Steven Pinker on Morality as a 'Sixth Sense' Is moral sense hardwired in the human brain? Psychologist Steven Pinker examines morality and evolutionary roots and discusses his article, "The Moral Instinct," published recently in The New York Times Magazine.
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Steven Pinker on Morality as a 'Sixth Sense'

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This is TALK OF THE NATION. I'm Neal Conan in Washington.

In the "The Moral Instinct," an article published in The New York Times Magazine, Harvard psychologist Steven Pinker writes about a new sixth sense, what he called the moral sense - our ability to consider some questions as moral issues while others are addressed with the practicality of cost-benefit analysis. Take meat, for example. One person could be a vegetarian for ethical reasons to avoid causing pain to animals while someone else might be a vegetarian to lower cholesterol. For that person, it's a practical question of health, not morality.

Today, psychologists, neurologists and biologists are trying to figure out how we make moral judgments and why, and why we newly elevate some issues to the plane of morality - smoking for instance - and learn to think of previously moral questions, like divorce, on a more pragmatic basis. And if this is a science, if the moral sense is hard-wired into our brains, does that reduce what many would regard as our best impulses to mere biology?

If you'd like to talk with Steven Pinker about morality and how we categorize some issues as right and wrong but not others, our number here in Washington is 800-989-8255. The e-mail address is, and you can weigh in on our blog at

Later in the program, NPR's Howard Berkes joins us to explain how the Mormons will choose a new leader, but first, the moral instinct.

Steven Pinker, the Johnstone Family Professor of Psychology at Harvard University, joins us now from a studio on the Harvard campus in Cambridge, Massachusetts. And Steven Pinker, nice to have you with the show again.

Professor STEVEN PINKER (Psychology, Harvard University): Thank you.

CONAN: And why do you think there is a science of morality?

Prof. PINKER: Morality is clearly a judgment that comes out of our emotions and our reason. It's a psychological phenomenon which may have objective counterparts but it certainly has psychological counterparts. The example that you raised of the two kinds of vegetarians, a phenomenon first discovered by Paul Rozin, is a wonderful example because the behavior is the same, avoiding meat, but the whole set of thoughts and emotions that go along with it very much depends on whether you think it's a moral decision or a practical one.

To take one example, if a drop of meat broth falls into your vegetable soup, will you avoid even touching the soup? Well, if you're a health vegetarian, obviously, one drop is not going to raise your cholesterol levels. But if you avoid meat for moral purposes, then a mere drop is a contaminant and it compromises your identity even to taste it, and so you avoid it. Or you think, for example, that people who avoid meat are less aggressive and less animalistic, if you're a moral vegetarian. If you're a health vegetarian, you wouldn't make that kind of attribution. So it suggests that there's something in our psychology that goes along with being in a moral mindset, and so moral judgments are a topic in psychology and ultimately, biology just as color vision or smell is.

CONAN: One of the new tools that scientists have to use to take a look at our brain is the functional MRI that can actually see the brain in operation while it's making decisions about various things, and what is that show about moral decisions as opposed to other kinds of decisions?

Prof. PINKER: A nice example comes from the work of my colleague, Josh Greene, who looked at one of the favorite sandboxes for the new moral psychology, sometimes called the trolley problem. Namely, if you pose the following moral dilemma to people, a trolley is hurtling out of control, there are five workers on the track who are going to be killed as the trolley plows into them; they haven't seen the oncoming danger. You're standing at a switch; you can divert the trolley on to a sidetrack.

Unfortunately, in the sidetrack there's a single man working who will be killed because he also hasn't noticed the danger - should you pull the switch? Saving five lives at the cost of one and just about everyone says yes all over the world. Now, if you change the physical terms of the problem, you say well, this time, you're standing on a bridge overlooking the tracks. You see the trolley hurtling out of control. The only way to stop it is to throw a heavy object in front of the trolley, and the only heavy object available is a fat man standing next to you - should you throw the fat man over the tracks? This time, people say it's not permissible to sacrifice one life in order to save five. Then you might think the mathematics are the same one - kill one, save five - why should it make so much of a difference how the physics work? Greene proposed the difference is that we have an innate revulsion, perhaps even rooted in evolution, to directly manhandling an innocent person.

