Deductive Reasoning (For Arlin)

Arlin is quite the critical thinker and analyst - so I thought he'd get a kick out of this one: 

John is mowing his lawn when he sees a new neighbor moving in. He stops and steps to the fence to see what the new neighbor is like. After calling him over, the new neighbor, Bob, tells says that he is a Professor of Deductive Reasoning at the college.

John- Deductive Reasoning? What's that?

Bob- Well, lemme give you an example. I see you have a doghouse. That leads me to believe you have a dog. If you have a dog, perhaps you have children. If you have children, then I would deduce that you have a wife. By having a wife, you are enforcing that you are a heterosexual.

John- That's pretty neat!

They part ways and John goes to talk to another neighbor, Jerry, who is watching the move.

Jerry- New neighbor, huh? What's he do?

John- He's a Professor of Deductive Reasoning at the college.

Jerry- Deductive Reasoning? What's that?

John- Lemme give you an example. Do you have a dog?

Jerry- No, I don't.

John- Fag!