Of all the absurd things that foreigners have said about the Japanese, the assertion that they are lacking in a sense of humor takes the cake.
As anyone with their wits even slightly about them knows, the Japanese do surely have a subtle, sophisticated and rollicking sense of humor. The only trouble is, they so rarely display it that it's about as hard to find as a copy of the Torah in a Ukrainian convent.
In fact, the Japanese are laughing as much as the rest of us — they're just doing it to themselves.