In the new Broadway play “The Country House,” a successful movie director is fighting with his playwright brother-in-law about art and commercialism when he yells, “What an odd pursuit, when you stop to think about it: Grown people shouting in rooms missing a fourth wall!”

The line gets a huge laugh every time. The audience seems to appreciate the self-knowingness of an actor’s complaining about the very same thing he is doing at that moment.

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