And so if you simply switch the track and then a chain of events occurs that will eventuate in a person getting killed, psychologically, that's different from doing it with your bare hands. And indeed, if you put people in a brain scan or while they're thinking through these dilemmas, that in the case of the fat man on the bridge problem, then an area in the frontal cortex that's associated with empathizing with other people lights up. And in the simpler problem where you simply have to divert the train onto a side track, that area does not light up. Also, in the fat man version of the problem, another part of the brain that's involved in conflict in weighing two things to decide which you should go with, lights up confirming that people are grappling in that case with a conflict between the calculus of one life versus five and the gut feeling that you can't hurl a struggling man over a bridge.

CONAN: And why does evolution enter into this? Why would evolution play a factor?

Prof. PINKER: The first suspicion is that some kind of moral intuitions are universal, not the same intuitions, of course, because in some cultures, it's considered moral to, say, kill your sister if she's had sex with someone you don't approve of, and in other cultures, it isn't. But the idea that there is a moral coloring to acts, that there are some acts that deserve to be punished, that ought to be discouraged, seems to be found in all cultures together with proscriptions against rape and murder and theft. A sense of empathy not always directed at every other human being, sometimes only to members of one's own clan. So the universality of morality is a hint that it might have an evolutionary basis, and models of how social cooperation can evolve point a finger at certain emotions like guilt and sympathy and gratitude and righteous anger as mechanisms to get people to cooperate without being exploited. And so the combination of the universality and the availability of a plausible mechanism by which moral sentiments could evolve suggest that it might be part of our evolved nature as is color vision or fear.

CONAN: We're talking with Steven Pinker of the family, Perth Johnstone family professor of psychology at Harvard about his piece "The Moral Instinct" that was published in The New York Times Magazine. Again, if you'd like to join us, 800-989-8255, e-mail is

John's(ph) on the line from San Francisco.

JOHN (Caller): Hello?

CONAN: Hi, John. You're on the air. Go ahead, please.

JOHN: Yes. I'd like to thank Steve Pinker for all the work he's done. And my basic comment is that I think morality is closely connected to the survival of the group that one belongs to. As a young man, I thought often about morality of war and how one side could be fighting against the other side, and each side think that they're doing the moral, you know, doing the moral purpose. And I think as society changes, I think that the group the one belongs to changes so that the act is not - of course, the act that one does is very important, but the group that one belongs to is actually changing.

Prof. PINKER: Yeah. Yes, we certainly - first of all, there certainly is a large amount of self-deception in the nobility of one's own group's cause. Both sides in a typical war believe that they are morally in the right and that the other side is a bunch of conniving, immoral psychopaths. And obviously, they can't both always be right. I suspect that we do have group feelings, although I think the easiest target for them is the clan or family, which is why nations and armies so often try to instill in their members a false sense of family belonging, kinship metaphors like the fatherland and the mother country and brothers in arms, communal meals - other ways of basically brainwashing individuals into thinking that they are in effect fighting for their clan or family, whereas, in fact, they're fighting for a much larger and more abstract entity called the nation state.

CONAN: Thanks for the call, John.

JOHN: Thank you.

CONAN: And Steve, the other thing you raise is that there are different ways of thinking about this. If you regard something as a pragmatic issue - again, going back to that example we used of the two vegetarians - the health vegetarian and the anti-meat vegetarian, if you think about it on a pragmatic level, where you're going to make decisions certain ways. But if you think about it as a moral issue, well, then, it is wrong - capital W - to eat meat and you should try to persuade other people from eating meat. There are certain actions that making a moral judgment dictates.

