Placeholder Image

字幕列表 影片播放

  • >> John Boyd: All right. I'm John Boyd. It is my great pleasure to introduce Professor

  • Kahneman today. And I just want to give you a brief background on his outstanding career.

  • He started in 1954 received his bachelors in experimental psychology and mathematics

  • from the Hebrew University in Jerusalem. In 1961, he was awarded his Ph.D. from University

  • of California Berkeley right across the bay in Experimental Psychology. In 1979, he and

  • his coauthor Amos Tversky published their seminal paper on Prospect Theory which started

  • to change the way people reframed the argument around gains, losses, and decision-making

  • under uncertainty. Several years later in 2002, Professor Kahneman was awarded the Nobel

  • Prize largely on the work of Prospect Theory of. And Nobel Prize isn't always impressive;

  • his perhaps more so because there isn't a Nobel Prize in psychology. He had to win his

  • Nobel Prize in economics. And as far as I know, there's only one other person, one other

  • psychologist, who's won a Nobel Prize and that's Ivan Pavlov. He may be a physiologist,

  • we could argue about that. Years later, in 2007, Psychologist tried to reclaim Professor

  • Kahneman as one of their own when the American Psychological Association awarded him Lifetime

  • Distinguished Contribution Award. And today he is a Senior Scholar at the Woodrow Wilson

  • School of Public and International Affairs at Princeton University and he's here to talk

  • about his new book Thinking Fast and Slow. Now Google's mission which we all know is

  • to take the world's information and to make it more useful and universally accessible.

  • And all information, all knowledge, is important, but I think some again is more important than

  • others. Because the information that he'll present today I think it's very personal;

  • it's about each of us. And, if you'll listen carefully it's going to change the way you

  • think about yourself and the world around you. So please join me in welcoming Professor

  • Kahneman to Google.

  • [Applause]

  • >> Kahneman: Thank you. Well, I think intuition has been discussed a lot in recent years and

  • I'll be talking about intuition. There are two camps in this discussion naturally there

  • is the pro and the con. And of course, many people here will have read Malcolm Gladwell

  • Blink which although it's not unconditional defense of intuition, it certainly gave people

  • the impression that sometimes we magically know things without knowing why we know them.

  • Within the discipline of psychology and the decision making there is a group and it is

  • headed by a very interesting figure called Gary Kline who wrote a book that I recommend.

  • Its Sources of Power is one of his books that I would recommend the most warmly. And they

  • are great believers in expert intuition. The other side there are skeptics about intuition

  • in general and including expert intuition. And I have long been counted as one of the

  • skeptics because my early work with Amos Tversky was about intuitive errors and flaws and biases

  • of intuitive thinking. Today you find that discussion in many places and for example

  • in medicine among the popular writers; two writers both of whom write for the New Yorker,

  • Jerome Groopman and Atul Gawande. They clearly differ. Atul Gawande is in favor of formal

  • systems, very skeptical about human judgment and wanting to prove all the time and Jerome

  • Groopman being in fact, although he doesn't quite admit he really likes good old fashioned

  • medical intuition. Of course he likes physicians well-educated. But he doesn't like formal

  • system and the issue in medicine is "What are the role of evidence based medicine and

  • how do you allocate that with the function of intuition?" The background actually, part of the background for what

  • I'll talk about today is a strange collaboration in which I engaged with about eight years

  • with Gary Klein, whom I mentioned. He is a guru of a group of people who really, I wouldn't

  • say they despise what I do but they certainly don't like what I do because they think that

  • the emphasis and biases of judgment has drawn an unjustly unfavorable picture of the human

  • mind. And by and large I am inclined to agree. Seven or eight years ago I invited him and

  • we worked together for a number of years trying to figure out where is the boundary? Where

  • is intuition marvelous and where is it flawed? And I think we can tell. And we wrote a paper

  • at the end of six or seven years with a lot of vicissitudes that we went through since

  • we basically don't agree. We wrote a paper the title of which was A Failure to Disagree,

  • because on the substance I think we know and we both agree where you can trust intuition

  • and where you cannot. Emotionally we haven't changed. He still hates the biases and doesn't

  • think that errors of experts are very funny and I think that errors of experts are quite

  • funny [laughter] so that's a difference right there. There are two modes of thinking that

  • all of us are familiar with. And there is one mode, one way for thoughts that come to

  • mind and listen to this. You know about this lady that she's I think adjust as quickly

  • as you know her hair is dark. And it's interesting to dwell a bit about this. It is this is not

  • something that the judgment that she is angry, the impression that she is angry. Doesn't

  • feel like something you did. It feels like something that happens. It happens to me.

  • We have the basic experience is a passive experience in those judgments. And that is

  • true of perception, when we see the world we don't decide to see it. It is true of impression.

