I could quote RS Crane all day (Languages of Criticism and the Structure of Poetry). In one passage, he talks about how, with Aristotle anyway, it's useless to consider "pleasure" in the abstract, as an "end" or purpose of poetry. Pleasure is always conjoined with particular forms of activity, and is characterized by them. Then, in a paragraph, he telescopes the historical development of mimetic poetry, from basic human pleasure in imitations & mimicry, to the moral distinction between imitation of things admired ("better people") and things satirized ("worse peope"), to the practice of a Homer, in which a complete, integral form has been found to subsume many forms of imitation:

"...finally to have eventuated, with Homer, in self-contained works of art the final cause of which is beauty rather than either the general pleasurableness or the moral utility of imitations... It is indeed a final end in two important senses - in the sense that it is an end peculiar to the poetic art rather than one imitative poetry shares with other arts or activities, and also in the sense that it subsumes the other ends of pleasing and instructing, and goes beyond them. For it is distinctive of poetry such as Homer's that it utilizes the pleasure we all take in imitation and rhythm, and the vivid interest we have in other human beings and especially in the moral issues in which they can be involved, in order to make objects which we can continue to appreciate, after our first curiosity is satisfied, for the sake of their intrinsic rightness and beauty. This therefore is where poetic theory, in its normative aspect, in general must begin..." (pp. 64-65)