Daniel Kahneman On Misery, Memory, And Our Understanding Of The Mind

Mar 12, 2018

Economic theory rests on a simple notion about humans: people are rational. They seek out the best information. They measure costs and benefits, and maximize pleasure and profit. This idea of the rational economic actor has been around for centuries.

But about 50 years ago, two psychologists shattered these assumptions. They showed that people routinely walk away from good money. And they explained why, once we get in a hole, we often keep digging.

The methods of these psychologists were as unusual as their insights. Instead of writing complex theorems, Daniel Kahneman and Amos Tversky spent hours together...talking. They came up with playful thought experiments. They laughed a lot.

"We found our mistakes very funny," recalls Kahneman. "What was fun was finding yourself about to say something really stupid."

The insights that Kahneman developed with Tversky, who passed away in 1996, transformed the way we understand the mind. That transformation also had philosophical implications.

"The stories about the past are so good that they create an illusion that life is understandable, and they create an illusion that you can predict the future," Kahneman says.

Daniel Kahneman won the Nobel prize in 2002, and over the past 99 episodes of Hidden Brain, we've drawn extensively on research inspired by his work. This week, we celebrate our 100th episode by interviewing Kahneman about judgment, memory, and the mind itself. He spoke with us before a live audience at NPR headquarters in Washington, D.C.

Hidden Brain is hosted by Shankar Vedantam and produced by Parth Shah, Rhaina Cohen, Jennifer Schmidt, Matthew Schwartz, and Renee Klahr. Our supervising producer is Tara Boyle. Special thanks this week to Kara McGuirk-Allison. You can also follow us on Twitter @hiddenbrain, and listen for Hidden Brain stories each week on your local public radio station.

Copyright 2018 NPR. To see more, visit http://www.npr.org/.


This is HIDDEN BRAIN. I'm Shankar Vedantam. Economic theory rests on a simple notion about human beings - people are rational. They seek out the best information. They measure costs and benefits and maximize pleasure and profit. This idea of the rational economic actor has been around for centuries.


VEDANTAM: But about 50 years ago, two obscure psychologists shattered these foundational assumptions. The psychologists showed that people routinely walk away from good money. And they explained why once people get in a hole, they often keep digging. The methods of these psychologists were as unusual as their insights. Daniel Kahneman and Amos Tversky spent hours together talking. They came up with playful thought experiments. They laughed a lot.

DANIEL KAHNEMAN: We found our own mistakes very funny. What was fun was finding yourself about to say something really stupid.


VEDANTAM: This is Daniel Kahneman. The insights he developed with Amos Tversky, who passed away in 1996, transformed the way we understand the mind. That transformation had philosophical implications.

KAHNEMAN: The stories about the past are so good that they create an illusion that life is understandable. And that's an illusion. And that - they create the illusion that you can predict the future. And that's an illusion.


UNIDENTIFIED MAN: Professor Kahneman, your important insights...

VEDANTAM: Daniel Kahneman won the Nobel Prize in economics in 2002.


UNIDENTIFIED MAN: The new bridges between economics and psychology are attributed to your pioneering research.

VEDANTAM: Over the past 99 episodes of HIDDEN BRAIN, we have drawn extensively on research inspired by these two psychologists. So for HIDDEN BRAIN's 100th episode, we thought we'd invite a very special guest, Daniel Kahneman. We taped this interview before a live audience at NPR headquarters in Washington, D.C.


VEDANTAM: Danny, welcome to HIDDEN BRAIN's 100th episode.


VEDANTAM: So, Danny, as I was reading that introduction, I could almost see you cringing because you've spent a lifetime worried about overstatement and exaggeration and overconfidence and luck. And I'm wondering if we could just start there. If you were to look back at your own life, how much of your success would you attribute to talent and how much to luck?

KAHNEMAN: I mean, you know, some talent was really needed. And - but luck - you know, I can see so many points in my life where luck made all the difference. And mainly, the luck is with the people you meet and the friendships you make. There is a large element of luck in that. And my life was transformed by sheer luck in, you know, finding a partner, an intellectual partner, with whom we got along very well and we got a lot done.