  • And it is true in general what we call intuitive thinking. It just happens. It comes from somewhere.

  • And we are not the author of it. Now, there is another way that thoughts come to mind

  • and here I suppose essentially nothing came to your mind, but the answer is 408. To produce

  • the 408, requires a completely different kind of operation. You have to retrieve the program

  • that you learned in school. The program consists of steps. You have to go through the steps.

  • You've got to pay attention successively to partial products and so on. And keep things

  • in mind and keep the whole program in mind. This is how it works. This is something that

  • you do. It is not something that happens to you. And there are many indications that this

  • is how it works. One is that Physiology indicates and this is how it works: pupil dilates. This

  • is something that I studies many, many years ago that people really on a program like that

  • if you're on a problem like that if you're going to do it in your head, your pupil will

  • dilate. The area will increase by about 50% as soon as you engage in that. And it will

  • stay dilated as long as you're working and it will sort of collapse back to normal size

  • either when you quit or when you find the answer. So this is another way thoughts come

  • to mind. And this is definitely not the intuitive way. Here we are we feel a sense of urgency.

  • We feel something deliberate is happening and a very important aspect of it this is

  • effortful and what psychologists mean by effort is basically, if you want the quick introduction

  • to what effort is, this is something you cannot do while making a left turn into traffic.

  • You cannot do it and you shouldn't try. And the reason is that there is limited capacity

  • to exert effort. And if you are engaged that capacity or those resources at one task less

  • is available for another task. Now, there is another function of System 2. And here

  • I'm going to tell you a riddle. Most of you are familiar with it. A bat and a ball together

  • costs 1.10. The bat costs more than the ball. Of course how much does the ball cost? How

  • many people know this riddle by the way? Oh, okay. So it's still usable. The point about

  • this riddle is that the number came to your mind. And the number is ten cents. And everybody

  • just, I think. Maybe here they're exception, very few exceptions. People confess that the

  • number ten cents immediately came to mind. Now, it's wrong. Ten cents and dollar 10 is

  • a dollar 20. The solution is five cents. What is interesting here is that at Princeton,

  • at MIT at Harvard and I don't know about Stanford or CalTech about 50% of students asked this

  • question of undergraduates say ten cents. And we learn something very interesting when

  • somebody says ten cents. We learn that they didn't check because if they had checked,

  • they wouldn't say ten cents. So, there is a sense of confidence that people have that

  • these people in particular have and it brings us to another function of what I'll call System

  • 2. System 1 is the intuitive one; they perform those automatic and activities and System

  • 2 is the effortful one the one that the deliberate one. And the reason that I classify this as

  • System 2 operation is that self-control and controlling your attention and deliberate

  • exertion of effort are impaired when by other activities. So, if for example, a trivial

  • example, if somebody is asked to retain seven digits in their head and you then give them

  • a choice between chocolate cake, sinful chocolate cake and virtuous fruit salad they're more

  • likely to choose the chocolate cake than they would if they didn't have seven digits in

  • their head. It takes effort to control your impulses even such mild impulses as a preference

  • for chocolate cake. So you should be aware of that difference between System 1 operations, the automatic ones and

  • System 2 operations, the deliberate ones, it comes very clearly when in driving. So

  • driving is a skill. And any skilled activity measure of skill is that things begin to happen

  • automatically. So you can drive and conduct a conversation. You cannot make a left turn

  • into traffic, but by and large, we can drive and talk. So driving is largely automatic.

  • Braking, when there is any sign of danger, braking is completely automatic. That is,

  • you can notice while you're braking, but you first respond so that the response is immediate,

  • it is fully automatic. Now, in some places, not here where people drive in snow or ice,

  • they learn about skids. And then, occasionally, you'll find yourself as a driver in a skid.

  • And then System 2 will be mobilized because in a skid you're not supposed to do anything

  • that comes naturally to you. You shouldn't brake and you shouldn't steer away from the

  • skid. You should leave the brakes alone and steer into the skid, completely non-intuitive.

  • Now, when people have a lot of practice with skids that too becomes automatic. So one thing

  • that we can tell about System 1 and System 2 those two types of operations, is some of

  • the basic innate operations, functions that we have such as having emotional reactions

  • to things, all this is System 1. We don't choose to do it. It just happens to us. But

  • also System 1 is where skill is. That is when we get to be skilled at something it becomes

  • automatic and it demands your resources and we get to be very good at it. Now, the issue

  • of intuition and here I'm not sure, but I suspect that Malcolm Gladwell really did us

  • a disservice by giving us a sense there is magic to intuition. There really is no magic

  • at all and we should understand how it works. Intuition and Herbert Simon who was Psychologist

  • then and economist and a political scientist Nobel Laureate, Herbert Simon gave a very

  • good definition about what intuition is. It is simply recognition. There is really no

  • difference between the physician recognizing a disease, you know, a particular disease

  • from a facial expression or something and a little child learning, pointing to something

  • and saying doggie. The little child has no idea what the clues are but he just said.

