A quotation, like a pun, should come unsought, and then be welcomed only for some propriety of felicity justifying the intrusion.

Chapman likens quotations to puns: both are rhetorical intrusions that can feel showy or forced if introduced deliberately. The ideal quotation, he suggests, should arise naturally from the writer’s or speaker’s thought rather than being hunted down to decorate an argument. Even when it does “intrude,” it deserves acceptance only if it has a clear fitness—what he calls a “propriety of felicity”: an aptness, grace, or happy precision that genuinely advances meaning or pleasure. The remark is also a quiet warning against pedantry and name-dropping, urging restraint and organic integration of borrowed words into one’s own discourse.