Magic Numbers

Arthur Benjamin turns math into magic. He solves equations faster than some calculators do. Tell him your birth date and year, and he’ll tell you what day of the week it was. He performs his stage act, That Math Show, around the world. And he teaches at Harvey Mudd College, in California. I spoke with Benjamin about his career. He taught me math magic on the spot. Read part of our conversation here.

Are you the only mathemagician?

I’m sure there are others. But I’ve been using the term for a long time. I’ve always had a love for mathematics and magic. Mathemagician is the appropriate description of what I do. I present mathematics in a magical way, to entertain and to inspire people to enjoy mathematics more.

How do you bring math and magic together?

In my performances, I race calculators. I’m not cheating. I’m doing the calculation. But I’m doing it so fast, it seems like magic. I hope that when I present it, people are amazed.

How do you come up with a math magic trick?

I’ve been doing a lot of the same tricks for a long time, but I keep my eyes open. I read books by other magicians. I read articles by other mathematicians. When something catches my eye, I add it to my performances or my lectures. A lot of times, my performances will involve questions from the audience.

Have they ever stumped you?

I don’t get them right 100% of the time. If I’m wrong, I’ll talk through the process slowly and usually find the mistake. The only way you can grow in any subject or any skill is to be willing to make mistakes. If you’re afraid of mistakes, you won’t grow.

This interview has been edited for length and clarity.