Prof. PINKER: Exactly. So even though I'm in favor of abortion rights, I've always objected to the bumper sticker that says if you're against an abortion, don't have one because that is equivalent to saying if you're against murder, don't kill someone. It misses the point that if abortion is a moral issue to anyone, then just agreeing not to do it yourself is not an option. It's like saying if you're against rape, don't rape someone. The very fact that it's considered moral by some people means that necessarily, it has to apply to everyone.

Now, one could argue that, of course, in the case of abortion, the right of the woman trumps any right of the embryo or the fetus. And I think there is a legitimate argument to be made along those lines. But to trivialize it by saying it's just a matter of personal choice, I think, is to fail to engage the other side in a reasonable debate.

CONAN: And then how does something - and you make the example of smoking - go from something which was, hey, you can smoke, you don't smoke, no big deal, to, all of a sudden, becoming a moral issue?

Prof. PINKER: I think a lot of social and political and cultural change consists of moving behavior from the moral side of the page to the non-moral side or vice versa.

For example, homosexuality is something that used to be considered to be immoral, as was almost every form of sex that didn't lead to children -contraception, pre-marital sex and so on. Now, we consider it just a matter of choice. Or divorce, atheism, homelessness, even, which used to have a moral taint when we would call someone a bum, which both implies that they have no home and that somehow they're responsible for it. Those are examples of behaviors that have become immoralized.

On the other hand, things like, say, executive pay, which, a few years ago, would have been not a moral matter at all. If some corporation is stupid enough to pay exorbitant fees to some CEO who runs the company into the ground, that's none of my concern. But now, with concerns about inequality and of corporate mismanagement that leads to unemployment, it's everyone's business and it's considered a moral issue how much a CEO gets paid.

CONAN: We're talking with author Steven Pinker about morality this hour. And what makes your moral compass spin? Nature or nurture? We're taking your calls. 800-989-8255. E-mail us, And stay with us.

I'm Neal Conan. It's the TALK OF THE NATION from NPR News.

(Soundbite of music)

CONAN: This is TALK OF THE NATION. I'm Neal Conan in Washington.

Morality is something that feels fixed. You might feel right and wrong in your very bones. But as we were just discussing, some issues are mutable - divorce, illegitimacy, even smoking - once regarded as moral issues are not so regarded anymore. Smoking, of course, gone from the other category, regarded as a pragmatic issue, now regarded by many as a moral issue.

We're talking about the moral instinct and where it comes from with Steve Pinker this hour. He's the Johnstone Family Professor of Psychology at Harvard. You can find a link to his article about the moral instinct on our Web site at

And of course, we want your input as well. Where do you think our notions of right and wrong come from? You're invited to join the conversation, 800-989-8255. E-mail us, And you can check out our blog at

Let's go to Brian(ph). Brian is with us from Fort Wayne, Indiana.

BRIAN (Caller): Yeah. Hi. One question that I had was, it seems to me that morality tends over history to change a lot with the economic and political status of whatever is happening at the time. And the other thing I tend to have noticed just looking at history is that those non-pragmatic morality issues seem to be focused when a certain group has a problem in another area. And the perfect example is the homosexuality and divorce scenario you just talked about. Divorce, growing incredibly with the, you know, the Christian groups that used to not be, you know, nearly as prevalent as is now. All of a sudden, we've changed that. And we need to bash somebody else for their sin, which we think is more important. And it seems to take the concentration off our problems, which is, you know, this divorce rate which, historically, was a very conservative, and you just didn't do it, and it was a very small percentage. I'll take my thing off the air.

CONAN: Okay, Brian. Thanks very much for the call.

Prof. PINKER: Yes, there is a certain tendency, I think, to moralize the other guy's behavior as supposed to your own. So the - a gas-guzzling Hummer, for example, is considered a moral outrage among people who drive old, beat-up Volvos which might even - and get the same amount of pollutants. Or a Big Mac as opposed to creme brulee or tiramisu and vice versa often among more right wing groups. The kinds of practices that are characterized urban elites tend to have more of a moral taint than ones that go on in their own communities.

