Math Jokes

Here are some goofy math jokes. Note: I preserved the attributions I received with these jokes, but it is likely these are simply the last people who passed them on, not original authors. For more serious thoughts, try my mathematical quotations page.
External links:
Happy Face to the power of -1 is upside-down Happy Face
Happy Face Math by Charlie Smith.

Matrix Rotation
Matrix Rotation from xkcd.
xkcd is a webcomic by Randall Monroe.
  1. Three logicians walk into a bar. The bartender asks, “Would you all like something to drink?” The first logician says, “I do not know.” The second logician says, “I do not know.” The third logician says, “Yes.”

  2. Three logicians walk into a bar. The bartender asks, “Would you all like something to drink?” The first logician says, “I do not know.” The second logician says, “I do not know.” The third logician says, “No.” Luckily, the bartender is also a logician, so he serves two beers.
    From Reddit user whatkindofred

  3. A topologist goes to a store and sees a sign on the door saying “Sorry, we’re closed”. They knock on the door and eventually someone opens it, annoyed, and says “Read the sign!”. The topologist replies, “I did, but I don’t know if you’re open or not!”
    From Reddit user Mowtom_

  4. This one has always been my favorite. Why can’t you plant corn in Z/6Z? Because it’s not a field! Okay, but why can’t you plant corn in Z/5Z? Because it’s an abstract mathematical object!
    From Reddit user MathManiac5772

  5. A math student is told by his mother to set the table. “To what?” he replies.
    From Keith Raskin

  6. I went to see Plane Meets Plane, but there was a long line.
    From Keith Raskin

  7. Q: How many mathematicians does it take to change a lightbulb?
    A: On average or do you want the whole distribution?
    From Keith Raskin

  8. Customer: “How much is a large order of Fibonaccos?”
    Cashier: “It’s the price of a small order plus the price of a medium order.”
    Henry G. Baker (

  9. Zenophobia: the irrational fear of convergent sequences.
    Mike Taylor (

  10. There really are only two types of people in the world, those that don’t do math, and those that take care of them.
    Larry James (

  11. A physicist, a biologist, and a mathematician are sitting in a café and notice people going into and coming out of the house across the street. First they see two people going into the house. Time passes. After a while, they notice three persons coming out of the house.
    The physicist: “The measurement was not accurate.”
    The biologist: “They have reproduced.”
    The mathematician: “If one person enters the house, then it will be empty again.”

  12. An engineer, a physicist and a mathematician find themselves in an anecdote, indeed an anecdote quite similar to many that you have no doubt already heard. After some observations and rough calculations, the engineer realizes the situation and starts laughing. A few minutes later, the physicist understands too and chuckles to himself happily as he now has enough experimental evidence to publish a paper. This leaves the mathematician somewhat perplexed, as he had observed right away that he was the subject of an anecdote, and deduced quite rapidly the presence of humor from similar anecdotes, but considers this anecdote to be too trivial a corollary to be significant, let alone funny.
    Forwarded to me by Phil Freed.

  13. Q: What is the physicist’s definition of a vector space?
    A: A set V such that for any x in V, x has a little arrow drawn over it.
    Snis Pilbor (

  14. A farmer discovered his horse was extraordinarily intelligent. You could ask it an arithmetic problem, and it would tap out the answer with a hoof. Researchers were fascinated and tested the horse. They discovered the horse understood algebra, Euclidean geometry, calculus, and even group theory. However, when they gave the horse problems with Cartesian coordinates, it just stood there dumbly, like any horse. This was quite surprising, given how intelligent the horse was otherwise. They brought in an expert who examined the situation and explained the problem: “Of course the horse cannot understand any Cartesian coordinates you show it. You are putting Descartes before the horse.”

  15. ex and a constant were walking down the street. Suddenly, the constant notices a differential operator walking along the other side of the street. “Oh, no!” exclaims the constant. “I’ve got to run away! You’ve got to hide me! There’s a differential operator… he could reduce me to nothing!” “Hmmmph,” came the haughty reply. “I’m ex. He can’t do anything to me.” So ex walked across the street and introduced himself. “Hi. How are you doing? I am ex,” he bragged. “Pleased to meet you,” replied the differential operator. “I’m d/dy.”
    Forwarded to me by Phil Freed.

  16. Never say “N factorial,” simply scream “N” at the top of your lungs.
    Mark David Biesiada (

  17. Theorem: Consider the set of all sets that have never been considered. Hey! They’re all gone! Oh, well, never mind…
    Dr. David Batchelor (

  18. What polygon is also a card trick? Decagon.
    From Keith Raskin

  19. One of my undergrad professors was asked what kind of problems would be on the final. His answer: “Just study the old tests. The problems will be be the same, just the numbers will be different. But not all the numbers will be different. Pi will be the same. Planck’s constant will be the same…”
    Kurt Jaeger (

  20. Expand (a+b)^n.
        (a + b) ^ n
      (a  +  b)  ^  n
    (a   +   b)   ^   n
    et cetera.
    Zdislav V. Kovarik (kovarik@mcmail.cis.McMaster.CA).

  21. Another professor, when asked how many problems there would be on the final, turned to the student and replied, “I think you will have lots of problems on the final.”
    Kurt Jaeger (

  22. Philosophy is a game with objectives and no rules.
    Mathematics is a game with rules and no objectives.
    Ian Ellis (

  23. A mathematician, standing puzzled at the photocopier and complaining to the secretary: “I set it to ‘Single Sided Copy,’ and now it comes out as a Möbius Strip!”
    Originally a cartoon in the American Mathematical Monthly, via Hauke Reddman (

Compilation © copyright 2000 by Eric Postpischil.