  • He just knows this is dog without knowing why he knows. And once you think about it

  • this way, this really demystifies intuition to a very considerable extent. And it also

  • leads you to sort of a solution to the problem Gary Klein and I were trying to solve. When

  • can you trust intuition and when can't you? And then it becomes an issue of is the world

  • regular enough so that you can learn to recognize things? Or and then did that particular individual

  • have an opportunity to learn the regularities of the world? And so, the world of chess players

  • is highly regular. And statistically, the world of poker players is very regular. So

  • there is an element of chance, but there are rules and the mind is so set that if there

  • are rules in the environment and we're exposed to them for a long time, and we get immediate

  • feedback on what is right and wrong, or fairly immediate feedback, we would acquire those

  • rules. So all of us have expert intuition even if we are not physicians and we're not

  • master chess players. I recognize my wife's mood from one word on the telephone. You know,

  • most of you can do that. There's people that you know very well. All of us recognize dangerous

  • driver on the next lane. And you know we get cues and we don't necessarily know what is

  • the cue but this person is driving erratically and could do something dangerous. And this

  • is a lot of reinforced practice and we're very good at that. We can learn about those,

  • there are differences. Among experts, among professionals, in the level of expertise that

  • they have and they depend in the level of intuitive expertise that they can develop.

  • So for example, compare anesthesiologists to radiologists. Anesthesiologists get very

  • good feedback, an immediate feedback whenever they do anything wrong. You know they have

  • those measurements in real time. Radiologists get really miserable feedback about whether

  • they're right or wrong. So you could expect an anesthesiologist to develop intuition much

  • more than you would expect radiologist to develop intuition. And so, that is part of

  • the answer about intuitive expertise. We don't need to disagree about that because we know

  • pretty much when intuitive expertise is likely to develop. And as I said, we also that means

  • that intuitive expertise is not going to develop in a chaotic universe or in a chaotic world.

  • So for example, I personally do not believe that that's stopped because people pick stocks

  • to invest in can develop intuition because simply the market takes care of it. There

  • isn't enough regularity in what's going to happen to prices for intuitions to develop.

  • We also know about political forecasters when they forecast long-term, they are really no

  • better than a dart-throwing monkey. And they are certainly not better than the average

  • reader of the New York Times. Intuitions and the reason it's not the pundit's fault. And

  • that research has been done with pundits and CIA analysts and regional experts. It is really

  • not their fault that they cannot predict the long range future 10 or 15 years. They are

  • quite good at short-term predictions. They are really not good at all in long-term predictions.

  • It's not their fault. It's the fault of the world. The world is probably not predictable.

  • And if the world is not predictable, then you are not going to predict it. When there

  • are marginal situations where there is some predictability but poor formulas do better

  • than individuals. That is the domain where formulas beat individuals regularly is a domain

  • of fairly low predictability. Because when there are weak cues, people are not very good

  • at picking them up and are not good at using them consistently. But formulas can be generated

  • on the basis of experience and they will do a better job than individual judgment. Okay.

  • Now, I've introduced you to System 1 and System 2 and I've told you something about skill

  • and about skill in System 1. Now I'd like to point out something that we sometimes have

  • intuitions and that applies to political forecasters and to stock pickers and to all of us. Quite

  • frequently we have intuitions that are false. And they come up and come to mind and they

  • are subjectively undistinguishable from expert intuitions. So I'm now talking of people who

  • have intuitions that are not based on expertise. And they come. They're System 1 in the sense

  • that they are effortless and automatic. And where do they come from? And that is what

  • I'm going to try to illuminate, shed some light on in the rest of the talk. So I want

  • to introduce you to System 1. And first of all, let me get one thing clear because I

  • might forget. I use System 1 and System 2 those terms and very shocking terms in my

  • discipline. You are really not supposed to do that. Because every psychologist gets told

  • fairly early you're not supposed to explain what happens in the mind by invoking little

  • agents inside the mind and explain what the mind does by what the little agents do. Those

  • are homunculi and that's a bad word in psychology. I'm going to use System 1 and System 2 absolutely

  • as homunculi. Now, what do I have to say in my defense? First of all, well, I'm warning

  • you. Those are fictitious characters. They don't exist. I don't believe there is such

  • a thing as System 1 and System 2. Don't look for them in the brain, because they are not

  • two systems in the brain of which one does one and the other does the other. So why am

  • I using this terrible language? I'm using it because I think it's helpful. It fits the

  • way our minds work and to explain the background of that decision of why I use System 1 and

  • System 2, I refer you to a very good book. It's very entertaining. It's by Joshua Foer

  • and it's called Moonwalking with Einstein. It came out earlier this year. And what the

  • book is about. Joshua Foer, he's a science writer. And he went to the Memory Championship

  • of the United States. You might not know there is such a thing but there is. So people memorize

  • decks of cards and very, very long lists of things and perform feats that we think are

  • completely extraordinary. Joshua Foer decided to find out what happens. And a year later

  • he was actually the champion -- the Memory Champion of the United States. And the book

  • is a story of how he did it. And basically the story which was known to the Greeks in

  • some form is that memory is very, very good at something and terrible at other things.

