Top Ten Math Jokes:

What did zero say to eight? Nice belt.

Why was six afraid of seven? Because seven, eight, nine.

Let epsilon be negative.

There are three kinds of people in the world - those who can count and those who can’t.

What is yellow and equivalent to the Axiom of Choice? Zorn’s Lemma.

What is purple and commutes? An abelian grape.

A topologist is someone who cannot tell a doughnut from a coffee mug.

A mathematician is a machine for turning coffee into theorems. (attributed to Paul Erdos)

Why did the mathematician name his dog "Cauchy"? Because the dog left a residue at every pole.

An astronomer, a physicist and a mathematician were holidaying in Scotland. Glancing from a train window, they observed a black sheep in the middle of a field. "How interesting," observed the astronomer, "all Scottish sheep are black!" To which the physicist responded, "No, no! Some Scottish sheep are black!" The mathematician gazed heavenward in supplication, and then intoned, "In Scotland there exists at least one field, containing at least one sheep, at least one side of which is black." (attributed to Ian Stewart)

E to the x is walking down the street when a crowd of functions comes running by. “Run for your life,” they say. “The differential operator is coming!” Unperturbed, e to the x continues walking. Another crowd of functions passes by with the same warning. “The differential operator is coming!” “Can’t hurt me,” thought e to the x, “I am my own derivative.” Then, from around the corner comes the differential operator. Stomp, stomp, stomp. “Why aren’t you running like the others?” asked the differential operator. “You can’t hurt me,” said e to the x, “I am my own derivative!” “Ah,” said the differential operator, “but I am the derivative with respect to y!”

An investment firm is hiring mathematicians. After the first round of interviews, three hopeful recent graduates - a pure mathematician, an applied mathematician, and a graduate in mathematical finance - are asked what starting salary they are expecting. The pure mathematician: "Would $40,000 be too much?" The applied mathematician: "I think $60,000 would be OK." The math finance person: "What about $400,000?" The personnel officer is flabbergasted: "Do you know that we have a graduate in pure mathematics who is willing to do the same work for a tenth of what you are demanding!?" "Well, I thought of $180,000 for me, $180,000 for you - and $40,000 for the pure mathematician who will do all the work.

. . . but this one goes to eleven. . .