VEDANTAM: Before we get to Amos, I want to talk about another person whom you met. This was in 1941-42. You're a very young Jewish boy living in German-occupied Paris. And one day, you're out beyond curfew. An SS officer spots you and runs up to you. What happens next?

KAHNEMAN: Well, he doesn't run up to me, but he beckons me to him. And I was wearing a sweater. I was - it was past the curfew, and my sweater had a yellow star on it, and so I was wearing it inside out. And then he called me. And he picked me up. And I was really quite worried that he might see my yellow star. And then he hugged me tight, and then he put me down. He opened his wallet, and he showed me a little boy. And then he gave me some money, and we went our separate ways.

Obviously, I reminded him of his son. And he - you know, he wanted to hug his son, so he hugged me. That's an experience that for some reason - you know, I mentioned it in my Nobel autobiography - but as illustrating a theme that was a theme in my family actually, in my mother especially - that people are very complicated. And that seemed to be an instance of something very complicated. And so it stayed that - you know, in that sense. It's a memory that was important to me.

VEDANTAM: So when an event like that happens, I can imagine most people just saying thank God and moving on, but you found it interesting partly because you said there's something interesting that happened here. And I - and from a very young age, it seems you were drawn to these curiosities about how the mind work.

In some ways, the SS officer was making a mistake. He was looking at you and drawing an association from you to - so to another child, maybe his own son. And, of course, in many ways, it was an error. It was - the mind was not working in a quote, unquote, "rational fashion," but it was more associative.

KAHNEMAN: The complexity was that it's the combination of somebody who must have done some very evil things and had thought some very evil thoughts and yet, he was hugging me. And, I mean, you know, that kind of complexity was everywhere. I mean, Hitler, you know, liked children and liked flowers and was very kind to some people. So - and we have a lot of difficulty putting that together with, you know, the things he did. But it - that complexity was always interesting.

VEDANTAM: At what point do you feel you became the person who was paying attention to his own thoughts? Because so much - so many of your early insights were developed obviously in experiments that you ran on people, but you were also observing the way your own mind worked and observing, if you will, oddities in the way that your own mind worked. Was that always the case with Danny Kahneman?

KAHNEMAN: I think so. I mean, I - yeah, I wrote a psychological essay when I was 11. So I, you know, it was short.


KAHNEMAN: But, well, you know, I'll tell you what the essay said, actually, because it shows quite a few things, I think. But so my oldest sister was taking exams in philosophy, and I had read some Pascal. And, you know, Pascal explained why - gave proofs of God's existence. Pascal said that faith is God made sensible to the mind. And I, you know, a little boy of 11, very pompous, of course, I said, how right, you know.

And then the psychological part was I said but this is very hard. The experience of faith is very rare. And so that's why we have churches and organs and pomp to sort of - and I called it air zaps - I mean, the sort of fake experience - generated, fake experience. So that was - you know, that was psychology. And obviously, you know, that's what interested me then, and it's interested me since.

VEDANTAM: Later on, as you were working as a professional psychologist now, you made, in some ways, a career of thinking about how your own mind worked. And I'm fascinated by this idea because in some ways, a lot of people look at how their minds work and they're defensive about it, or they defend how their minds work. Or they say, no, I - what I did made perfect sense. And instead, in some ways, I think your humility - and clearly, it's a temperamental quality of yours - helped you to sort of see some of these oddities and think about why they happen.

KAHNEMAN: That's not quite the way it happened, actually. I had my friend and collaborator - Amos and I, we worked together on that. And nobody ever accused him of being humble. He was not.


KAHNEMAN: And - but what the two of us did - we found it - we found our own mistakes very funny. And so we had a lot of fun just exploring what is our first impulse when it's wrong. And that, you know, that can be an endless source of fun. And there was no particular humility in it. On the contrary, in a way, that is we never thought that people are stupid because we were finding all of that in ourselves, and we didn't think we were stupid. So there was very little humility there. What there was was irony. And the irony was part of the fun.

VEDANTAM: What was funny about it? I can see why it was interesting or why it was curious. But I understand that when you and Amos worked together, there was just endless amounts of hilarity.