  • Memory is terrible at remembering lists. We're really not good at remembering lists. Memory

  • is superb at remembering routes through space. That evolution, evolution has endowed us with

  • an ability to remember routes and not lists. So now, you can trick yourself. If mentally

  • you have a list and you want to remember the list, then you create a mental route and you

  • distribute the items on your list along the route. And then, when you want to remember

  • the deck of cards or whatever it is, then you go through your route and you pick out

  • items one after the other, because that you can do. It turns out something very similar

  • happens in another context. People are very good thinking about agents. The mind is set

  • really beautifully to think about agent. Agents have traits. Agents have behaviors. We understand

  • agents. We form global impressions of their personalities. We are really not very good

  • at remembering sentences where the subject of the sentence is an abstract notion. But

  • an agent is very, very good. So just remember whenever I say System 1 does X what I mean

  • is x is a mental activity that can be performed without effort. You'll remember a lot more

  • about System 1 if you think about it as doing things than if you think of those mental activities.

  • It helps me think and I think it helps other people understand. Okay. So let me introduce

  • you to System 1. I begin with a study, just an extreme case of this study was done at

  • the University in the UK and like in many department of biology actually. And like many

  • places in the UK, they have a small room which is a tearoom, coffee room, where people can

  • make themselves tea or coffee and get some biscuits and there is an honesty box and they

  • pay into the honesty box. And somebody had the bright idea of sticking a poster right

  • on top of the honesty box and of changing the poster once a week. And so, this is week

  • one. And that's the poster. Week 2 is flowers. Week 3 is eyes. And so on. Now, what is remarkable

  • about this is, this is something that happens to people. They have no idea it's happening

  • to them. In fact, they have no idea about the posters. They are barely aware there are

  • posters there. They certainly don't know the posters change systemically. They have no

  • idea that the posters influence their behavior. System 1 can do those things. Those things

  • we, a lot is happening in our mind that we are not fully aware of. We are not aware of

  • at all in fact. And there is a link between eyes and being watched and being watched and

  • not wanting to do bad things or wanting to do good things. All of this is deep in our

  • associative memory and it gets activated. You see eyes especially those large eyes on

  • week 1 and it does something to you that you may not be aware it does. Now let me show

  • you something else. This, I just want to enumerate very briefly what happened to you in the first

  • couple of seconds when I put this on the screen. And first of all, you read them. You read

  • the words. Now, you didn't intend to read the words. You didn't have to decide. You

  • had to read them. You had no choice in the matter. Second, ideas and images and memories

  • came to mind probably none of them very pleasant. So that's the second thing. Another thing

  • that happened is physical. You recoiled. This is actually being measured. And when people

  • are exposed to threatening word, they move back. So the threat is to some extent to some

  • slight extent taken to be real. The symbolic threat is taken to be real. You made a disgust

  • face. You experienced disgust. And that is getting to be interesting because those things

  • are reciprocally reinforcing. So if you make a disgust face, you are more likely to feel

  • disgust. If you make a smiling face, you are more likely to think that things are funny.

  • So you know, one of my favorite experiments along those lines is, you take a pencil, you

  • stick it in your mouth like that. And cartoons will appear funnier to you. Because, when

  • you stick a pencil into your mouth like that, you're making a smile. And just the sheer

  • muscular change is enough to feedback into our emotions and our feelings. This is all

  • fairly important, because what it means is, you can think of well, let me add something.

  • Then I'll pull it together. I think of System 1 very largely in terms of what happens in

  • associative memory. To think of associative memory, you can think of a gigantic network

  • of ideas. And the ideas are linked to each other in various way, associatively, some

  • of them are causes of other things or categories, example, instances of. There are many different

  • links but you have a huge representation of what we have in mind. And at any one time

  • the stimulus occurs, it activates a subset of those notes in that representation of memory

  • and then activation spreads through the associative network; not a lot, but it spreads some. So

  • for example, you're now and we can know that it spreads, because we become sensitized to

  • other ideas that have been activated in this fashion. So for example, right now, if somebody

  • whispered words in your ears, you would be much more likely to detect and recognize words

  • like sickness and smell, instinct, and nausea, and hangover. A lot of the associations have

  • been activated. You're not aware of any of them. You're not aware of anything. Those

  • are not conscious activations. But they are activations nonetheless. And because those

  • ideas are partially activated, weak stimulus is going to be sufficient to bring them over

  • threshold. This again is a very important function of System 1 associative memory. We

  • are prepared basically by this spreading activation prepares things for what might come next.

