Aristotle's Poetics is a foundational work of literary theory and criticism that explores the principles and nature of poetry, specifically focusing on drama and tragedy.

Aristotle also said tragedy is composed of six parts-- plot, character, diction, thought, spectacle, and song. They're important pretty much in that order, although he does say that song matters ...

Aristotle’s original text comprised close studies of both tragedy and comedy, with asides on the “Iliad,” “Odyssey” and other examples of epic poetry (a form he judged inferior to tragedy).