KAHNEMAN: There was a lot of laughter. And, you know, what was fun was finding yourself about to say something really stupid and, you know, having - and sort of holding back because you know better. But it's that impulse to say things that, you know, that are without basis or that are purely associative or that - and really doesn't matter, you know, how intelligent you are or how educated you are. There are those intuitions or those thoughts that come from somewhere that come very reliably and predictably and that are wrong. So that - you know, it's a big field to study.

VEDANTAM: Meeting Amos was clearly a stroke of luck. I mean, I don't think your life would have taken the same path that it did...

KAHNEMAN: Certainly not. I mean, you know, it's rare, really. But he was exceptionally smart and very, very quick. And there is - when you have two people who are working together who really, in a way, love each other's mind and admire each other's mind, that is very special because it gives you a sort of confidence when the other - you say something and the other person sees something in it that you haven't seen.

And this is very rare, this kind of mutual trust and looking for what's interesting and good in what the other person is saying. And both he and I sort of made - we were both quite critical people, I mean, he even more than I. But we made an exception for each other, and that was a joy.

VEDANTAM: So many of your early insights were based on thought experiments where you came up with sort of very simple questions that you posed to both yourselves and to other people. Why these thought experiments? And when we talked a few days ago, you actually said that this is part of the reason you think that your work appealed to a larger audience because even if the ideas were complex, the questions were inherently interesting and accessible.

KAHNEMAN: Well, that's a stroke of luck, really. And there's a famous psychologist, Walter Mischel, who wrote a book on the marshmallows test a few years ago. And in 1964, he published his dissertation. And his dissertation was done in Jamaica with small children. And he asked those children two questions. And one of them was there is a fairy who can make of you whatever you want to be. What do you want to be? And the other question was you can have this lollipop today or two lollipops tomorrow. What do you prefer? Now, these two questions were correlated with everything in sight. I mean, they were correlated with how bright the child was, with how educated the parents were. And I just fell in love with that idea, the psychology of single questions. And I looked for ways to do that sort of thing. And the work with Amos on judgment turned out to lend itself to just that, that is there is a single question that elicits a funny thought, and it makes a point.

And, you know, the first place, we were very lucky in the truest of problem. There are just no other problems in psychology that lend themselves to that sort of thing, that you can involve the reader and present questions to the reader, and you make the reader think. So you can do that in vision. And everybody here, I'm sure, has had the introductory psychology at some point. And there are those demonstrations of perceptual effects, like figure-ground or...

VEDANTAM: Optical illusions.

KAHNEMAN: ...Perceptual organization or - and they are on the page, and that's the phenomenon. You are your own subject. Now, you can do that on vision. You can do that on judgment, which is the field that we did it in, and that's it. You know, you can't do it on self-control. You can't do it on many other things. You can't do it on personality studies. So when I was talking of luck, that's luck, I think, to hit on something that, you know, we happen to be prepared for and that is uniquely - you know, that lends itself uniquely to something that creates experiences in readers, you know, sheer luck.

VEDANTAM: So after many, many years of collaboration together, your partnership with Amos floundered, I think it's fair to say. I'm wondering whether you've given the same thought to why that happened that you gave to other things that your mind does and whether those insights - I mean, so many of your insights about how your mind has worked have helped the rest of us. Is there anything here that could help the rest of us think about collaboration and partnership?

KAHNEMAN: No. I mean, you know, there's natural stresses in collaboration. The world is not kind to collaborations. You know, when you have two people who are reasonably talented, and they work together, and they overlap closely, then - I'm quoting Amos - he said, "when I give a lecture, people don't think I need anybody else to do the work." And that was true, to some extent, in me as well.

And so that creates stresses. And, of course, I've given a lot of thought to it. We were fortunate that we went on as long as we did. We were fortunate that we remained friends, you know, even when there were stresses in the collaboration and in the friendship.

VEDANTAM: I remember research that Abraham Tesser did many years ago where he looked at couples or other pairs of people who were very similar to one another. And one of the things he found is, of course, the closer in similarity people were, the more they reached for the same goal. You had, let's say, a couple who are both writers. The success of one person tended to make the other person feel smaller. Even though you're happy for your partner, there's a part of you that says, why can't I have the success that my partner has? And it's a very human thing, of course.

KAHNEMAN: Yeah, of course. You know, and it's, of course, especially true if it's joint work, which they are. So this is - you know, there's really a dynamic, and it's - I would say we were just about perfect for, you know, 10-12 years, which is a very long time.

