Principle of Explosion
by Jeff
Image text: You want me to pick up waffle cones? Oh, right, for the wine. One sec, let me just derive your son's credit card number and I'll be on my way.
The principle of explosion means that if you assume that something is both true and untrue at the same time, then you can prove any conclusion. Usually, someone would prove that something is true or false, but in the comic, the principle is used to derive a phone number and a credit card number. The joke in the comic is taking the mathematical logic to the next level to make a joke about the first character's mom.
The equation in the third frame is the typical notation for a principle of explosion equation. It means "P and Not P". P represents some statement such as "the sky is blue". So, the equation is: "The sky is blue and the sky is NOT blue." From that premise, you can prove anything. In the comic, you can even prove a phone number or credit card number.
February 19th, 2010
…k at least I feel like I learn some stuff from reading XKCD. Also did you know theres a script that prevents you from posting comments that are “Too short”
February 20th, 2010
The math, I get. But. . . . box wine from a waffle cone? Now, that is just demented.
February 20th, 2010
I was curious about Mrs. Lenhart, knowing xkcd, that couldn’t be at random. So I googled around a bit to find out any lenhart related to computer science, it turns out Lenhart K. Schubert (http://www.cs.rochester.edu/~schubert/) seems related to Epsodic Logic (EPILOG)… Though it’s not the family name, so maybe if I googled “Lenhart potatoes” instead of “Lenhart logic” I would’ve found a farmer named Lenhart.
Awaiting confirmation then
February 20th, 2010
Mrs. Lenhart is a minor but recurring character in xkcd. She appears or is mentioned in http://xkcd.com/135/, http://xkcd.com/416/ http://xkcd.com/499/ as an elementary school teacher.
May 19th, 2010
And there’s goes that research. lol