My guest today, Robert Zipolsky, may know more about baboons in the wild than anyone else on the planet.

On top of that, he's a leading neuroscientist who's made breakthrough discoveries on stress and gene therapy.

He also dabbles in philosophy, arguing that free will is nothing but an illusion.

On top of all that, he's found the time to write a half dozen bestselling and critically acclaimed books.

Welcome to people I mostly admire with Steve Levitt.

This would be my first time talking to Robert Sapolsky, and I'm really curious to see what it's like.

I've read every one of his books, so in an odd way, he feels like a friend, even though I've never

met him or even heard his voice. In pictures, he's got a big white beard and long curly hair that

would make Santa Claus jealous, which has led me to make all sorts of assumptions about how he'll speak and even about his personality.

We shall see if looks are deceiving.

Now, the two topics I want to cover for sure today are stressing humans, and that's a topic on which he's an expert and I am absolutely not an expert,

and violence, where we both might have legitimate claims to be experts,

although we've approached the issue from opposite perspectives.

I suspect those two parts of the conversation will be very different.

But before we hit those topics, I want to hear about the baboons.

Robert, so good to meet you.

Same, a big fan.

So you grew up in an Orthodox Jewish family in New York City,

and then you graduated summa cum laude from Harvard.

And I'm not sure I can think of a worse preparation than that for spending years in the wilds of Kenya living with baboons.

Well, I think that's a pretty good summary of things.

At the time I first went out to Africa, which was about a week after graduating college. I had been as far

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