VEDANTAM: When we come back, what Danny and Amos discover together. Stay with us.


VEDANTAM: For HIDDEN BRAIN's 100th episode, I interviewed Daniel Kahneman. He's the author of the book "Thinking, Fast And Slow." In the 1960s, Danny spent a summer with a group of eminent psychoanalysts at a treatment center in Massachusetts. The center had a routine. A patient was examined for a month by multiple experts and then everyone came together to do a case study. They reviewed notes and interviewed the patient together. One particular case left a strong impression on Danny.

KAHNEMAN: In the morning, we learned that the woman, the young woman about whom we'd written the report, had taken her life. And they did a very brave thing. They ran the case study. And I was deeply impressed, both by the honesty of what they did, but what they were trying to do, they were seeing signs that they had missed. And it was, you know, in retrospect, obviously. This was hindsight at work. I mean, now you know what's happened. So you're seeing signs and premonitions and people are really feeling guilty. I saw her on the stairs and she looked strange. And, you know, why didn't I stop to inquire? I mean, you know, people look strange all the time. But, you know, when somebody - so yeah. That was - that was an important episode.

VEDANTAM: And, of course, what this episode reveals is how once an event happens, we trace back a story about how that event came to be. And, of course, in journalism, we do this all the time. You know, I remember after the 9/11 attacks, we spent years sort of deconstructing all the errors that were made and drawing a pattern. And when you see that pattern laid out, you have to say, well, those people must have been really dumb because it's so obvious that there was a pattern that led to the 9/11 attacks.

KAHNEMAN: Yeah. This is hindsight. And it's one of the most important phenomena, truly, in psychology - in the psychology of judgment because you understand the past. And the past surprises stop being surprising at the moment they happen. You know, then you have a story. And you shouldn't have been surprised. And when you reconstruct it, you also reconstruct wrongly what you believed at the time. So you minimize - you reduce the surprise. So not only was it inevitable, but also I almost - I really sensed it, so, you know.

Now, where this goes really wrong is that the stories about the past are so good that they create an illusion that life is understandable. And that's an illusion. And they create the illusion that you can predict the future. And that's an illusion. And it's maintained by hindsight. So hindsight is a central phenomenon, really.

VEDANTAM: And, of course, the errors we make eventually lead to prospect theory, which was the work which you were cited for in the Nobel Prize, among other things. If you were to explain prospect theory to an eighth grader, is there a way to do that?

KAHNEMAN: Well, it's very easy to explain. It's much harder to make it interesting. And...


KAHNEMAN: ...It's the theory that dominated thinking when we wrote and, to a very large extent, still dominates economic thinking. It was formulated first in 1738, so it's been around a long time. And what it says is that when you're looking at a gamble, what you are evaluating is you're evaluating two states of wealth - your wealth if you will win and your wealth if you will lose. And then if you're offered a sure thing, your wealth if you get that sure thing. And for 200 and, you know, 60 years and so, people accepted that theory.

Now, the theory really is - it doesn't make sense if you stop to think about it. People don't think of gains and losses as states of wealth. They just don't. They think of gains and losses as gains and losses. That was the fundamental insight of prospect theory. So, you know, you could ask that, you know, you get the Nobel Prize for that.


KAHNEMAN: And you do in a certain context because - if it surprises people.

VEDANTAM: One of the things you say in the book is our comforting conviction that the world makes sense rests on a secure foundation - our almost unlimited ability to ignore our ignorance. And, of course, you've made - spent a lifetime exploring the depths of your ignorance and all of our ignorance. But in many ways, there's something deeply human about this. To see the world as being chaotic and unpredictable and noisy is fundamentally unsettling. And it's easier to see the world as understandable and comprehensible and that fits in a story.

KAHNEMAN: Well, it's not - you know, we really have no option. I mean, the mind is created to make sense of things. I mean, vision makes sense of things. We see objects. We see objects moving. And it's the same with judgment and thinking. We have to make sense of things. And we can't do otherwise. So it's not, you know, that we would be unsettled if we did otherwise. We can't. We make sense of things. That's the fundamental - we are sense-making organisms.

