PhilosophyQuotes:

"The poet is like a painter who, as we have already observed, will make a likeness of a cobbler though he understands nothing of cobbling; and his picture is good enough for those who know no more than he does, and judge only by colors and figures."

"...the excellence or beauty or truth of every structure, animate or inanimate, and of every action of man, is relative to the use for which nature or the artist has intended them."

"...the imitative poet who aims at being popular is not by nature made, nor is his art intended, to please or to affect the rational principle in the soul; but he will prefer the passionate and fitful temper, which is easily imitated."

- Plato, The Republic

Plato's Republic is available online at Amazon.com.