Robert Sapolsky: How Much Agency Do We Have Over Our Behavior?

Aug 25, 2017
Originally published on August 28, 2017 10:17 am

Part 1 of the TED Radio Hour episode Hardwired.

About Robert Sapolsky's TED Talk

Neuroscientist Robert Sapolsky says nearly all aspects of human behavior are explained by biology: from developments millions of years in the past to microscopic reactions happening in the present.

About Robert Sapolsky

Robert Sapolsky is a primatologist and a professor of neuroscience at Stanford University. His current research examines how stress alters personality patterns and social behavior.

Sapolsky's latest book, Behave: The Biology of Humans At Our Best And Worst, tries to answer the question, why do we do the things we do?

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It's the TED Radio Hour from NPR. I'm Guy Raz. So most of us think we know ourselves pretty well, right?

ROBERT SAPOLSKY: I'm sort of a hippie pacifist in terms of general persona.

RAZ: That we're good people...

SAPOLSKY: You know, I'm an egg-heady scientist with a large beard and like Birkenstocks.

RAZ: ...Who make good choices.

SAPOLSKY: Give an error of equilibrium as much as possible.

RAZ: But do we really know who we are and why we act in certain ways? And do we have any control over that anyway?


RAZ: This is Robert Sapolsky. He's a professor of neuroscience at Stanford University.

SAPOLSKY: We have very different potentials and sort of tendencies for behavior lurking in us. And I think some of the most sort of surprising, shocking, appalling, wonderful cases of sort of human behavior is when one side of it suddenly comes out from a person who never ever expected that. At one extreme, you have the person who suddenly runs into the burning building...


UNIDENTIFIED REPORTER #1: People running into the fire to save a trapped man.

UNIDENTIFIED WOMAN #1: (Unintelligible) A dad out there.


SAPOLSKY: ...While everyone else is sort of being headless chickens not knowing what to do.


UNIDENTIFIED WOMAN #1: No, there's a man inside.

SAPOLSKY: Wow, I never knew I had that in me.


UNIDENTIFIED WOMAN #1: Oh, thank god.

UNIDENTIFIED WOMAN #2: Everybody's out.

UNIDENTIFIED WOMAN #1: Here he is. Is this him right here?

SAPOLSKY: At the other extreme, you have people ranging from, like, the Abu Ghraib scandal...


UNIDENTIFIED REPORTER #2: Disgusted by pictures of Iraqi prisoners being abused by American soldiers.

SAPOLSKY: ...To, like, the famed Stanford Prison Experiment...


UNIDENTIFIED GROUP: Prisoner 819 did a bad thing. Prisoner 819 did a bad thing.

SAPOLSKY: ...Where people turn out to do things never in their darkest moments would they've imagined they were capable of.


UNIDENTIFIED MAN #2: And I was dismayed that I could act in a manner so absolutely unaccustomed to anything I would even really dream of doing.

SAPOLSKY: We're capable of a lot of stuff. What is sort of human nature when it comes to these good and bad behaviors? And the answer is going to be it depends - when, where, what you had for breakfast, what you had when you were a fetus in somebody's womb back when, what your culture has been, little bit of what your genes are, how your brain is wired up. It depends. It depends enormously on context.


RAZ: So on the show today, we're going to explore a lot of that context - ideas about whether we're hardwired, about what makes us who we are, and why we behave the way we do. How much of that is biological? How much of it is learned? And how much of it, if any, can we change? And as Robert Sapolsky points out, human nature and its whole spectrum of behaviors is complicated, even for the people who study it because despite his serene presence...

SAPOLSKY: I'm sort of calming enough that my students regularly nap during my lectures so that must be a good index of that.

RAZ: ...Robert actually has a pretty violent recurring fantasy. Here's how he described it on the TED stage.


SAPOLSKY: Fantasy always run something like this. I've overpowered his elite guard, burst into his secret bunker with my machine gun ready. He lunges for his Luger. I knock it out of his hand. He lunges for his cyanide pill. I knock that out of his hand. He snarls, comes at me with other-worldly strength. We grapple. We fight. I manage to pin him down and put on handcuffs. Adolph Hitler, I say, I arrest you for crimes against humanity. Here's where the Medal of Honor version of the fantasy ends and the imagery darkens. What would I do if I had Hitler? And it's not hard to imagine once I allow myself. Sever his spine at the neck. Take out his eyes with a blunt instrument. Puncture his ear drums. Cut out his tongue. Leave him alive on a respirator, tube fed, not able to speak or move or see or hear, just to feel. And then inject him with something cancerous that's going to fester and postulate until every cell in his body is screaming in agony, until every second feels like an eternity in hell. That's what I would do to Hitler.

RAZ: Wow. Robert, you got like this violent streak. You're supposed to be this hippy pacifist. And then you have this very vivid fantasy.

