As a math-lover, would-be teacher, and Dad to two teen-agers, the idea of using simple cartoons to teach math and logic really appeals to me. This cartoon is an example of the comedy stylings of one Christopher J. Burke, a math teacher and cartoonist.
Please see the original here:
(x, why?) #596: Coffee Logic - Wed, May 18, 2011. Also visit Chris' blog where you may read discussions of this cartoon and post comments about it. You may also enjoy flipping through the hundreds of cartoons available for your perusal, as did I.
More on that in a future post.
Like many new fans, I was introduced to Chris' work by Mike at Spiked Math. I re-posted Mike's cartoon last week:
http://philosfx.blogspot.com/2011/10/friday-humor-three-logicians-walk-into.html. Mike referred viewers to Chris, and Chris reported a huge spike in readership as a result.
Mike used a beer bar scenario instead of a coffee shop scenario, but his comic has a similar punchline, based on the same logic. A question is posed to the group about the group in such a way that the assumed group response is Yes. The first individual to respond cannot know what the rest will say, so logically he cannot say Yes for the group. He can say No if he himself would say No because that No would also be true for the group. If he wants to say Yes for himself, he must say I don't know. If he says I don't know, the next person has the same dilemma. The uncertainty about the group's position decreases with each successive responder. After a string of I don't knows, the last responder can answer either Yes or No with certainty.
What makes the joke funny to me is that most people ignore logic in daily life. Real life is full of uncertainty. Mathematicians, logicians, and computer programmers are good at reducing uncertainty to a series of binary decisions--but most of us just simply do not think that way. Next time you're out with friends at a bar or coffee shop, watch what really happens in this scenario! Now that you are in on the logic, you may just chuckle quietly to yourself and enjoy the inside joke.