VEDANTAM: And, of course, it's worth pointing out that even though this leads to errors, it's also the case that, much of the time, this is enormously valuable and our sense-making ability is - actually works great, that it actually allows us to navigate the world successfully.

KAHNEMAN: Of course. I mean, you know, we're right almost all the time. I mean, you know, we couldn't survive if we weren't right almost the whole time. We make interesting mistakes. And sometimes they're important mistakes. But mostly, we're very well-adapted to our environment.

VEDANTAM: So when you think about news events - you know, if I tell you there are 19 hijackers who have flown planes into major buildings, and then we go back and we get biographical sketches of these people and we understand their ideologies and, you know, it activates things in our minds because of course there are these agents that are doing these things to us. And, you know, we then spend hundreds of billions of dollars trying to combat terrorism. And you say, OK, that makes sense. This was a major threat.

We've dealt with it. But let's say you have another threat over here where I tell you that in 80 years or 100 years, the temperature might rise five degrees. And as a result of this, the oceans might warm a little bit and sea levels might rise by two or three inches. And as a result of this, models predict that climate events will become more serious - at least, according to the models. But you have to understand probability. And in order to try and head that off, you actually have to take very painful steps right now - maybe driving your car less, maybe living in a smaller house, all kinds of things that are painful in the here and now - for something that seems difficult off in the distance and requires you to really understand statistics and probability. You've actually called climate change, in some ways, sort of a perfect storm of the ways in which our minds are not equipped to deal with certain kinds of threats.

KAHNEMAN: I mean, it's really - if you were to design a problem that the mind is not equipped to deal with, you know, climate change would fit the bill. It's distance. It's abstract. It's contested. And it doesn't make - it doesn't take much. If it's contested, it's 50/50, you know, for many people immediately. You know, you don't ask, what do most scientists do? Which side of the National Academy of Sciences - that's not the way it works. You know, some people say this, other people say that. And if I don't want to believe in it, I don't have to believe in it.

So it's - I'm really - well, I'm pessimistic in general. But I'm pessimistic in particular about the ability of democracies to deal with a threat like that effectively. If there were a comet hurtling down toward us - you know, an event that would be predictable - within a day, we'd mobilize. So it's not even that it's distant in time. If it was going to affect our children, we'd mobilize. But this is too abstract, possible, contested. It's very different. We can't - we're not doing it, in fact.

VEDANTAM: So besides being pessimistic, does your research and understanding of this phenomenon give you any insight into how we should maybe talk about climate change and what we can do?

KAHNEMAN: Well, I think scientists, in a way, are deluded in that they have the idea that there is one way of knowing things. And it's you know things when you have evidence for them. But that's simply not the case. I mean, you know, people who have religious beliefs or strong political beliefs. they know things without having, you know, compelling evidence for it. And so there is a possibility, you know, of knowing things, which is clearly determined socially. I mean, we have our religion and our politics and so on because we love it - we love or used to love and trust the people who held those beliefs.

There is no other way to explain, you know, why people hold to one religion and think other religions are funny, you know, which is really a very common observation. So the only way would be to create social pressure. So, for me, it would be a milestone if you manage to take influential evangelists, preachers, to adopt the idea of global warming and to preach it. That would change things. It's not going to happen by presenting more evidence. That, I think, is clear.

VEDANTAM: When we come back, we'll talk about happiness, memory and noise. Stay with us.


VEDANTAM: This is HIDDEN BRAIN. I'm Shankar Vedantam. Daniel Kahneman won the Nobel Prize for a series of ideas that helped develop the field of behavioral economics. Danny, I don't know how you got an ethics panel to approve the study, but it's one of my favorite studies of all time. Tell me about the colonoscopy study and the peak-end rule.


KAHNEMAN: Well, the colonoscopy study was devised to test an idea that when people form a memory of an episode or an impression of an episode that had a certain duration, that actually they completely neglect the duration. And what they are sensitive to are illustrative or crucial moments. And in particular, when it's a painful experience, it's the peak of the pain and it's the end of the pain. It's how much pain you're at in the end. So that was a theory for which we had other evidence.

And my friend, Donald Redelmeier, who was a physician in Toronto, he volunteered to create a study around that. So the study was run on people who had a colonoscopy, which at the time was very painful. I mean, for those of you who, you know, have not reached the age of colonoscopy, it won't be painful when you have it.


