Simple and complex plots

Plots are either simple or complex, reflecting the nature of the actions they imitate. A simple action is one that is continuous and unified, in which the change of fortune comes about without reversal of situation or recognition. A complex action is one in which the change is accompanied by a reversal of situation, or a recognition, or both. These elements must arise from the internal structure of the plot itself — what follows must be the necessary or probable consequence of the preceding actions.

This is an important qualification: reversal and recognition are not mere theatrical devices applied from the outside. They must emerge from the causal logic of the plot, so that when they occur they feel simultaneously surprising and inevitable. A reversal or recognition that is merely attached to a plot from outside — engineered by the playwright without arising from the action itself — is inferior to one that is latent in the situation from the beginning and discovered in the course of the action. The complex plot, properly constructed, is the higher form.