  • You will be able to recognize and respond to things more easily than before. Then something

  • else happens. And this is there are two words here, banana vomit and you made a story. What

  • happens, you know, there is really no need to do that, but in effect, this was sufficient

  • to create a causal link so that somehow the bananas caused the vomit. You didn't make

  • a conscious decision for that to happen, but we know that's the kind of thing that happens.

  • As soon as a stimulus is presented, we look back for causes; the associative machinery

  • looks back and latches on possible causes. Here it's very simple to find a cause and

  • you know this has an effect. So temporarily, you know, you don't like bananas because an

  • association has been created. And that happens because of the causal surge. So [pause] this

  • should give you a sense of one of the functions of System 1. And to complete that, let me

  • show you something else. So this is a famous psychological demonstration. Many of you might

  • not have seen it. You read that as A B C. You read this as 12, 13, 14, but the B and

  • the 13 are physically identical. So this tells us something quite important about the way

  • that associative machinery in System 1 work on new stimuli. Everything is made coherent.

  • So, in the context of letters, that ambiguous stimulus is going to be read as a letter.

  • In the context of numbers, it is going to be read as a number. What is quite important,

  • two aspects here, one is the coherence and the other is that you are not aware of the

  • ambiguity. The ambiguity is suppressed. That is, you just get one interpretation. In this

  • case, it's a coherent interpretation. And that is the way that the system works. It

  • generates associatively coherent representations of reaction to situation. Associative memory

  • or System 1 is also very pository about world knowledge. So when an event occurs, our reaction

  • to it is informed by a lot of things that we know. And I'll give you my favorite example

  • of this. This is people are listening to sentences while events in their brain are recorded.

  • An upper class male British voice says, "I have a large tattoo, I have large tattoos

  • all down my back." And approximately 3/10th of a second later the brain responds with

  • a characteristically surprise. This is astonishing if you stop to think about it. There was that

  • voice. You have to classify it as an upper class British voice. Now upper class British

  • men don't have tattoos down their back, something is odd and you get a surprised reaction. You

  • get a mobilization of System 2 because System 2 is the one that pays attention. Surprise

  • calls attention. A male voice saying I believe I'm pregnant of course same thing. So this

  • system holds a world knowledge and uses a world knowledge to classify situations as

  • normal or abnormal and it does that at top speed. And it updates very quickly. Well,

  • I'll tell you a story about updating. It updates what it considers normal. Now, this is an

  • anecdote. You're free not to believe me. I believe it because it's a personal experience.

  • We were some years ago on vacation in Australia in resort all of 40 little villas and in the

  • evening we go to have dinner first evening and we meet a psychologist from Stanford.

  • Ah, surprise, coincidence and we are very delighted to meet each other. Now, two weeks

  • later, we're in the theater in London. And it goes dark. And we watch. And then, the

  • lights come back on and next to me, same guy. Now, the important point is that I was less

  • surprised the second time than the first. Because "Oh, John, he is the guy I meet everywhere."

  • [laughter] It takes very little time to create what we

  • call "a norm." So one event, the second event links back to the first. If I had met anybody

  • else, that is what's impressed me. If I had met anybody else, I would have been more surprised.

  • And that's odd if you think about statistically, it's crazy. But in fact, it was very clear

  • that and I wouldn't say that I consciously expect to see John wherever I go. But, you

  • know, if I'm going to meet someone, I'd be prepared to meet John.

  • [laughter] Now, I've mentioned something about causal

  • thinking. And I want to give you some sense how that works. So it's a question, which

  • is more probable that a mother has blue eyes if her daughter has blue eyes or her daughter

  • has blue eyes if her mother has blue eyes? Now again, as in the bat and ball, there is

  • an intuitive response and the intuitive response is that it's more probable that a daughter

  • has blue eyes if her mother has blue eyes than the other way around. If you stop to

  • do the math on the assumption that the incidence of blue eyes is the same two generations the

  • probabilities are strictly equal but even before you do the math, your reasoning flows

  • along causal lines. Your thinking flows along causal lines. This happens intuitively. One

  • of these feels okay. It feels more coherent and the coherence that we experience can be

  • turned into a judgment of probability. That is, the confidence that we experience is a

  • judgment of probability. Now, I'm going to skip the other example. And I said earlier

  • that people have intuitions that are not necessarily true. And that people are confident in judgments

  • that are not necessarily true. And I would like to sort of present a tentative theory

  • about how that happened. And the general idea is very straightforward. When we're asked