KAHNEMAN: But at that time, it really was. So people had a colonoscopy. And then half of them, you know, it ended when it ended. But for half of them, they left the tube in for another minute or so. Now, this is not pleasant. Nobody would volunteer to have the tube in for another minute. But it improves the memory very significantly because it's less painful than what went on before. It's not desirable. You wouldn't choose it. But it makes a difference between the really aversive memory, which you have - when they pull the tube at the moment of high pain, the whole thing is very bad.

But if you end on a gentler note, even if it's still painful, the memory improves. Memory wasn't designed, you know, to measure ongoing happiness or to measure total suffering. For survival, you really don't need to put a lot of weight on duration - on the duration of experiences. It's how bad they are and whether they end well. I mean, that is really the information that you need for an organism. And so there are very good evolutionary reasons for the peak and end rule and for the neglect of duration. It leads to, you know, in some cases, to absurd results.

VEDANTAM: So if you were a policy maker, I feel like this is a real ethical dilemma. So let's say, for example, I'm running a hospital. I think the colonoscopy study, or versions of it, have later found that if you actually give people the painful experience followed by the less painful experience, they are more likely to come back for the next colonoscopy because their memory of the colonoscopy was less painful. So you could argue, from a public policy standpoint, if you want people to get tested, the right thing to do is to extend their pain in order that they will remember the pain as being less and come back more often. However, also from an ethical point of view, you could argue that subjecting people to more pain than you need to subject them to is unethical. So what should we do?

KAHNEMAN: That one is easy.



KAHNEMAN: I mean, you know, there are harder versions of it. But that one is easy because you would never frame it that way. You would just tell - you would just tell the people who are doing the procedure, be very gentle at the end. You know, be slow and gentle at the end. And, you know, that sounds like a good thing. And it's good for policy. And it will get more people - it will leave better memories. It will - more compliance and so on. So there are ways sometimes of not presenting quite as sharply as you did.

VEDANTAM: What would be a more difficult ethical dilemma that I didn't think of that you could place to your - apply to yourself?

KAHNEMAN: Well, I think that if real suffering is involved, you know, somebody in pain, I'd say you can be in pain and barely conscious, or you can be in pain and they will eliminate the memory at the end. So what is the - what - how much weight should you give to pain that the patient might be screaming but will not remember? You know, that's an ethical dilemma.

VEDANTAM: And, of course, this does have all kinds of other implications. You've done some work looking at, you know, if you could go on a vacation, but you couldn't take photographs on the vacation, how would you think about the vacation? In other words, you essentially have these two models of how the mind works. There's a mind that experiences life and there's a mind that remembers life, and these two minds don't always agree with one another.

KAHNEMAN: Well, I mean, they have different interests, in a way. I mean, so I spoke of the experiencing self, which is, you know, the one that lives moment to moment. And the remembering self is the one that keeps score. And the scores that are generated are generated, again, by rules, such as the peak-end rule and so on. And so sometimes you can see that experiences are a very different duration, and what - how do they matter? Or what is the value that you should attach to an experience that you will not remember or that somebody will not remember? So my question in that context was - I mean, consider your plans for your next vacation.

And now imagine that, at the end of the vacation, they will destroy all your pictures and they'll give you an amnesic drug so that you won't remember a thing. Now, would you change your vacation plans if you knew that? And many people would, actually, because I think many people go on vacations to create memories for future consumption, which doesn't always happen. I mean, in my case, it never happens.


KAHNEMAN: I never look at pictures. But that's a dilemma.

VEDANTAM: So you conducted a study, I remember, a few years ago. I think it was published in the journal Science where you evaluated how happy parents felt as they went through their days, and you - there's two ways you can, of course, ask the question. You can ask parents, how happy are you with parenting? And many parents will say, it's the best thing they ever did. But then you can also ask parents on a moment-to-moment basis as they are parenting how they feel, and the answer turns out somewhat differently.

KAHNEMAN: Well, yeah. I mean, it's - you know, it turns out that parenting, if you really take the experiencing view of it, then, you know, it's like washing dishes - you know, maybe a little worse often.


