Adultery is the application of democracy to love.

Mencken’s epigram treats adultery as a kind of “popular sovereignty” in the realm of intimacy: instead of love being governed by a single exclusive bond (a marital “monarchy”), it becomes subject to choice, competition, and shifting consent among multiple parties. The joke depends on a deliberately cynical analogy—democracy as rule by many, applied to a domain culturally policed by exclusivity. Mencken’s broader satirical project often punctured bourgeois moral certainties and exposed the gap between public virtue and private behavior; here, he compresses that critique into a single paradox. The line also implies that romantic fidelity is less a natural law than a social arrangement—one that can be “voted against” by desire.