What is the main theme of The Threepenny Opera?
Generally, the main themes are corruption, vice (or sin), and redemption. These are themes that can be linked to human behavior generally and to specific characters' behavior. But overall, Brecht is also exploring ideas of love and loyalty, as well as the gullibility of men and women in love. Also, anti-heroism is a string theme: Macheath is a sort of anti-hero; he treats women badly but is charming and charismatic.