Book 10: Pleasure.
Chapter 4: Pleasure defined: its relation to activity.
As to the nature or quality of pleasure, we shall more readily discover it if we make a fresh start as follows:—
Vision seems to be perfect or complete at any moment; for it does not lack anything which can be added afterwards to make its nature complete. Pleasure seems in this respect to resemble vision; for it is something whole and entire, and it would be impossible at any moment to find a pleasure which would become complete by lasting longer.
Therefore pleasure is not a motion; for every motion requires time and implies an end (e.g. the motion of building), and is complete when the desired result is produced—either in the whole time therefore, or in this final moment of it. But during the progress of the work all the motions are incomplete, and specifically different from the whole motion and from each other; the fitting together of the stones is different from the fluting of the pillar, and both from the building of the temple. The building of the temple is complete; nothing more is required for the execution of the plan. But the building of the foundation and of the triglyph are incomplete; for each is the building of a part only. These motions, then, are specifically different from one another, and it is impossible to find a motion whose nature is complete at any moment—it is complete, if at all, only in the whole time.
It is the same also with walking and the other kinds of locomotion. For though all locomotion is a motion from one place to another, yet there are distinct kinds of locomotion, as flying, walking, leaping, etc. Nay, not only so, but even in walking itself there are differences, for the whence and whither are not the same in the entire course and in a portion of the course, or in this portion and in that, nor is crossing this line the same as crossing that; for you do not cross a line simply, but a line that is in a given place, and this line is in a different place from that. I must refer to my other works for a detailed discussion of motion; but it seems that it is not complete at any moment, but that its several parts are incomplete, and that they are specifically different from one another, the whence and whither being a specific difference.
Pleasure, on the other hand, is complete in its nature at any moment. It is evident, therefore, that these two must be distinct from each other, and that pleasure must be one of the class of whole and complete things. And this would also seem to follow from the fact that though duration is necessary for motion, it is not necessary for pleasure—for a momentary pleasure is something whole and entire.
From these considerations it is plain that they are wrong in saying that pleasure is a motion or a coming into being. For these terms are not applied to every thing, but only to those things that are divisible into parts and are not wholes. We cannot speak of the coming into being of vision, or of a mathematical poi