“We laugh when Moe hits Larry because we know that Larry’s not really being hurt,” says McGraw, referring to humorous slapstick. “It’s a violation of social norms. You don’t hit people, especially a friend. But it’s okay because it’s not real.” He points out a recent example, an internet video of a chain-smoking Indonesian toddler. “When I was first told about that, I laughed, because it seems unreal—what parent would let their kids smoke cigarettes? The fact that the situation seemed unbelievable made it benign. Then when I saw the video of this kid smoking, it was no longer possible to laugh about it.”

McGraw thinks the theory works for other kinds of humor, like puns, which break a linguistic convention or rule but are still okay because they adhere to another rule, so the sentence still makes sense. It also explains why dramas and action movies play better outside of their home countries than comedies do. “It’s hard to find a comedy that’s funny cross-culturally because the ways that violations can be benign differ from culture to culture. The comedy that is funny cross-culturally tends to involve a lot of physical humor. The violations are clear no matter who you are,” he says.