Via Arts and Letters Daily..... A Los Angeles Times piece by Jim Holt.
The whole point of humor, Freud thought, is to get around our inhibitions. Most of us in our daily lives expend a certain amount of psychic energy in keeping our sexual impulses at bay. (If we didn't, civilization would be rather a mess.) A naughty joke -- whether verbal or visual -- catches our inner censor off guard and liberates these dangerous impulses, if only for a moment. The result is a discharge of nervous energy through the facial and respiratory muscles: in a word, laughter.
There's a slight problem with this.
If the Freudian view of humor is correct, the people who laugh the hardest at lewd jokes should be those who are the most sexually repressed, because they are the ones who enjoy the greatest release of energy when they are liberated from their inhibitions. But in reality, the opposite seems to be the case. Research by the late British psychologist Hans Eysenck suggests that the people who get the biggest kick out of sexual humor tend to be the ones who are least inhibited about displaying their randy impulses.
There are two other classic theories of humor in competition with his. One of them is the "superiority theory," propounded in various forms by Plato, Thomas Hobbes and Henri Bergson, which says that laughter is a way of crowing victoriously over the humiliation of others. This theory works well at explaining the appeal of ethnic and racial jokes, of jokes about gays and drunkards and henpecked husbands and lawyers and women....
The other time-honored view of humor has a rather sweeter flavor, and a more intellectual one. It is the "incongruity theory," versions of which were held by Blaise Pascal, Immanuel Kant and Arthur Schopenhauer, which says that we laugh when the decorous suddenly dissolves into the absurd. "Do you believe in clubs for small children?" W.C. Fields was once asked. "Only when kindness fails," he replied.
I think the answer is all of the above. But trying to think of a punchline for the unfinished joke mentioned in the article is going to irritate me far more than is healthy.
.....about a resident of Abdera, a Greek town whose citizens were renowned for their foolishness. "Seeing a eunuch, an Abderite asked him how many children he had. The eunuch replied that he had none, because he lacked the means of reproduction. Retorted the Abderite... "