KAHNEMAN: And then - you know, and then it has its moments. And it's the peak moments that people remember. And when people remember the peak moments, it makes the whole thing worthwhile. So it changes the meaning of the whole experience. So that was a much-contested finding, very unpopular finding, but a very strong finding.

You know, if you look at the experiences, people have more fun with their friends than with their spouses, you know, quite a bit. And if you were trying to make - to increase the happiness of the experiencing self, you would do very different things than people do because what people typically do, they try to satisfy their remembering self. And maximizing the happiness of your experiencing self would make you more sociable, less ambitious. It would make you spend a lot more time with people that you love or like or enjoy because it's very largely social. So there are very important implications of that distinction.

VEDANTAM: Is there any insight that someone can draw from this work about whether they should become a parent, given this discrepancy between the remembering self and experiencing self? And I should remind you before you answer that your daughter is in the audience here with us.


KAHNEMAN: I have never met - almost never met people who regretted having had their children. So if you measure a thing by the remembering self, that's the - really the only way. The point is that the experiencing self doesn't make decisions. All the decisions are made by the remembering self. And the remembering self never regrets having had children. So, you know, from that point of view the answer is clear.

VEDANTAM: Well, we're in the process right now at HIDDEN BRAIN of hiring someone. And in fact, we just conducted two interviews today and we have a couple tomorrow. And as I was doing the interviews, I was thinking about some of the work that you've done. In some ways this was your earliest work going back many, many decades, looking at how you can reduce errors in the interview process. And I don't know whether you think of it as bias or think about it as noise, but either way it leads to flawed outcomes. And you came up with a technique that could address it.

KAHNEMAN: Yeah, I actually - I did come up with the technique a little more than 62 years ago actually. I was an officer of the Israeli army. It was 1954. The Israeli army was very young. It was 1956, actually. And I set up an interview system which is a template for a lot of what is going on and is certainly a template for the way I think decisions should be made. I haven't thought of that for many years, but - and the template is you have a problem. You need to evaluate people. Break it up into dimensions. You know, what sounds elementary. And I'm not going to say anything very surprising.

Make judgments of each dimension independently of all the others. That independence is essential. Don't form a general impression until you have all the information. Delay intuition. Don't give it up unnecessarily - delay it. And the results are just better when you do things that way. And I think that probably is very general as a way of thinking about judgment and decision-making. It's a way of reducing noise, of increasing reliability. And it's not very costly. And I'd like to promote it.

VEDANTAM: So of course the idea, if I understand correctly, is you score people on different criteria, give them a ranking so that you're evaluating it. But there's also an interesting piece of advice which I understand they still offer in the Israeli army when you're doing these evaluations, a final piece of advice after you've done the calculations. What is that advice?

KAHNEMAN: Yeah, well, that's - So I set up that interviewing system. I was 22 years old. And the people - the interviewers, who were 19 years old, they really didn't like that suggestion. They - what they really wanted was to have a heart-to-heart conversation and then to form a general impression of how good a combat soldier that individual would be. But they said, you are turning us into robots. And they had a point.

And then I told them, OK, you know, I'll compromise. You do it my way, the interview. You run the whole interview just and you generate those scores independently, fact-based and so on. Don't think of anything until the end. And in the end, close your eyes and give a score. How good a soldier will that person be? Now, much to my surprise, that intuitive score is really, very good. I mean, it's as good as the average of the six traits. And it's different, so it adds content. So having an intuition, if you delay it, it's quite good.

The kicker of that story was that about 50 years later or so I got a Nobel Prize. So for a short time I was a celebrity in Israel. And they took me to the army, to my old base. And they explained how they were doing the interview because they were still using that system essentially with very little change. And then the commander was telling me - and then she said, and then we tell them, close your eyes. So that thing had lasted for 50 years....


KAHNEMAN: ...That's that expression, so...

VEDANTAM: So what I love about that - it's not so much intuition versus bias, but it's more maybe by just delaying intuition the intuition gets better. And of course if you don't do the detailed analysis, you still have an intuition that feels very powerful. And your ignorance is sort of papered over by this tendency of the mind.

