From a well-respected Theravadin monk:
For many of us, the most difficult part of practicing right speech lies in how we express our sense of humor. Especially here in America, we’re used to getting laughs with exaggeration, sarcasm, group stereotypes, and pure silliness — all classic examples of wrong speech. If people get used to these sorts of careless humor, they stop listening carefully to what we say. In this way, we cheapen our own discourse. Actually, there’s enough irony in the state of the world that we don’t need to exaggerate or be sarcastic. The greatest humorists are the ones who simply make us look directly at the way things are.
Expressing our humor in ways that are truthful, useful, and wise may require thought and effort, but when we master this sort of wit we find that the effort is well spent. We’ve sharpened our own minds and have improved our verbal environment. In this way, even our jokes become part of our practice: an opportunity to develop positive qualities of mind and to offer something of intelligent value to the people around us.
(from Right Speech by Thanissaro Bhikkhu available at http://www.accesstoinsight.org/lib/authors/thanissaro/speech.html)
Unfortunately, Ven. Thanissaro doesn’t give us an example of the wholesome humor he describes. I know it when I see it, but it’s hard to invent a story or joke without a context. This, from the New Yorker dated 25 April 2011 (p.56), caught my fancy: When Eagleman was a boy, his favorite joke had a turtle walking into a sheriff’s office. “I’ve just been attacked by three snails!” he shouts. “Tell me what happened,” the sheriff replies. “I don’t know, it all happened so fast.”
Perhaps this just proves that context is important. The article quoted is called “The Possibilian: What a brush with death taught David Eagleman about the mysteries of time and the brain.” Anytime we have points of reference in common with others, more subtle humor is possible. “In” jokes tend to be the funniest, since they reflect our ideas about ourselves.
The main point is that a lot of our humor can be mean. This is challenging, because we all like to be around people who are funny, and we like to be liked, so, if we can, we like to be funny. We can do it without putting others down or assuming a sarcastic attitude, but it takes some attention.