Archive for July 14, 2010


When I give presentations, I often display the following slide:

This is what I call a joke grenade: you pull the pin, and it takes about five seconds before any laughter occurs. The delay occurs because the humor is subtle; it takes most folks a few seconds — and it takes some folks a great number of seconds — to realize that the third error is that the sign contains only two errors.

This joke derives its humor from self-reference. For a better example of self-reference, have a look at the Self-Referential Aptitude Test by Jim Propp. This is an exceptional puzzle and a lot of fun, but allow yourself between 20 minutes and 2 hours to complete it.

I completed the SRAT in less than 20 minutes.
Both of these statements are false.

For my money, Groucho Marx delivered the best self-referential joke of all time:

I would never join any club that would have me as a member.

Neither would I, Groucho. Neither would I.

July 14, 2010 at 1:47 am 4 comments

About MJ4MF

The Math Jokes 4 Mathy Folks blog is an online extension to the book Math Jokes 4 Mathy Folks. The blog contains jokes submitted by readers, new jokes discovered by the author, details about speaking appearances and workshops, and other random bits of information that might be interesting to the strange folks who like math jokes.

MJ4MF (offline version)

Math Jokes 4 Mathy Folks is available from Amazon, Borders, Barnes & Noble, NCTM, Robert D. Reed Publishers, and other purveyors of exceptional literature.

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