Aristotle, Nicomachean Ethics
H. Rackham, Ed.

Sight excels touch in purity, and hearing and smell excel taste; and similarly the pleasures of the intellect excel in purity the pleasures of sensation, while the pleasures of either class differ among themselves in purity. [8]

And it is thought that every animal has its own special pleasure, just as it has its own special function: namely, the pleasure of exercising that function. This will also appear if we consider the different animals one by one: the horse, the dog, man, have different pleasures—as Heracleitus says, an ass would prefer chaff to gold, since to asses food gives more pleasure than gold. Different species therefore have different kinds of pleasures. On the other hand it might be supposed that there is no variety among the pleasures of the same species. [9] But as a matter of fact in the human species at all events there is a great diversity of pleasures. The same things delight some men and annoy others, and things painful and disgusting to some are pleasant and attractive to others. This also holds good of things sweet to the taste: the same things do not taste sweet to a man in a fever as to one in good health; nor does the same temperature feel warm to an invalid and to a person of robust constitution. The same holds good of other things as well. [10]

But we hold that in all such cases the thing really is what it appears to be to the good man. And if this rule is sound, as it is generally held to be, and if the standard of everything is goodness, or the good man, qua good, then the things that seem to him to be pleasures are pleasures, and the things he enjoys are pleasant.