My guest today, Stephen Stroghets, is a professor of mathematics at Cornell University and has done some of the most influential math research of the last few decades.

But Stephen Stroghets isn't what you'd expect from the math magician.

It was insane to have a paper that had, as its examples, the power grid of the Western United States,

the neural network of the one organism whose neural network had been completely mapped at that point,

and the graph of Hollywood actors who have been in movies with each other,

popularly known at the time as the six degrees of Kevin Bacon.

Welcome to People I Mostly Admire with Steve Levitt.

Stephen Stroghets studies real-world problems and he has a gift for making math fun and accessible

even to people who have math phobia. Through his best-selling books, his New York Times column,

and now his podcast, The Joy of Why, he's probably done more to make people appreciate the power

and beauty of mathematics than anyone else in modern times.

I want to start by saying that I thought of you this morning. I've been reading Infinite Powers,

which is your book about calculus, and I was thinking about it absolutely as I got in the car.

I've lived in Chicago for a long time, which is perfectly flat, but right now I'm living in Germany,

and I live on the top of a big hill. Coming out of my garage, my driveway goes downhill.

Being the absent-mind professor that I am, I didn't bother to survey the situation and

there was ice covering the driveway, and so as I began to drive down it,

I realized the brakes had no effect at all. There's zero friction. I wasn't moving very quickly,

but it is a long downhill driveway. Actually, a time to think about you and Galileo,

and I knew enough about how acceleration works. That I knew by the time I got to the bottom,

I was going to be going pretty fast. And indeed, I slammed into the embankment

at the bottom of the driveway fast enough that the entire front of the car just shattered into pieces.

...