Aristotle, Poetics

[1449b] [1] Indeed it is only quite late in its history¹ that the archon granted a chorus for a comic poet; before that they were volunteers.² Comedy had already taken certain forms before there is any mention of those who are called its poets. Who introduced masks or prologues, the number of actors, and so on, is not known. Plot making [Epicharmus and Phormis]³ originally came from Sicily, and of the Athenian poets Crates⁴ was the first to give up the lampooning form and to generalize his dialogue and plots.

Epic poetry agreed with tragedy only in so far as it was a metrical representation of heroic action, but inasmuch as it has a single metre and is narrative in that respect they are different. And then as regards length, tragedy tends to fall within a single revolution of the sun or slightly to exceed that, whereas epic is unlimited in point of time; and that is another difference, although originally the practice was the same in tragedy as in epic poetry.

The constituent parts are some of them the same and some peculiar to tragedy. Consequently any one who knows about tragedy, good and bad, knows about epics too, since tragedy has all the elements of epic poetry, though the elements of tragedy are not all present in the epic.

[20] With the representation of life in hexameter verse⁵ and with comedy we will deal later. We must now treat of tragedy after first gathering up the definition of its nature which results from what we have said already. Tragedy is, then, a representation of an action⁶ that is heroic and complete and of a certain magnitude—by means of language enriched with all kinds of ornament, each used separately in the different parts of the play: it represents men in action and does not use narrative, and through pity and fear it effects relief to these and similar emotions.⁷ By "language enriched" I mean that which has rhythm and tune, i.e., song, and by "the kinds separately" I mean that some effects are produced by verse alone and some again by song.

Since the representation is performed by living persons, it follows at once that one essential part of a tragedy is the spectacular effect, and, besides that, song-making and diction. For these are the means of the representation. By "diction" I mean here the metrical arrangement of the words; and "song making" I use in the full, obvious sense of the word. And since tragedy represents action and is acted by living persons, who must of necessity have certain qualities of character and thought—for it is these which determine the quality of an action;