Foil
Character Role Analysis
Better Argument and Worse Argument
By giving us two characters with names that highlight the stark differences between them, Aristophanes very helpfully points us toward the play's foil pairing before we've even gotten past the cast of characters. Pretty decent of him.
Anyway, Better Argument and Worse Argument represent totally opposite philosophies: Better Argument is all about tradition, respect for your elders, and keeping your body in great shape, while Worse Argument has no such plans—his only goal is to use rhetoric effectively to bring people over to his side, regardless of the morals or consequences involved (or how flabby you get in the process).
The tension between these two schools of thought is at the heart of the play, since the big drama revolves around Strepsiades's intense desire to learn Worse Argument's methods in order to cheat his creditors out of the money they're owed… and then his subsequent realization (when the argument is turned against him) that the newfangled philosophy is bad news.