# My 20 favorite math jokes

I hope my readers don’t mind, but I’ve been writing serious math posts here for ten years so I think it’s high time I inserted some humour onto this blog. Rest assured, serious math posts won’t go away.

Without adieu, my 20 favourite math jokes. Most of them I heard elsewhere, and a few I invented myself.

Why did the chicken cross the Mobius strip?

To get to the other…uh…

Two constants were found to be having an argument:
i: Be rational.
$\pi$: Get real!

Old Macdonald had a form, $e_i\wedge e_i = 0$.

You might be a mathematician if you think fog is a composition.

Professor: Give an example of a vector space.

Student: V.

From the obituary of Samuel Eilenberg:

When someone once asked Professor Eilenberg if he could eat Chinese food with three chopsticks, he answered, “Of course,” according to
Professor Morgan. The questioner asked, “How are you going to do it?”
and Professor Eilenberg replied, “I’ll take the three chopsticks, I’ll
put one of them aside on the table, and I’ll use the other two.”

Let $\epsilon < 0$.

A coconut is just a nut.

Theorem: there exists infinitely many composite numbers.

Proof: suppose there are only finitely many, and multiply them together.

What is green and homeomophic to the open unit interval?

Why can’t you grow corn in Z/4Z?

Answer: because it is not a field.

Where did $x/(x+1)$ go when it got sick in calculus class?

What’s purple and commutes?

How did the analytic number theorist keep warm all winter?

Why did Emil Artin’s necklace keep falling off?

What’s yellow and equivalent to the axiom of choice?

What is a pirate’s favourite measure?

How did a matrix end its argument with its transpose?

Why did the alien fail in proving Fermat’s last theorem?

Answer: the Martian was too small to contain it.

Why did the injective function not enjoy the movie theatre?