The most efficient water power in the world - women’s tears.

Mizner’s line is a cynical epigram that treats “women’s tears” as a kind of irresistible force—more effective than literal water power at driving outcomes. The joke depends on a metaphor from industry and engineering (water power as efficient energy) applied to social and romantic life, implying that displays of female emotion can compel men’s sympathy, guilt, or compliance. Read historically, it reflects early-20th-century gender stereotypes and a hard-boiled, theatrical wit associated with Mizner’s persona: the bon mot that punctures sentiment by recasting it as leverage. The quote’s sting lies in its reduction of emotion to instrumentality, inviting readers to laugh while also revealing the speaker’s distrust of sincerity.