Aristotle, Nicomachean Ethics
H. Rackham, Ed.

Activities then are affected in opposite ways by the pleasures and the pains that belong to them, that is to say, those that are intrinsically due to their exercise. Alien pleasures, as has been said, have very much the same effect as pain, for they destroy an activity, only not to the same degree. [6]

Again, since activities differ in moral value, and some are to be adopted, others to be avoided, and others again are neutral, the same is true also of their pleasures: for each activity has a pleasure of its own. Thus the pleasure of a good activity is morally good, that of a bad one morally bad; for even desires for noble things are praised and desires for base things blamed; but the pleasures contained in our activities are more intimately connected with them than the appetites which prompt them, for the appetite is both separate in time and distinct in its nature from the activity, whereas the pleasure is closely linked to the activity, indeed so inseparable from it as to raise a doubt whether the activity is not the same thing as the pleasure. [7] However, we must not regard pleasure as really being a thought or a sensation—indeed this is absurd, though because they are inseparable they seem to some people to be the same.

As then activities are diverse, so also are their pleasures.