I wanted to start my logic class this semester with a good logic joke. Logic can sometimes feel dull and boring to students, so setting a humorous tone from the start of term can be helpful. So I told them this joke, which is a modified (and more morally and socially acceptable version of another you may know). Feel free to steal it.

Last week a new neighbor moved into the house across from mine. As one does with new neighbors, I went over to meet him and we got to talking. He asked what I did, and I told him I was a professor. When he inquired what I taught, I said, “Logic.”

He was curious and said, “Logic, what’s that?”

“Let me give you an example,” I said. “Do you own a lawnmower?”


“Well, I infer from this that you know how to use your lawnmower.”

“Yeah, that’s right.”

“Well, I infer from this that you learned how to use your lawnmower by reading the instruction manual.”

“Right again.”

“So then I can infer that you know how to read.”

“Of course.”

“There you go. That’s logic.”

My new neighbor was impressed. A few days later, he was talking with some old friends when he mentioned that one of his new neighbors was a logic professor. His friend then asked, “Logic, what’s that?”

My neighbor, full of confidence, said, “Let me give you an example. Do you own a lawnmower?”


“What are you, illiterate?”