Since 1980 a number of philosophers have explored the psychology, aesthetics, and ethics of humor. The incongruity theory dominates though, as in earlier theorizing, the precise relation of humor to incongruity is seldom made clear. Not just any experience of incongruity constitutes humor. Coming home to find one's family murdered would be incongruous but not funny. Even incongruity intended to be humorous may not be funny to everyone. What seems necessary for humorous amusement is that the incongruity be enjoyed.

The enjoyment of incongruity is not sufficient for amusement, however, for one may enjoy something bizarre or fantastic for its incongruity without being amused. Some people also enjoy grotesque and macabre works of art and horror movies and novels in part for their incongruity. In aesthetics there is no general agreement on what distinguishes amusement from such cases; one suggestion is that in amusement we tend to...