Aristotle's Poetics is the earliest surviving work of dramatic theory and the first extant philosophical treatise on literary theory. The philosopher presents a treatise on what he defines as poetry, which includes verse drama, the satyr play, lyric poetry, and epic poetry. They are different in three ways that Aristotle describes thus: in music rhythm, harmony, meter, and melody; in the difference of goodness in the characters; in how the narrative is presented - telling a story or acting it out. He identifies two first principles in poetics: imitation and genres. The work includes a detailed examination of tragedy in five parts: definition, the rules for its construction, possible criticisms of an epic or tragedy, and the answers to them, and tragedy as artistically superior to epic poetry.