The following is a narrative joke told to me by a friend, informally called ‘The Professor of Logic.’ On asking me if I had heard it, which I hadn’t, he insisted on telling it.
He proceeded to tell it as such:
“This guy Chuck goes over to his neighbor, who’s just moved in. He tells him the usual,
“Hi, just wanted to welcome you to the neighborhood, what’s your name?”
The guy’s like “Hi, I’m Jerry.”
Eventually they get to what they do. Chuck goes “I’m a plumber.”
The other guy says he’s a professor of logic at a university.
Chuck asks him,
“What do you teach?”
“I’m a professor of logic.”
“What do you mean by that?”
And the professor says,
“Let me give you an example. Do you have a doghouse?”
“Uh, yeah.”
“Well, then I’d assume you have a dog.”
“Yeah.”
“Well, you know, when dogs have dog houses, and they live in them, that means you have a few kids, and it’s theirs and they take care of it.”
“I do have kids. Two of ‘em actually.”
“Alright, you got kids. That usually means you’re married. To a woman, in most cases.”
“Yeah, I’m married to a woman.
“Well, then you’re a heterosexual male.”
“I am, that’s right.”
“Now you see. Just by asking you if you have a doghouse, I was able to determine you’re a heterosexual male.”
Chuck just goes, “Wow! That’s unbelievable.” And he leaves, impressed.
The next day, our guy Chuck, the main one, not the professor, he’s hustling to get to the bus stop.
So, he gets there. Sees this guy next to him, he asks him if the bus has already come.
“No, it hasn’t.”
Chuck says oh, guess we’ll just have to wait a few minutes, then.
And, uh, the other guy lights up a cigarette and jokingly says “As soon as I light this cigarette, I bet the bus is gonna show up.”
Sure enough, he lights it, and the bus comes around the corner.
Chuck, amazed again, asks him if he’s a professor of logic. The guy with the cigarette doesn’t know what that means, he asks Chuck to explain.
Chuck doesn’t quite know how, and he says,
“Here, let me give you an example.”
“Sure, what”
“You have a doghouse?”
“No.”
“Oh, you must be one of them gays!”
This joke is interesting in its mix of initially intriguing intelligence (regarding the professor of logic’s deductive reasoning) that is later subverted by the stupidity of a person who has completely misinterpreted the meaning of what he’s learned, made only clear with the last line. Given its relative lengthiness in needing to be told over the course of one or two full minutes, the building leading into the final punchline is provided a greater level of anticipation given the relative lack of humorous bits leading up to it. This serves to create a complex, but highly example of a classic punchline-based joke where the sum of the humor is comprised of an ending that only works as a result of the lines that come before it.