So one of the things that go along with moralization is a certain amount of self-deception, namely, what I do is moral. What the other guy does deserves to be punished.

CONAN: And you write that, in fact, this is - there are about five principles of morality. But prioritizing them from one culture to another can vary even within our own culture, left and right in the culture war, so-called, would prioritize those values differently.

Prof. PINKER: That's right. If - I think, basically, any emotional reaction that we have to another person can become moralized. So we - if someone is dirty or contaminated, we obviously shun them. But we also tend to slide into thinking that there must be something wrong with them, any kind of behavior that we think of as repugnant to ourselves, we tend to moralize. And I think that's why, say, homosexuality, which is a bit of a puzzle why anyone should have ever thought it was immoral, given that it doesn't hurt anyone. You might even have thought that evolution would have favored not encouraging homosexuality, among others, because, you know, more women for me if everyone else is gay.

But people do more - did, at least. In some cases, still do moralize homosexuality, I think, because if it's repugnant to themselves, it tends to blend in the brain with moral judgments. So there's a purity versus contamination mindset to moralization, which is also why we revere ascetic, spiritual leaders who dress in white and seem to be emotionally detached from the world as opposed to carnal, sensuous hotheads.

There's also group loyalty and conformity to norms, which tends to get moralized. There is an avoidance of harming someone for no reason. There is fairness - the idea that you shouldn't take a benefit without paying for it. And that you shouldn't harm someone without getting punished. And then there is deference to authority, the idea that leaders should be revered and not challenged. Those are 5 different threads to morality. And the weighting that they get differs from culture to culture and even between the left and right in our own culture, where Jonathan Haidt first formulated this five-sphere theory of morality.

He's noted that liberals tend to put almost all of the moral emphasis on avoiding harm and unfairness. Conservatives tend to give a somewhat lower weight to those two and a higher weight to group loyalty, deference to authority and purity.

CONAN: Let's get another caller on the line. This is Chuck(ph). Chuck calling us from San Francisco.

CHUCK (Caller): Thank you very much. I tend to - well, William James and a variety of religious experience talked about mystical religious experience as having a noetic quality, which is to say it's a - it gave you a sense of - there was a way of knowing. And I tend to think that aesthetic and religious experience, emotional, subjective experience, does give us access to a plane of truth that is quite apart from the material, scientific one and is no less true. But your theory, if I understand it - I read your article - says that emotions play a very key point in the process by which we come to moral decisions. And it seems to me that if - that the theory itself - which is to say that moral reasoning is the product of biology and evolution - affects the way we would approach, the way we understand the process of moral reasoning, which is to say if people don't think that the reason they do things is because it is transcendently, religiously, absolutely true but because it's the product of their biology and evolutionary process, doesn't this in a way interfere with the very foundation by which we come to a moral conclusion, which is an emotional one, by changing our view of the whole process of moral reasoning?

Prof. PINKER: Well, I do deal with that in the article. Indeed, I think there's a third alternative to the idea that morality is dictated by religious texts and the idea that morality is just a product of the wiring of our brain. There is a certain logic to morality. One of them is the logic of non-zero sum games. The idea that two parties can both come out ahead by behaving in certain ways and not others, so if I refrain from stealing your property and you refrain from stealing mine, we're both better off than if we're constantly raiding each other and feuding like the Hatfields and the McCoys. Or if I give you some of my surplus when I've got more than I can eat and you're starving, and you decide to do the same thing when fortunes reverse, we're both better off.

And part of the morality, which is valuing another person's interest like your own, therefore has an objective basis in any social and self-interested group of intelligent agents.

