If therefore there be any thing, whose nature is unchangeable; the natural mode of whose being cannot be exceeded by the continuation of any pleasing object; and which can behold the whole object of its delight at once---to such a one change will afford no delight. And the more any pleasures approach to this, the more are they capable of being continual.
Reply to Objection 1: Although the subject of movement has not yet perfectly that to which it is moved, nevertheless it is beginning to have something thereof: and in this respect movement itself has something of pleasure. But it falls short of the perfection of pleasure; because the more perfect pleasures regard things that are unchangeable. Moreover movement becomes the cause of pleasure, in so far as thereby something which previously was unsuitable, becomes suitable or ceases to be, as stated above.
Reply to Objection 2: Movement causes toil and fatigue, when it exceeds our natural aptitude. It is not thus that it causes pleasure, but by removing the obstacles to our natural aptitude.
Reply to Objection 3: What is customary becomes pleasant, in so far as it becomes natural: because custom is like a second nature. But the movement which gives pleasure is not that which departs from custom, but rather that which prevents the corruption of the natural mode of being, that might result from continued operation. And thus from the same cause of connaturalness, both custom and movement become pleasant.
Whether hope and memory causes pleasure?
Objection 1: It would seem that memory and hope do not cause pleasure. Because pleasure is caused by present good, as Damascene says (De Fide Orth. ii, 12). But hope and memory regard what is absent: since memory is of the past, and hope of the future. Therefore memory and hope do not cause pleasure.
Objection 2: Further, the same thing is not the cause of contraries. But hope causes affliction, according to Prov. 13:12 : "Hope that is deferred afflicteth the soul." Therefore hope does not cause pleasure.
Objection 3: Further, just as hope agrees with pleasure in regarding good, so also do desire and love. Therefore hope should not be assigned as a cause of pleasure, any more than desire or love.
On the contrary, It is written ( Rom. 12:12 ): "Rejoicing in hope"; and ( Ps. 76:4 ): "I remembered God, and was delighted."
I answer that, Pleasure is caused by the presence of suitable good, in so far as it is felt, or perceived in any way. Now a thing is present to us in two ways. First, in knowledge---i.e. according as the thing known is in the knower by its likeness; secondly, in reality---i.e. according as one thing is in real conjunction of any kind with another, either actually or potentially. And since real conjunction is greater than conjunction by likeness, which is the conjunction of knowledge; and again, since actual is greater than potential conjunction: therefore the greatest pleasure is that which arises from sensation which requires the presence of the sensible object. The second place belongs to the pleasure of hope, wherein there is pleasurable conjunction, not only in respect of apprehension, but also in respect of the faculty or power of obtaining the pleasurable object. The third place belongs to the pleasure of memory, which has only the conjunction of apprehension.
Reply to Objection 1: Hope and memory are indeed of things which, absolutely speaking, are absent: and yet those are, after a fashion, present, i.e. either according to apprehension only; or according to apprehension and possibility, at least supposed, of attainment.
Reply to Objection 2: Nothing prevents the same thing, in different ways, being the cause of contraries. And so hope, inasmuch as it implies a present appraising of a future good, causes pleasure; whereas, inasmuch as it implies absence of that good, it causes affliction.
Reply to Objection 3: Love and concupiscence also cause pleasure. For everything that is loved becomes pleasing to the lover, since love is a kind of union or connaturalness of lover and beloved. In like manner every object of desire is pleasing to the one that desires, since desire is chiefly a craving for pleasure. However hope, as implying a certainty of the real presence of the pleasing good, that is not implied either by love or by concupiscence, is reckoned in preference to them as causing pleasure; and also in preference to memory, which is of that which has already passed away.
Whether sadness causes pleasure?
Objection 1: It would seem that sadness does not cause pleasure. For nothing causes its own contrary. But sadness is contrary to pleasure. Therefore it does not cause it.
Objection 2: Further, contraries have contrary effects. But pleasures, when called to mind, cause pleasure. Therefore sad things, when remembered, cause sorrow and not pleasure.
Objection 3: Further, as sadness is to pleasure, so is hatred to love. But hatred does not cause love, but rather the other way about, as stated above (Q[29], A[2]). Therefore sadness does not cause pleasure.
On the contrary, It is written ( Ps. 41:4 ): "My tears have been my bread day and night": where bread denotes the refreshment of pleasure. Therefore tears, which arise from sadness, can give pleasure.
I answer that, Sadness may be considered in two ways: as existing actually, and as existing in the memory: and in both ways sadness can cause pleasure. Because sadness, as actually existing, causes pleasure, inasmuch as it brings to mind that which is loved, the absence of which causes sadness; and yet the mere thought of it gives pleasure. The recollection of sadness becomes a cause of pleasure, on account of the deliverance which ensued: because absence of evil is looked upon as something good; wherefore so far as a man thinks that he has been delivered from that which caused him sorrow and pain, so much reason has he to rejoice. Hence Augustine says in De Civ. Dei xxii, 31 [*Gregory, Moral. iv.] that "oftentimes in joy we call to mind sad things . . . and in the season of health we recall past pains without feeling pain . . . and in proportion are the more filled with joy and gladness": and again (Confess. viii, 3) he says that "the more peril there was in the battle, so much the more joy will there be in the triumph."
Reply to Objection 1: Sometimes accidentally a thing is the cause of its contrary: thus "that which is cold sometimes causes heat," as stated in Phys. viii, 1. In like manner sadness is the accidental cause of pleasure, in so far as it gives rise to the apprehension of something pleasant.
Reply to Objection 2: Sad things, called to mind, cause pleasure, not in so far as they are sad and contrary to pleasant things; but in so far as man is delivered from them. In like manner the recollection of pleasant things, by reason of these being lost, may cause sadness.
Reply to Objection 3: Hatred also can be the accidental cause of love: i.e. so far as some love one another, inasmuch as they agree in hating one and the same thing.
Whether the actions of others are a cause of pleasure to us?
Objection 1: It would seem that the actions of others are not a cause of pleasure to us. Because the cause of pleasure is our own good when conjoined to us. But the actions of others are not conjoined to us. Therefore they are not a cause of pleasure to us.
Objection 2: Further, the action is the agent's own good. If, therefore, the actions of others are a cause of pleasure to us, for the same reason all goods belonging to others will be pleasing to us: which is evidently untrue.