  • a question that we cannot answer, typically System 1 is going to come up with the answer

  • to a related question that is easier. And it's going to use that answer to the wrong

  • question, the question that hasn't been asked in place of the question that was asked. We

  • call that a mechanism of substitution: substituting an easier question for a hard one. It happens

  • automatically. People are not aware that it happens and it is a source of many intuitions

  • that don't come from expertise and they are much less likely to be correct than the intuitions

  • that do come from expertise but they come with equal confidence just about. So there

  • are several mechanisms that take part in this substitution thing and I'd like to introduce

  • them. One of them which I call the mental shotgun is that when you are instructed to

  • perform an operation, you typically perform other operations as well that are related

  • to it associatively, are related to the target operation, but they are different. My favorite

  • example is, I'll say words and you are to judge as quickly as possible whether the words

  • rhyme or not. And the first pair of words is vote note. That's easy. The second pair

  • of questions is vote goat. And vote goat is substantially harder than vote no. Why? Although

  • nobody else asked you to, you spelled. And vote goat, there is a mismatch in spelling.

  • Although they rhyme at least as I pronounce them just as well as vote note, you have a

  • conflict and the conflict slows you down. So typically, we compute more than we intend

  • to compute. And we can and that allows for substitutions to take place. So let me give

  • you an example of the substitution here. The question here would be, "Which of the three

  • figures is larger on the screen?" And the answer is, "they're equal." All three figures

  • on the screen are of equal size. But it's a very powerful illusion. We see the figure

  • on the right as larger than the figure out left. And we see it because we can't help

  • it. Although you were told to think of it as a two-dimensional object, you compute the

  • three-dimensional solution in which the object on the right is in fact larger than the object

  • on the left and that is what you see. There are many other examples of this general process.

  • Another one I like is called the dating heuristic. Students are asked in a survey they're asked

  • a couple of questions. How happy are you and the other is how many dates did you have last

  • month? And if you ask the questions in that order, the correlation is essentially zero.

  • Turns out there are many things in life that determine happiness and dating is not particularly

  • important. You invert the order. So you ask people, "How many dates did you have last

  • month and how happy are you with your life as a whole?" Correlation is .66.

  • [laughter] What has happened and this is both a heuristic

  • and example what I call a focus and an illusion. That you have an emotional reaction to the

  • student has an emotional reaction to the question about the number of dates. That emotional

  • reaction is sitting there. Then you're asked the related question about happiness and without

  • knowing that you are doing this, you substitute one for the other. And you can do it for many

  • questions. Now, it's not that people are confused what happiness is. They know happiness is

  • not satisfaction with the number of dates. It's just that this is the answer that comes

  • to mind to the happiness question. There has been substitution and you are not aware of

  • it. Now, there is a process that is essential to this and this is another strange ability

  • of System 1. We can map intensities across different dimensions. So I'll give you my

  • standard example for this. It's about Julie who is a graduating senior and she read fluently

  • when she was age 4 and the question is what is her GPA? And the odd thing is that you

  • know what her GPA is pretty much. At least you have an idea. I mean, it's clearly about

  • 3.2. It's clearly less than 4 about 3.7 maybe which is ridiculous of course. But how do

  • people get to 3.7 or somewhere like that? Well, here is how it goes. She read fluently

  • at age 4. That gives us an impression of precocity. How precocious was she as a reader? And that

  • people could express that in percentiles. What is the likelihood that you could meet

  • a child who would read faster than that? Then when you are asked a question about what is

  • her GPA? Without your knowing it, you are matching the percentiles and you get the GPA

  • that is about as extreme in the distribution of GPA as reading at age 4 is in the distribution

  • of reading age. Completely unaware. Statistically, completely absurd. You should be much more

  • regressive. This is not the correct answer. But this is a compelling subjective answer.

  • This is one of the mechanisms that leads to intuitive errors this mechanism of substitution.

  • And I'll give you one more example. International travels, this is an experiment. The experiment

  • was run during a period when there were many terrorist incidents in Europe. So that's a

  • background. How much will you pay for insurance that pays 100,000 dollars in case of death

  • for any reason? And how much would you pay for insurance that pays 100,000 dollars in

  • case of a death in a terror incident? People pay much more for the second than for the

  • first. [laughter]

  • And the reason that they do is that there is an immediate response which is how afraid

  • am I? And I am more afraid, most people are, I'm more afraid of the idea of dying in a

  • terrorist incident than they are afraid of dying. And that is the mapping that takes

  • place. Again, you know, it's that's the way it works. This is the associative machinery.

  • And when beautiful thing about it it doesn't get stumped. It produces an answer to questions

  • that it doesn't know how to answer. But it produces them by answering easier questions

  • and a lot of our mental life is conducted in just this way. So let me complete the circle

  • and talk a little bit about subjective confidence. Subjective confidence, which is closely related

  • to the probability of being correct, is actually not a judgment at all. It is a feeling. It

  • is a feeling that people have. And I think we know where the origin of that feeling is.

