The objective of Brecht's Lehrstücke was that they be taken on tour and performed in schools or in factories to educate the masses about socialist politics.
It tells the story of a rich merchant, who must cross the fictional Yahi Desert to close an oil deal.
During the trip the class differences between him and his working-class porter (or "coolie" as he is called in most English-language editions) are shown.
Brecht intends to show the coolie as a victim caught in the gears of the merciless logic of class warfare.
He hanshan ("The Confronted undershirt"), a Yuan Dynasty-era Chinese play, was the model for The Exception and the Rule.