For something on the lighter side, here’s a fun video that I’ve seen linked to from a number of places. It’s a video of Arthur Benjamin, a math professor at Harvey Mudd College, performing a fifteen-minute “mathemagics” show. He multiplies numbers in his head, figures out the day of the week on which people were born, and some other things, all while keeping up an entertaining banter. It’s quite fun, watch it if you’ve got a spare fifteen minutes!

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### Meta

At first I felt like he was just a terrible show-off, but then I chided myself, thinking of all the times other people have expressed that opinion of someone and I didn’t approve. It’s partly a matter of the cultural iniquity that makes it more okay to brag about athletic achievements than brainy ones. Also, a college associate called my friend a big jerk (or a less pleasant synonym) simply for not telling his magic secrets when asked. When I told her that magic books emphasize this silence as an important rule, she expanded her insult to all orthodox magicians.

This case may be a little different, tho. I’m not sure of all the techniques Mr. Benjamin uses, but he doesn’t leave me feeling like it was magic, or even a trick per se. Maybe I’m dulled to his talent from having heard about others with it. Not just the Rain Man, but the famous Twins who could tell you the day of the week for any date or any Easter in an 8,000-year span (but bombed at simple arithmetic problems).