  • And it is System 1 if you will assessing the fluency of its own processing; assessing the

  • coherence of the story it has created to deal with the current situation. And if the story

  • is coherent, confidence is high. Now, this is disastrous in some ways, because you can

  • make a very coherent story out of very little information and out of information that is

  • in fact not reliable. The quality of the story depends very little on the quality and quantity

  • of the information so people can be very confident with very little reason. Confidence is therefore

  • not a good diagnostic for when you can trust either yourself or somebody else. And if you

  • are to evaluate whether you can trust somebody who has a lot of confidence, that's not the

  • way to do it. The way to do it as I'm saying earlier is to ask what environment have they

  • been in? And have they had an opportunity to learn its regularities? Subjective confidence

  • is not a good indicator. So that's, you know, the story I could tell in about 45 minutes

  • about the two systems. So let me remind you they don't exist. But I think you should feel

  • free to think in those terms, because what you may be beginning to do is, you may be

  • beginning to have an idea of the personality of System 1 and System 2. Now this is ridiculous,

  • but having an idea of those personalities will actually enable you to think better about

  • psychological events than if you were just had a long list of unrelated phenomena. So

  • those ideas, those personalities, have a certain coherence. And, you know, they're worth something

  • in the coin of being able to make judgments. Okay. I think we should open for questions.

  • So.

  • [Applause].

  • >> John: We have the mic up there and I also have hand-held mics if somebody has questions.

  • Somebody's got to ask the first question.

  • >> Male # 1: Hey. How fixed or plastic are the System 1 processes? And are there thing

  • like mindfulness or emotional regulation that have any effect?

  • >>Kahneman: As I have described it, System 1 can be updated in terms of content very

  • regularly. So you can learn in one trial what is normal and what is not normal. What is

  • very difficult to do is to get control over how it works, over the rules of its operation.

  • And so, I do not know of a lot of evidence that people, that System 1 can change unless

  • you have a quiet skill which requires reinforced practice. What you can do and what people

  • clearly can do is you can educate your System 2. And you can educate and you can learn to

  • recognize situations in which System 2 takes over and takes control of the reaction thereby

  • avoid some mistakes. Can't be done too much. But if I don't sound optimistic about training

  • System 1, it's because I'm not.

  • >> Male #2: Another question about training System 1. You talked about reinforcement learning

  • and the time constants and the immediacy in building expertise, but many of the practices

  • we have around building software development, the time constants are somewhat longer and

  • in particular you gave a counterexample which was your Australia/UK visit and the fact that

  • a single incident with John predisposed you to that association. And so, I wonder if there

  • has there been any testing to see what time constants really play a role here?

  • >> Kahneman: No. In terms of updating and learning associations, this is something we

  • can learn quite quickly. You can be taught to be afraid of something without anything

  • else happening. And so, in that sense, System 1 associative memory can be updated. And you

  • can now be developing software expertise that is a somewhat different story and it's more

  • like learning how to be a chess master. And that takes a lot of experience. So that you

  • and a lot of reinforcement and it had better be effective reinforcement. Now, in the software

  • thing, the time is to some extent not a big problem. Because ultimately you are going

  • to see it all together: the error you made and the correct solutions. So time is not

  • major factor. In learning, you know, how to not steer a tanker, that's reinforcement is

  • very slow. And it's a lot harder to learn to do that than it is to learn to steer a

  • smaller ship.

  • >> Male #3: So this is a pretty broad question so please take this whichever direction you

  • like. But I was just wondering how these systems come into play and how you see it in media

  • and advertising and maybe I was thinking of how it's changed over time.

  • >> Kahneman: Well, it's very clear that advertising is here to address System 1. It doesn't convey

  • information for judgments. It moves your emotions and it creates associations. That's what it

  • is intended to do and it's pretty effective. So, a lot of politics is addressed to System

  • 1, a lot of political messaging. The influences of System 1 activities and you know which

  • are really important and we should be thinking about. It's pretty frightening. One of my

  • colleagues at Princeton, my younger colleagues at Princeton, has done studies on the effects

  • of facial characteristics on political preferences. And it's utterly amazing. You take 538 pairs

  • of pictures of the two contestants for each Congressional race and you show those pairs

  • of pictures to Princeton students for 1/10th of a second and you ask, "Which looks more

  • competent?" That predicts 70% of elections. So the impact of System 1 on the decisions

  • we make for example, how much to pay in an honesty box, that is something that we're

  • really very rarely aware of and it's much more than we think.

