His wit invites you by his looks to come,
But when you knock it never is at home.

Cowper’s couplet satirizes a person whose appearance promises lively intelligence (“wit”) but whose conversation proves empty or inaccessible. The “looks” act like an invitation—suggesting sparkle, readiness, and social ease—yet the moment one tries to engage (“knock”), nothing answers: the wit is “never … at home.” The image borrows from the etiquette of visiting, turning social interaction into a comic scene of a caller left at a closed door. More broadly, it warns against judging mental substance by outward charm and hints at the gap between reputation or style and genuine intellectual presence.