SAPOLSKY: Well, yeah. I've had that one since I was little. A remarkable number of people have now told me that they've had ones along similar lines. And I'm this person who, like, is far from being violent as possible, yet I harbored these thoughts. Yet I'm opposed to the death penalty. Yet there's some people I would certainly like to see removed from the planet. And I like violent movies, but I'm for strict gun control. You know, we're all a confusing mixture of a whole array of impulses. And the biology underlying the fact that some of those impulses come to the forefront in some circumstances and the others, you know, in other contexts is this huge challenge biologically. Our nature is to be context-dependent on our behavior.


SAPOLSKY: So how do you make sense of the biology of our best behaviors, our worst ones and all of those ambiguously in between? The challenge is to understand the biology of the context of our behaviors. And that's real tough. One thing that's clear, though, is you're not going to get anywhere if you think there's going to be the brain region or the hormone or the gene or the childhood experience or the evolutionary mechanism that explains everything. Instead, every bit of behavior has multiple levels of causality. But to understand that, we have to step back a little bit. What was going on in the environment seconds to minutes before, hours to days before, back years, back, for example, to your adolescence...

UNIDENTIFIED CHILDREN: (Singing) Happy birthday to you.

SAPOLSKY: ...Even further back to childhood, back to when you were just a fetus, back to when all you were a collection of genes, back centuries - what were your ancestors up to? - back millions of years because if we're talking about genes, implicitly, we're now talking about the evolution of genes. Basically, what we're seeing here is if you want to understand a behavior, whether it's an appalling one, a wondrous one or confusedly in between - if you want to understand that, you've got to take into account what happened a second before to million years before, everything in between.

RAZ: OK. So if we're just the sum of all these parts, what do we actually control?

SAPOLSKY: Well, just to really take us into (laughter) potentially not-touch-with-a-10-foot-pole territory, my personal bias is we've got no agency at all. I don't think there's a shred of free will out there. From spending my decades thinking about behavior and the biological influences on it, I'm convinced by now free will is what we call the biology that hasn't been discovered yet. It's just another way of stating that we're biological organisms determined by the physical laws of the universe.

RAZ: So everything that you're saying here now and everything that I'm saying to you now and the things I'm going to do for the rest of the day and that you're going to do for the rest - and the interactions you're going to have and I'm going to have, we have very little say in that?

SAPOLSKY: Actually, remarkably little sort of conscious access to it. An awful lot of the time, say, if we choose a behavior, it turns out there was some subterranean emotional tumult that led to that. For example, when you put people in positions of making moral judgments about behavior, you see, for example, more emotional parts of the brain activate sooner than the cortical parts. I mean, one study that just floors me in that regard was carried out in Israel - all of the judges in Israel hearing parole board hearings over the course of a year, something like 5,000 cases, and then looking at who got granted parole, who got sent back to jail, looking at all sorts of variables - and the strongest predictor of judges' decisions was how many hours it had been since they'd eaten a meal...

RAZ: Wow.

SAPOLSKY: ...Which is boggling, except it's not because there's a biology that explains it. And they're not going to say because I'm hypoglycemic right now, and it's hard to feel empathic towards - they're going to quote some philosopher they had to read in law school or whatever they're going to assume and fill in the void with sort of pretenses of pure agency. You know, with every passing year as we learn more and more about every one of these domains and what has to do with behavior, the things where we used to say, ah, that's volitional, ah, that's him and what he chooses or chooses not to do - more and more of that keeps falling by the roadside as we say, ah-ha (ph), no, actually. It turns out that's a psychiatric disorder with these genetic components. Ah, for example, this is not a child who is lazy and unmotivated. There's little micro abnormalities in that kid's cortex producing learning deficits. And, you know, when you look at the space that free will has been getting crammed into, more and more so, with each passing year of insights into the biology of behavior, got to say, it's going to get really, really crammed in or nonexistent at some point.

RAZ: Yeah. Yeah.

SAPOLSKY: At the same time, I realize I have absolutely no idea how somebody is supposed to really believe that stuff. Intellectually, I believe there's no free will. But I still have absolutely no idea how to get around complimenting somebody on, like, their new hairdo...

RAZ: Of course, of course you would. Yeah.

SAPOLSKY: ...Or being pleased if somebody says something complimentary to me.

RAZ: Yeah. Or like a charitable thing that they did. You would say, hey, that was so great.


RAZ: This is so complex. And what's amazing about it is that, I mean, you acknowledge that there are things about this thing even you don't understand.

SAPOLSKY: Oh, yeah. And worse is there's things about it that I understand, which, nonetheless, I have no idea how to incorporate into behavior.

RAZ: So, I mean, can we move past our biology?

SAPOLSKY: Nah. That's all there is. For better or worse and everything in between, there's no little homunculus sitting on our brains there that's inside the brain but not made of brain yuck (ph) and instead is made of, like, gumption and backbone and Calvinist self-discipline. It's biology all the way down. There's not a separate thing. We are the sum of all that.


RAZ: Robert Sapolsky. He's a professor of neuroscience at Stanford University. You can see his full talk at On the show today, hardwired and in a moment, a different take on whether we can change our biology. I'm Guy Raz. And you're listening to the TED Radio Hour from NPR.

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