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I know this is subjective, but the principle "should be of interest to mathematicians" trumps. (I hope.)

closed as off topic by S. Carnahan, Scott Morrison Dec 24 '09 at 2:21

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    I just voted this -1, and I'd like to see the question closed. People have had over a month to enjoy it, and its continued presence on the front page seems to encourage people to post very soft questions. This takes Math Overflow in what I think is a bad direction. – Tom Leinster Nov 28 '09 at 12:34
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    I disagree with Tom. I think some levity is desirable, and MO shouldn't all be serious business. – Richard Dore Dec 10 '09 at 21:50
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    With respect to the title, "No." – Harry Gindi Dec 10 '09 at 22:23
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    I've decided to finally put this one out of its misery. All that's happening now is people add new, mostly lame, jokes at the the end, which no one ever reads, and as a result the question keeps bouncing back to the front page. It's time to die. Closed. – Scott Morrison Dec 24 '09 at 2:23
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    The Pigeonhole Principle: If there are n pigeons and n+1 holes, then at least one pigeon must have at least two holes in it. – Bhaskar Vashishth May 6 '15 at 2:32

80 Answers 80

Abstruse Goose is great for maths and physics jokes.

I first heard this on an episode of the Big Bang Theory, I don't know the origin.

The physicist asks the mathematician: "Why did the chicken cross the road?"

The mathematician ponders a while and then replies: "I have a solution, but it only works for a spherical chicken in a vacuum."

An infinite number of mathematicians walk into a bar. The first one orders a beer, the second one orders half a beer, the third one a quarter of beer and so on. After a while of this happening, the bartender says "Come on guys! So many people and not even a couple of beers??".

Q: What did the threefold blown up at two points say while waiting in a long line for a restroom?

A: I have to pee too.

Ugh, why aren't these posted yet:

Q: What's purple and commutes? A: An Abelian grape.

Q: What's sour, yellow, and equivalent to the axiom of choice? A: Zorn's lemon.


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    What's purple, commutes, and is worshipped twice a night? A bi-nightly venerated Abelian grape. The other answer to "what's purple and commutes?", for the Chicagoans and ex-Chicagoans out there, is "the Evanston Express". – Hugh Thomas Oct 19 '09 at 17:07
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    They are not posted because they are not good, maybe? :P – Mariano Suárez-Álvarez Nov 23 '09 at 5:36
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    Seen on a restroom wall in the Berkeley math dept.: What's brown and commutes? An abelian poop. – S. Carnahan Jun 22 '10 at 7:31
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    Note that these jokes already appear in the very first answer by David Zureick-Brown: mathoverflow.net/a/1085/5340 – Zsbán Ambrus Jul 17 '14 at 17:08

Test to tell the difference between a Physicist or a Mathematician

Consider the following scenario: A room with a sink at the far end with a working cold water faucet plus a table with the following items on top – small bucket, ring stand, Bunsen burner, and a pack of matches. The problem is to boil water.

If the individual picks up the bucket from the table, walks to the sink and fills the bucket from the faucet, brings it back to the table, sets it on the ring stand, puts the Bunsen burner under the stand, and then lights the burner and waits for the water to boil … this establishes the base line but does not separate which it the Physicist and which is the Mathematician.

Test scenario 2: The bucket is now sitting on the floor under the table and the problem is again to boil water.

If the individual picks up the bucket from under the table, walks directly to the sink and fills the bucket from the faucet, brings it back to the table, sets it on the ring stand, puts the Bunsen burner under the stand, and then lights the burner and waits for the water to boil … this proves that this individual is the Physicist.

However, if the individual picks up the bucket from under the table and places it back on top of the table thus reducing the current problem to a form that they have previously solved … this proves that this individual is the Mathematician.

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    There's a sequel to this when the first scenario is putting out fire when the house is burning and the second is when the house is not burning. – Zsbán Ambrus Apr 17 '10 at 22:13
  • There was a simple version: Scenario2: the bucket was filled with water at the beginning. The one who boils it directly was physicist, the one who pours the water out to reduce it to a solved problem was mathematician. – Wilson of Gordon Dec 13 '15 at 10:51

Q: Why was 3 afraid of 5?

A: Because "5 8 13."

(Works better when you actually say it out loud...)

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    I prefer the reductive version "Why was 8 afraid of 8?" – Richard Dore Oct 26 '09 at 15:32
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    Hey, if you do that and allow plurals, then you can make an alternative to the "buffalo buffalo buffalo..." sentences using all 8s. e.g. 8s8s888s (the eights that eights ate, ate eights...) – Elizabeth S. Q. Goodman Nov 20 '09 at 7:21
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    But ‘8’ is already plural! So ‘8 8 8 8 8’ means (or could mean) that eight animals, which eight animals ate, ate eight animals (‘eight eight ate ate eight’). – Toby Bartels Jan 26 '14 at 8:46
  • A similar version, Why is 6 afraid of 7? because 7, 8, 9 – math137 Feb 15 '14 at 13:25
  • And why is $\epsilon$ afraid of $\zeta$? – Goldstern Jul 23 '17 at 19:37

a pure and applied mathematician were sitting in a bar, when they spotted a hot chick 2 meters away. However, this was a weird place where they could take one 1 meter step and each consecutive would have to be half of the length of the previous one.

The pure mathematician was sad because he knew he could never get to the girl. The applied one was happy because he knew that for all practical purposes he can get close enough.

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    The pure mathematician knew he could make the time gap between each step also half of the previous, and get their in a finite amount of time. – Steven Gubkin May 31 '11 at 12:51

Quite a few mathematics / academic jokes here.

For actual humour, rather than simply bad puns, I recommend the books:

  • A Random Walk in Science
  • More Random Walks in Science

As well as the odd bad pun, they also contain many anecdotes demonstrating that scientists (and mathematicians) are also human. A few that have stuck in my memory: just about every "mathematics of big game hunting" method, the various "proof by ...", a (genuine!) article co-authored by a cat, and a disturbing article on refereemanship.

Posterior Analysis: when a statistician looks at the rear end of a member of the appropriate sex.

In a math party, all were having a good time. y was the dj, everybody was Riemmanly drunk. Then, when the x saw e^x on a corner crying, he asked: - Hey e^x, why don't you integrate ? - Because I keep always the same!!!

Check out the book 777 Mathematical Conversation Starters by John de Pillis. The subject of the book is mathematics topics to talk about, but it is also full of interesting quotes, jokes, and cartoons.

If we can formalize the property of "being a good math joke" good enough to construct a Turing Machine that checks it, then I think we can conclude they don't exist.

The reason is that in that case we can construct a Turing Machine (say of length N) that checks each possible string, and stops only if a good math joke was found. The busy beaver function on N establishes an upper bound for the number of strings the machine needs to check until we can conclude that it wouldn't halt (and therefore no good math jokes exist).

Based on empirical evidence, it may be possible that all those cases have already been checked (with negative answer), which implies my thesis.

(I'm being ironical, I like much of the jokes posted in here :P)

A mathematician in a job interview was asked, "We need to see what kind of attitude you have toward problem solving. So tell us, is the glass half empty or half full."

His reply, "It's 1-x."

-William Mauritzen

Q: What's purple and commutes? A: An abelian grape!

After a 1-dimensional collapse, what did the 1-simplex show that new chick from logistics?

As it would be impossible to prove that good math jokes don't exist I would have to say that the probability is better than zero.

12 ? The least integer that symbolizes all integers just by itself. Successors: 123, 1234...

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