What is the main conflict in Theatre of the Oppressed by Augusto Boal?

In "Theater of the Oppressed", Augusto Boal argues that theater is inherently political and that traditional, Aristotelian theater is inherently oppressive. He reviews the history of theater, from Aristotle through Machiavelli, Hegel, and Brecht, and proposes a new idea of theater that breaks the bounds between audience and performers, and between chorus and protagonist.