 3).

17. Thesis II. Man in all deliberate acts, at least implicitly, acts for the ultimate end of the whole of life, at least abstractly and as conceived in common, or for the perfect good. — It is proved:

a) From the notion of the good: Everything that man desires, he desires under the aspect of the good; but the good is desired either as the perfect good that satisfies and is the ultimate end, or as a beginning and part of the perfect good, and therefore as tending toward the perfect good and the ultimate end, because a beginning is always ordered to its completion, just as every part is ordered to the whole (a. 6).

b) From the notion of the ultimate end: The ultimate end holds itself in moving the will as the first mover does in motions, because it is first in intention. But in movers, no infinite regress is given, because secondary movers do not move except insofar as they are moved by the first mover. Therefore, secondary goods or intermediate and subordinate ends do not move the appetite except in order to the perfect good, which

is the ultimate end (a. 6). — And indeed, if in ends there were granted an infinite process, and if all ends were intermediate and subordinate, there would be no end which the will would intend for its own sake and in which it would finally rest, no end from which the will would first begin to be moved, and consequently it would never will anything, never begin to operate anything; just as neither would an action once begun ever be terminated. And thus there would be no human act; and even if there were some act, it would be entirely vain (a. 6 and 4).

18. Thesis III. Man cannot simultaneously choose two ultimate ends, but only one.

This must be understood not only of the ultimate end formally taken and in the abstract, or of beatitude in general and the very notion of the highest good, which is evidently one; but also of the ultimate end materially taken in the concrete, i.e., of the thing in which man places his supreme good. Not indeed if the end is considered partially, because to it as parts there can concur several things collectively taken which together constitute one perfect and complete good; but if it were considered totally, because the notion of the highest good cannot be attributed to several things divisively and separately, so that man tends toward several disparate things as toward ultimate ends that are total and adequate, not subordinate to one another, as if each one alone without the others were the whole ultimate end. And therefore Christ says (Mt. VI, 24): No one can serve two masters, namely, ones not subordinate to each other.

It is proved: a) From the fact that the ultimate end has the character of the perfect: A person desires something as an ultimate end which he desires as a good perfect and completive of himself and fully satisfying (from the intention of the one desiring); otherwise he would not rest in it and it would not be the ultimate end; therefore the ultimate end so fills and satisfies the whole appetite of man that nothing outside itself is left to be desired.

And yet it would not fulfill nor fully satisfy if something beyond itself, namely another end, could be desired and required for its perfection.

Hence it cannot be that the will tends toward two things in such a way as if each were its perfect good and ultimate end.

It is confirmed: If there were two ultimate ends, neither would be the highest and full good of the one desiring, neither would perfectly satisfy the appetite, since, with one obtained, the other would still be desirable. Hence they would be simultaneously fully satisfied in power, because they are ultimate ends; and they would not be, because outside each one there would remain something to be desired that would not be subordinated to it, namely, the other end.

b) From the fact that the ultimate end has the nature of the first natural good: What is naturally desired cannot be but one, because nature is determined to one thing and tends only to one; hence, just as one thing has only one form and one species, so too there is only one natural inclination. But the ultimate end, or the supreme good, is naturally desired. Therefore, the ultimate end is one. The minor premise is established by internal experience, and it is also understood: just as in reason the principle is what is known as naturally implanted, so in the will the principle is what is desired by natural tendency; hence, the love of the end, or of the supreme good, is implanted in the will, because it is the principle among things desirable.

c) From the fact that the ultimate end has the character of the first specifying principle: In every genus of causing and operating, there is one principle from which all things are derived; otherwise, the genus would not be one. But all human acts constitute one genus of operating and causing, because all things appetible by the will are of one genus, namely, the good suitable to man; moreover, the ultimate end is the first principle in this genus because it is appetible for its own sake. Therefore, the ultimate end is one. — “Since voluntary actions receive their species from the end,” says St. Thomas, “it is necessary that they receive the character of genus from the ultimate end, which is common” (a. 5)

19. Thesis IV. The ultimate end of man is in reality happiness or beatitude. — It is proved: The ultimate end is the highest and perfect good of man. But beatitude or happiness is nothing other than the possession of this highest good, sufficient and complete, which ultimately perfects and terminates every tendency and fully satisfies and entirely stills all the appetite of the intellectual nature, which knowingly recognizes this its full sufficiency in the good and rejoices in it (I, q. 26, a. 1). Therefore the ultimate end of man is beatitude. Hence beatitude can be defined both objectively: the perfect good entirely stilling and satisfying the appetite (q. 2, a. 8), or the most complete good which completes the whole appetite of the rational agent, so that nothing remains to be desired, or the perfect and sufficient good, excluding every evil and fulfilling every desire (q. 5, a. 3), the ultimate perfection of the rational or intellectual nature (I, q. 62, a. 1); — and formally: the stable possession and rest in ultimate perfection, the possession of the perfect good which entirely stills our desire, or the state made perfect by the aggregation of all goods (Boethius).

That this beatitude truly exists and is possible for us is proved: Man by innate appetite and instinctive necessity tends toward perfect beatitude, so that it is impossible not to think of it frequently and not to desire it, or sincerely to will the opposite. But an innate appetite cannot be empty, otherwise our nature would be ill-constituted; moreover, it is repugnant to God's wisdom, truth, and goodness that He should have implanted in us an inclination and appetite toward something that does not exist or that we cannot attain. Therefore.

20. Corollaries. — 1. The end is the cause, origin, and root of all affections. This "can be declared more fully not only by the example of light, which, because it is the first and highest visible object, is the reason for seeing all distinctions of colors; or by the example of the motion of the heart, which, because it is the first motion of life, is the cause from which all vital motions flow; but still far more clearly by the comparison, very frequent in St. Thomas, of the intellect with the will. For thus the love of the ultimate end stands among appetible things, as the cognition of principles stands among intelligible things; whence just as first principles are the first things known, so beatitude or the ultimate end is the first thing willed. And just as we do not assent to particular conclusions except insofar as they cohere with first principles, so neither do we will particular goods except insofar as they are connected with the ultimate end, namely, beatitude. And finally, just as cognition of principles moves to all other cognitions, insofar as, illumined through it, we understand the rest, and therefore it is the root of all cognitions—indeed, the other cognitions are nothing but certain propagations and diffusions of that first light—so that first love of beatitude moves to other loves, insofar as, excited through it, we seek those things which lead to it, and it is the first root of all affections; indeed, the other affections are nothing but certain branches, offshoots, and diffusions of that first love; or lines born from this circumference, and terminated in its center, namely, beatitude. Whence Boethius, 3 de Cons., Prose 2, says splendidly: All the care of mortals, which the labor of manifold pursuits exercises, proceeds indeed by a different path, but still strives to arrive at one end of beatitude. And St. Augustine, l. 13 de Trin., c. 5: All men wish to be happy, and this they desire most ardently, and on account of this they desire other things. Thus Goudin, Phil. p. 3, q. 1, a. 1, § 1, concl. 2.

2. Beatitude can be considered: a) In the abstract, and thus it is the universal and complete good that man necessarily wills and cannot not will, and therefore in this all agree. b) In the concrete, for the thing whose possession should make us blessed and perfectly good, and thus man who does not possess it, freely tends toward it, because he does not necessarily see the necessary connection of this or that good with beatitude; whence under this respect men do not agree on the ultimate end (q. 5, a. 8; q. 1, a. 7).