The other is just the logic if intellectual discourse in the first place. If I'm discussing with you how you ought to behave, if I say you should get off my foot, it's hurting me. And there are good reasons for you to get off my foot. If I say you shouldn't run me down with your car as a shortcut to get to the grocery store but drive around me. Anything that I implore you to do has to apply to me as well. I can't - I have to get off your foot. I have to avoid running you down with my car if I want you to take me seriously. Otherwise, it's just an irrational thing for me to try to persuade you to believe.

So the interchangeability of perspectives, the basis of the Golden Rule is a fact of logic that doesn't come from peculiarities of how evolution wired our brain. It doesn't come from the Bible or any other holy book. But it's just, in some sense, in the nature of things, in the nature of rationality. And I argue that that is why there is such a thing as morality separate from our evolved moral sense but that religion itself has nothing to do with it.

I don't think it's just emotion either. These are both rational arguments that consulting moral emotions is, in general, not a good way to find the most defensible course of actions because people have done horrendous things in the throes of various emotions.

The idea that black and white people could drink from the same water fountain, the idea that Jews and Germans could have sex, the idea of blood transfusions, the idea of consenting homosexual behavior. All of these were considered emotionally, deeply repugnant in their own time or place. Now, we can argue that there's nothing wrong with any of them despite whatever negative emotional reaction someone may have had at the time.

CHUCK: Can I just say that - but it does seem that with gain theory and with the Golden Rule, even, as being kind of explained from a utilitarian perspective, it does rather undermine the notion of a kind of an ultimate abstract transcendence sort of moral principle being the basis or the foundation for our behavior. And as such, for example, you know, it may apply conveniently if we're talking about people standing on each other's foot. But what about the sort of altruism where, for example, the soldier that throws himself on the grenade? That is not going to benefit him. I mean, and you end up getting, you know, again, you can come up with a kind of, a sort, a game theory explanation but they always end up, to me at least, sounding kind of watered down and not nearly as morally powerful and persuasive as the traditional foundations of morality.

Prof. PINKER: I guess I would have to disagree that ultimately basing it in a kind of reason that I can't wiggle out of and you can't wiggle out off is more persuasive than any kind of religious source, which not only depends on what religion you were born into but ultimately needs its own justification. Just because it's written down in some text, why should we treat it as a moral obligation, and how did it get there in the first place?

CHUCK: I thinkā€¦

Prof. PINKER: If you believe that morality was handed down by God, what basis did he have for deeming certain acts moral and others immoral and if he had gone the other way, would we have have to obey him? If he said go ahead and torture a child, would we be compelled to obey and if not, what principles would we be appealing to in overriding an immoral divine edict? For that reason, I don't think that traditional religion is a viable source for morality and ultimately it does have to be rooted in some rational exploration of interchangeability of perspectives.

CONAN: Chuck, thanks very much.

CHUCK: It's super religious and it's not that - that perhaps that's a discussion for another day. Thank you very much.

CONAN: Thanks for the call.

Let's see if we can go now to Scott(ph), and Scott is on the line with us from Tulsa, Arizona - Oklahoma, excuse me.

SCOTT (Caller): Yes. Well, I just am kind of commenting on the conversation you were having just a little bit ago. I think that a lot of, you know, what's true in the Bible about every man does what is right as it owns - in his own eyes kind of holds it absolutely, we end up going into a moral drift. And as society tends to put constraints on these but if everybody's out sacrificing people as an accepted societal standard even though we know now that it's wrong then wouldn't that also - didn't that - we have moral absolutes?

Prof. PINKER: Well, I think we do have moral principles, I'm not sure they'd be absolutes because you can always think of a reason, extenuating a set of circumstances, in which any given principle might had to be trumped by another on. So it's wrong to kill someone but, of course if it's in self-defense or if it's in defense of somebody - other innocent person or in case, certain cases of justifiable war then of course it is permissible to kill someone else.

CONAN: Well, presumably, the Aztec priest who tore the beating heart out of a sacrificial victim thought that they had, they were perfectly moral in doing so.

SCOTT: Exactly.

