What do you get when you cross scholarly research and dick jokes? Nothing to laugh at, normally. But science writer Jim Holt defies the Heisenberg principle of humor — you can't study it without killing it — in his book Stop Me If You've Heard This: A History and Philosophy of Jokes. We caught up with him walking into a bar.

Wired: One question you tackle is who invented the joke. Weren't we cracking wise back in the caves?

Holt: No, the classic joke form — setup with incongruity, punch line that resolves the incongruity —seems to have come out of Greece and Rome. There's this guy in Greek -mythology called Palamedes who invented practically everything — numbers, currency, lighthouses, breakfast, lunch, and dinner. He also supposedly invented the joke. And, of course, he was stoned to death.

Wired: So where do new jokes come from?

Holt: It used to be that all the jokes I got came from Wall Street. Now, with the Internet, they're sort of everywhere and nowhere at once. But the ideas for jokes are cultural — concepts that keep reappearing in different guises over the centuries.

Wired: There are lots of theories about why we joke. Which do you find most plausible?

Holt: Well, there's the superiority theory, that jokes express scorn for your inferiors — cripples and cuckolds and foreigners and the like. Plato said we laugh at vice. Then there's the Freudian interpretation, that it's all about sexual repression. Finally, there's the seduction theory, based on the observation that men do most of the joking while women do most of the laughing. Christopher Hitchens wrote a piece in Vanity Fair arguing that the only way most guys can impress women is to make them laugh.

Wired: But your favorite explanation is a mashup of Kant and evolutionary biology, right?

Holt: V. S. Ramachandran, the brain researcher, has a theory about the origin of laughter — that when you're in the jungle and there's an apparent threat, the first member of the kinship group to notice that it's not a real threat emits this stereotyped vocalization. And it's contagious, so everyone starts laughing. That's also the basis of the relief theory of humor, that there's a release of the energy you had summoned up to solve some puzzle. Kant said that the essence of humor is a strained expectation dissolving into nothing.

Wired: Did you find any candidates for the perfect joke?

Holt: I did find what might be the shortest possible joke: "Pretentious? Moi?"

1965: An astronaut in space holds a conversation with an aquanaut underwater, marking another milestone in human communication.

Astronaut Gordon Cooper, orbiting the Earth with Pete Conrad in Gemini 5, hooked up by radiotelephone with an old pal, astronaut-turned-aquanaut Scott Carpenter, who was living and working 205 feet beneath the surface of the Pacific Ocean near La Jolla, California, aboard Sealab II.

The two men had known each other since 1959, when they were among the seven pilots chosen by NASA to be America's first Project Mercury astronauts. Carpenter, a former Navy pilot, had already been in space, the solo astronaut on a mistake-plagued, three-orbit flight aboard Aurora 7 that resulted in his being effectively grounded.

He was on leave from the space agency when he joined the Navy's Sealab II project as training officer. Carpenter eventually resigned from NASA in 1967. He retired from the Navy in 1969.

Cooper and Conrad, meanwhile, were nearing the end of an eight-day orbital mission to test human endurance in space. Eight days was recognized as the time needed to travel to the moon and back. (Five days was the longest Soviet space flight before then, and the American record was four days. By years' end, American astronauts would complete a 14-day mission in space.)

The radio hookup was partly a gimmick, to take advantage of Carpenter's astronaut status to publicize the Sealab II project. But it was also a method of testing the effectiveness of an underwater electronics lab installed aboard the submersible.

Gemini 5 was not the only long-distance call made from Sealab II. The Navy aquanauts also spoke with President Johnson at the White House and with Jacques Cousteau's Conshelf 3 team, French colleagues conducting a similar underwater-habitat test off Cap Ferrat in the Mediterranean Sea.

Following their chat with Carpenter, Cooper and Conrad readied Gemini 5 for its return to Earth and splashed down in the very same Pacific Ocean later that day.

Thirty years later, in 1995, Carpenter recreated his seabed-to-space call, chatting with astronauts aboard the space shuttle Endeavor while staying at Jules' Undersea Lodge off Key Largo, Florida.

Source: Various

BLACK ROCK CITY, Nevada -- Wild rides, fireworks and letting it all hang out. That's the updated American dream at Burning Man 2008.

The annual desert gathering always celebrates that most-American ideal: freedom. Freedom to ride a giant red, white and blue tricycle across the playa; freedom to blow your mind however you want; freedom to traipse around wearing nothing but body paint.

That kind of ingrained whimsy, rather than politics, seems to be the point of this year's American Dream art theme at Burning Man. "What has America achieved that you admire?" is the event's official statement. "What has it done or failed to do that fills you with dismay? What is laudable? What is ludicrous?"

Groovy, man. Let's get it on.

Left: Red, white and blue abounds at the festival this year.

Red, white and blue abounds at the festival this year.

A stagecoach rolls up the esplanade on Tuesday evening.

Duane Flatmo from Eureka, California, steers his fire-breathing dragon around the esplanade Tuesday.

After hunkering down during Monday's sandstorm, burners break out their colorful costumes Tuesday -- including some that are just painted on. Robin Bowles, right, and her friend Cowboy Curtis chill on the playa on a "fuzzy bunny." The Man can be seen far off in the distance on the left.

A group of burners break out a desert "boat" to parade across the playa.

Black Rock City is humming Thursday.

Lamp Lighters walk down the esplanade Tuesday.

A panel van decked out with a lit-up Golden Gate Bridge makes its way across the sand Tuesday.

Tutu-wearing burner Diana Zanelli of Texas delights in the swirl of lights from inside artist Crispell Wagner's "modern version of the dream machine," an interactive piece of light art.

Home is where the art is at Burning Man.

The Man glows with neon as Helen Corley from San Ramon, California, twirls her flow lights below the festival's namesake icon in Black Rock City.

A giant duck lights up the night Tuesday as it rolls across the dusty desert floor.