From the third question of the “Ethics.”

IS happiness something uncreated? The word end has two meanings. In one meaning it stands for the thing itself which we desire to gain: thus the miser’s end is money. In another meaning it stands for the near attainment, or possession, or use, or enjoyment of the thing desired, as if one should say that the possession of money is the miser’s end, or the enjoyment of something pleasant the end of the sensualist. In the first meaning of the word, therefore, the end of man is the Uncreated Good, namely God, who alone of his infinite goodness can perfectly satisfy the will of man. But according to the second meaning, the last end of man is something created, existing in himself, which is nothing else than the attainment or enjoyment of the last end. Now the last end is called happiness. If therefore the happiness of man is considered in its cause or object, in that way it is something uncreated; but if it is considered in essence, in that way happiness is a created thing.

  Happiness is said to be the sovereign good of man, because it is the attainment or enjoyment of the sovereign good.

  So far as the happiness of man is something created, existing in the man himself, we must say that the happiness of man is an act. For happiness is the last perfection of man. But everything is perfect so far as it is in act; for potentiality without actuality is imperfect. Happiness therefore must consist in the last and crowning act of man. But it is manifest that activity is the last and crowning act of an active being; whence also it is called by the philosopher “the second act.” And hence it is that each thing is said to be for the sake of its activity. It needs must be therefore that the happiness of man is a certain activity.

  Life has two meanings. One way it means the very being of the living, and in that way happiness is not life; for of God alone can it be said that his own being is his happiness. In another way life is taken to mean the activity on the part of the living thing by which activity the principle of life is reduced to act. Thus we speak of an active or contemplative life, or of a life of pleasure; and in this way the last end is called life everlasting, as is clear from the text: “This is life everlasting, that they know thee, the only true God.”

  By the definition of Boëtius, that happiness is “a state made perfect by the aggregate sum of all things good,” nothing else is meant than that the happy man is in a state of perfect good. But Aristotle has expressed the proper essence of happiness, showing by what it is that man is constituted in such a state, namely, by a certain activity.

  Action is twofold. There is one variety that proceeds from the agent to exterior matter, as the action of cutting and burning, and such an activity cannot be happiness, for such activity is not an act and perfection of the agent, but rather of the patient. There is another action immanent, or remaining in the agent himself, as feeling, understanding, and willing. Such action is a perfection and act of the agent, and an activity of this sort may possibly be happiness.

  Since happiness means some manner of final perfection, happiness must have different meanings according to the different grades of perfection that there are attainable by different beings capable of happiness. In God is happiness by essence, because his very being is his activity, because he does not enjoy any other thing than himself. In the angels final perfection is by way of a certain activity, whereby they are united to the uncreated good; and this activity is in them one and everlasting. In men, in the state of the present life, final perfection is by way of an activity whereby they are united to God. But this activity cannot be everlasting or continuous, and by consequence it is not one, because an act is multiplied by interruption; and, therefore, in this state of the present life, perfect happiness is not to be had by man. Hence the philosopher, placing the happiness of man in this life, says that it is imperfect, and after much discussion he comes to this conclusion: “We call them happy, so far as happiness can be predicated of men.” But we have a promise from God of perfect happiness, when we shall be “like the angels in Heaven.” As regards this perfect happiness, the objection drops, because in this state of happiness the mind of man is united to God by one continuous and everlasting activity. But in the present life, so far as we fall short of the unity and continuity of such an activity, so much do we lose of the perfection of happiness. There is, however, granted us a certain participation in happiness, and the more continuous and undivided the activity can be the more will it come up to the idea of happiness. And therefore in the active life, which is busied with many things, there is less of the essence of happiness than in the contemplative life, which is busy with the one occupation of the contemplation of truth.