An infinite crowd of mathematicians entered a bar. The first ordered a pint of ale. The second ordered a half pint. The third ordered a quarter pint.
“I get it,” said the bartender, and poured two pints.
Q: What do you get if you divide the circumference of a jack-o-lantern by its diameter?
A: Pumpkin Pi!
One evening Rene Descartes went to relax at a local tavern. The tender approached and said, “Ah, good evening Monsieur Descartes! Shall I serve you the usual drink?”. Descartes replied, “I think not.”, and promptly vanished.
Algebraic symbols are used when you do not know what you are talking about.