An episode is the whole of that part of a tragedy which falls between whole choral songs.
An exode is the whole of that part of a tragedy which is not followed by a song of the chorus.
A parode is the whole of the first utterance of the chorus.
A stasimon is a choral song without anapaests or trochaics. [Note]
A commos is a song of lament shared by the chorus and the actors on the stage.
The constituent parts to be used as ingredients of tragedy have been described above; these are the separable members into which it is quantitatively divided. [Note]
Following upon what has been said above we should next state what ought to be aimed at and what avoided in the construction of a plot, and the means by which the object of tragedy may be achieved.
Since then the structure of the best tragedy should be not simple but complex [Note] and one that represents incidents arousing fear and pity—for that is peculiar to this form of art—it is obvious to begin with that one should not show worthy men passing from good fortune to bad. That does not arouse fear or pity but shocks our feelings.
Nor again wicked people passing from bad fortune to good. That is the most untragic of all, having none of the requisite qualities, since it does not satisfy our feelings [Note] or arouse pity or fear.