Prof. PINKER: Right. And they were wrong. They were not acting morally and we - although by their own lights, they were and that is, I would say, that it speaks a good illustration of the difference between moral psychology or moralization on the one hand and morality itself on the other. I think we do need principles, I'm just disputing that they ought to come from religion because you still have to choose which religion should give you your principles, which principles you choose and which ones you ignore.

For example, the Bible says that anyone who disobeys his parents or blasphemes God should be stoned to death. We ignore that moral principle from the Bible and rightly concentrate on thou shall not kill. That suggests that we must be appealing to some standard as to which principles from the Bible we choose and which ones we reject, hence, that I think is actually proof that our standards of morality ultimately don't come from religion because they tell us which of those religious precepts we take seriously and which ones we try to ignore.

CONAN: Scott, thank you.

SCOTT: Well, I do agree to a certain extent with that but isn't it also in the New Testament that Jesus said he who is without sin let him cast the first stone in the same precept.

CONAN: Thanks, again, for that Scott.

We're talking with Steve Pinker and you're listening to TALK OF THE NATION from NPR News.

And, Steve, I heard you try to come in on that last thought.

Prof. PINKER: Oh, yes, well, let me say, a wise directive against taking our own sanctimony too seriously, although, Jesus, of course, did accept everything in the Old Testament, he didn't abjure everything and - but I do agree that's a wise counsel.

CONAN: Let's see if we can get another caller in. And this is David(ph), David with us from Manhattan in Kansas.

DAVID (Caller): Yes. What I was wondering is if there is a biological basis to morality then there should be some people who are amoral. And I was wondering, are there any studies comparing people who are amoral because of some genetic defect to, you know, a moral person and seeing if there's any differences to try to find exactly what is the biological basis of morality?

Prof. PINKER: It's an excellent question and there are - it is a - there is a promising lead. The people who are often diagnosed as psychopaths or the related condition of anti-social personality disorder seem to fall into that category, they show no empathy, they often show cruelty even from the time they were children. They bully smaller children and torture animals, they have a great deal of difficulty empathizing and some of them commit heinous acts like bilking elderly people out of their life savings or raping a succession of women. There are some kinds of people with anti-social personality disorder who do have differences in their brain, in particular, in the parts of the brain that seem to light up when people ponder throwing the fat man over the bridge to stop the runaway trolley. And although no one has identified a set of genes that contribute to psychopathy and in some cases it's caused by a brain damage rather than by genes. I suspect that in 10 years' time, there will be a set of genes that are associated with a lack of conscience and in the extreme case an absence of conscience, as we see in psychopaths.

CONAN: Mm-hmm. David, thank you.

DAVID: Well, thank you. Bye-bye.

CONAN: And this last e-mail from Dave(ph).

(Reading) Humans often seem unable to weigh life equally in moral situations, for example the uproar over the death of Princess Diana is wildly disproportionate to the hundreds of thousands brutally murdered in Darfur. I'd like Steve's comments on why people can't recognize this is one life versus hundreds of thousands and the outrage appropriate to the scale of the issue?

And we're going to give you 30 seconds to answer that.

Prof. PINKER: It's a great question. It partly reflects the fact that authority tends to be moralized and people who have high status and power tend to be given a moral free pass. It's also the effect of just firsthand experience. We feel more empathy to individuals that we see and know about than to statistics of hundreds of thousands of people who we don't personally see or form bonds to.

CONAN: Steven Pinker, thank you very much for your time today.

Prof. PINKER: Thanks for having me.

CONAN: Steve Pinker is the Johnstone professor of psychology at Harvard University. He joined us from a studio there. And again, you can find a link to his article, "The Moral Instinct," on our Web site at

Coming up, NPR's Howard Berkes explains how the Mormons will choose a new leader and Massachusetts Senator Ted Kennedy's endorsement of Barack Obama to be the next president of the United States. Stay with us.

I'm Neal Conan. It's the TALK OF THE NATION from NPR News.

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