Infinite Mathematicians in a Bar

An infinite crowd of mathematicians enter a bar. The first one orders a pint, the second one orders half a pint, the third one orders a quarter pint. The bartender says, "Ok, I get it!" and pours two pints.

Number Scare

Q: Did you here about the mathematician who was afraid of negative numbers?
A: He will stop at nothing to avoid them.

He Is On The Outside

An engineer, a physicist, and a mathematician are trying to set up a fenced- in area for some sheep, but they have a limited amount of building material. The engineer gets up first and makes a square fence with the material, reasoning that it's a pretty good working solution. "No no," says the physicist, "there's a better way." He takes the fence and makes a circular pen, showing how it encompasses the maximum possible space with the given material. Then the mathematician speaks up: "No, no, there's an even better way." To the others' amusement he proceeds to construct a little tiny fence around himself, then declares: "I define myself to be on the outside."