I feel attempted to apologize for linking to a Wikipedia entry. I use it to learn something that I know little or nothing about - if I read the entry I actually know something about, I tend to nitpick. But we should take note of the Muses as invoked by Hesiod, Homer, and countless classical, medieval, and renaissance poets following them. But I got to thinking about the work performed by poetry in the days of Hesiod and Homer: that it was not primarily art for art's sake, for aesthetic pleasure (though doubtless it gave pleasure). The techne of rhythm, meter, and rhyme (though rhyme was not a main feature of the Greek and Latin hexameters) are of course techniques to aid memory. In a primary oral culture as pre-Athenian Greece was, people develop their memories to degrees that we would find astounding. The Muses are the progeny of Zeus and Mnemosyne (memory), according to Hesiod, and his invocation of them implies of course divine inspiration - being subject to the power of the god and the Muses as he sings.
We will learn more about how oral-formulaic poetry works when we read Knox's Introduction to The Odyssey. But it's important to underline the fact that arts and their Muses have their roots in utility and memory.