Pleasure's sake of Pleasure for Life's sake; because these two plainly are closely connected and admit not of separation; since Pleasure comes not into being without Working, and again, every Working Pleasure perfects.)
V
And this is one reason why Pleasures are thought to differ in kind, because we suppose that things which differ in kind must be perfected by things so differing: it plainly being the case with the productions of Nature and Art; as animals, and trees, and pictures, and statues, and houses, and furniture; and so we suppose that in like manner acts of Working which are different in kind are perfected by things differing in kind. Now Intellectual Workings differ specifically from those of the Senses, and these last from one another; therefore so do the Pleasures which perfect them.
This may be shown also from the intimate connection subsisting between each Pleasure and the Working which it perfects: I mean, that the Pleasure proper to any Working increases that Working; for they who work with Pleasure sift all things more closely and carry them out to a greater degree of nicety; for instance, those men become geometricians who take Pleasure in geometry, and they apprehend particular points more completely: in like manner men who are fond of music, or architecture, or anything else, improve each on his own pursuit, because they feel Pleasure in them. Thus the Pleasures aid in increasing the Workings, and things which do so aid are proper and peculiar: but the things which are proper and peculiar to others specifically different are themselves 1175b also specifically different.
Yet even more clearly may this be shown from the fact that the Pleasures arising from one kind of Workings hinder other Workings; for instance, people who are fond of flute-music cannot keep their attention to conversation or discourse when they catch the sound of a flute; because they take more Pleasure in flute-playing than in the Working they are at the time engaged on; in other words, the Pleasure attendant on flute-playing destroys the Working of conversation or discourse.