KAHNEMAN: And, you know, intuition is compelling as such. I mean, you know, we have the intuition. Almost by definition we trust it. And so delaying this and remaining very close to facts as you collect your separate dimensions is really, very useful. And it permits an intuition that is well-informed because normally we form intuitions very quickly and then we spend the rest of the time confirming that, yeah, this intuition was right. That, by the way, is a fact. It's been studied that way in interviews. People form impressions in the first minute or two and they spend the rest of the time testing that they're right and of course confirming that they're right. So...

VEDANTAM: So this was clearly an example of how you came up with a mechanism in some ways to overcome how the mind works. But on many, many other fronts it seems like the biases, errors that you've discovered, even yourself - you say that you don't necessarily - you're not the master of those biases after studying them for more than half a century.

KAHNEMAN: Yeah. I mean, even myself. I mean, I'm considered one of the worst offenders on many of these mistakes. So, you know, I'm overconfident when I really preach against that. And I make extreme predictions and I preach against that. But, you know, the - you know, some people read "Thinking, Fast And Slow" in the hope that reading it will improve their minds. I wrote it and it didn't improve my mind.


KAHNEMAN: So it's not - those things are, you know - they're deep and they're powerful and they're hard to change.

VEDANTAM: Danny, yesterday was your 84th birthday. Happy birthday.


VEDANTAM: You've studied a great number of different things over the years. And you tell me that one of the things that you're actually interested in studying is the subject of misery. Much more than happiness, you're fascinated by misery. Now, of course I can just put this down to the pessimism that clearly you've demonstrated for a long time. But you actually say you can draw more specific conclusions and there are takeaways from studying misery than from studying happiness.

KAHNEMAN: Yeah, I'm actually - you know, I contributed to what is called happiness research. But I'm really disturbed by it. And I'm disturbed by positive psychology in part because I think that making people happier is - you know, could be important, hard to do. It may not be society's business to make people happier, but reducing suffering - that's something else. It's easy to agree that this is important. It's easy to agree that society should be involved.

Furthermore, it's easier to measure misery than to measure happiness. And what we can do about it is clearer than what we can do to enhance happiness. So from all these points of view I think that - and again, you know, it's a matter of semantic luck. You know, we speak of length and not of shortness. And so we speak of happiness and not of - and not of the other side, of unhappiness. But if you focus on unhappiness and misery, you end up doing very different things, thinking very different thoughts and taking very different actions, which I think we should do.

VEDANTAM: So you've been a wonderful sport, Danny, and I'm really grateful for you for coming down. And I'm almost a little shamefaced about doing what I'm about to do right now, which is I'm wondering if we can increase your happiness just a tad. But it might increase your misery by singing "Happy Birthday" to you.


VEDANTAM: You're one of HIDDEN BRAIN's heroes, and we feel that it's really appropriate to end with that. So on the count of three. (Singing) Happy birthday...

UNIDENTIFIED CROWD: (Singing) Happy birthday to you. Happy birthday to you. Happy birthday, dear Danny. Happy birthday to you.

KAHNEMAN: Thank you.


VEDANTAM: Danny Kahneman, thank you for joining me today on HIDDEN BRAIN's 100th episode.

KAHNEMAN: My pleasure.


VEDANTAM: This episode of HIDDEN BRAIN was produced by Rhaina Cohen and Kara McGuirk-Allison and edited by Tara Boyle. Our team includes Jenny Schmidt, Renee Klahr, Parth Shah and Matthew Schwartz. Our engineers are Andy Huether and Neil Travault (ph).

Many months ago, we started a feature in our credits where we thank someone whom we call an unsung hero. This person was someone who worked their magic behind the scenes without whom the episode could not have come together. We have called out many unsung heroes in the past months. Our unsung hero this week is Lenore Shoham. Lenore is Danny's daughter, and she's here in Washington with us today visiting from Israel. A few hours ago, as news broke of a major snowstorm menacing the East Coast, Lenore had a difficult decision to make. She and Danny were planning to see a Paul Taylor show in New York tomorrow. If they were to get to New York safely before the storm hit, they would have had to leave three hours ago. We are truly grateful to you, Lenore. We literally wouldn't be here without you.


VEDANTAM: I'm Shankar Vedantam. See you next week.

(APPLAUSE) Transcript provided by NPR, Copyright NPR.