Infinitely many mathematicians walk into a bar.

Infinitely many mathematicians walk into a bar.

The first says, “I’ll have a beer.”

The second says, “I’ll have half a beer.”

The third says, “I’ll have a quarter of a beer.”

Before anyone else can speak, the barman fills up exactly two glasses of beer and serves them. “Come on, now,” he says to the group, “You guys have got to learn your limits.”