  • >> Male #4: So in, although that you say System 1 and System 2 don't show up as specific structures,

  • have there been functional MRI, diffusion-spectral imaging, diffusion-tensoral imaging studies

  • that highlight whether System 1 is more primal brain initial activation and System 2 is more

  • neocortex?

  • >>Kahneman: Well, you know, System 1 is extremely sophisticated. So it's not, that is in part

  • why I don't believe there is any simple representation in the brain of those two systems because

  • what I've called System 1 operation by their characteristics include both innate responses

  • and highly skilled responses. And the whole the representation of world knowledge is in

  • System 1. So it's hard to classify one as primitive. And I should add that System 2,

  • the reasoning system as it were is not necessarily rational. I mean, System 2 knows what it knows.

  • It knows what we know and we don't know a lot. So it's not that System 2 is infallible

  • and that all the mistakes come from System 1. We make very significant mistakes when

  • we think very seriously. Yes.

  • >> Male #3: So you mention that experts when making long-term forecasts and they trust

  • their intuition they're often wrong. But there are still a lot of people who listen to them.

  • So, is it bad for the society in general that we listen to experts who may be just as wrong

  • as we are and should we be worried? Should we try to do something?

  • >>Kahneman: I think there is a very good reason for the demand for experts. I was referring

  • to a particular book that you may want to read or you may want to look for the New Yorker

  • review of that book. It's a book by Phil Tetlock on political judgment where he studied forecasts

  • in the time range of 10, 15 years of political forecasts. And one of the interesting observations

  • is who are the people we like to listen to as pundits? And there are people with very

  • high confidence who think they understand the world. Now, they actually are worse than

  • chance. I mean, they are worse than people who are more hesitant. But we want them. We

  • need them. And so, there is a real demand for overconfidence. [laughter]

  • >> Male #5: So as you were going through all the slides of the various illusions, by the

  • time you came to the three figures on the screen, I guess I was expecting there was

  • something. So even though the lot on the right looked bigger, I looked again okay and they're

  • the same. So was that System 1 or System 2.

  • >> Kahneman: That is clearly System 2. And that is the way we can learn to overcome illusions

  • both visual and cognitive. You still see it as one larger than the other, but you know

  • that when you see a display like that, you shouldn't trust your eyes. And to a similar

  • extent you can recognize that you're in a situation where somebody is having too much

  • effect on you because she's very eloquent. But you know the content may not be there.

  • And so, you force yourself to be skeptical.

  • >>Male #5: Is there any research to that effect that people would avail that advertising is

  • going to have an emotional effect on them? Is there any res- let me say that I'm aware

  • that advertising is supposed to have an emotional effect on me activate System 1, will I be

  • better suited to sort of ignore those things?

  • >>Kahneman: I mean you certainly are going to ignore it better than if you didn't know

  • it whether you're capable of ignoring it altogether, that I'm much more skeptical about. The real

  • thing is not to expose yourself to it. Because once you're exposed to it, it's going to affect

  • you. And you know, those effects are the cues in our world that we are not aware of can

  • be extremely powerful. There is a whole line of study, it's not exactly to your point,

  • but I must tell you that story. There is a whole line of studies on what happens to people

  • when they're exposed to the idea of money. And for example, they perform one task and

  • there is a computer nearby and on the computer there is a screensaver and the screensaver

  • are dollars floating in water. Dollar bills floating in water. That makes you selfish.

  • It makes you reluctant to ask for the help of others. It makes you put your chair further

  • away from the chairs of other people when you have to set up an interview situation.

  • It has effects on all sorts of behaviors that people are completely unaware of. And the

  • links are symbolic. And you can be aware of that. How can you resist it? We are exposed

  • to money and it's going to have some effect. Now, if you're designing an organization or

  • if you're designing an environment for people, you can create an environment that will remind

  • people of money all the time or you can create an environment that will remind them of other

  • things and that will control their behavior to some extent.

  • >> Male #2: Although possibly not one of the big five in the personality trait categories

  • yet, have you developed any empirical testing that ranks people on a scale of one-to-two

  • and shows where they fall in terms of default behaviors.

  • >> Kahneman: Well, there is a relevant scale on the activity of System 2. And the bat and

  • ball question is actually a very, very good question. There are several examples of this.

  • My former colleague Shane Frederick developed that test. It's called the Cognitive Reflection

  • Test and the people who fail that item that is, who say ten cents they are different in

  • some interesting ways from the people who are better able to make it. And let me give

  • you an example. You ask them, you know, standard Amazon questions. So you ordered a gift for

  • yourself. How much will you pay extra to have it tomorrow rather than the second business

  • day? And the people who fail this item are willing to pay more to get it tomorrow. So

  • there are connections. What there isn't and I'm very surprised there isn't, I don't know

  • there should be tests of intelligence that are tests of System 1. That are tests of the

  • richness and subtlety of the model of the world that we have. All the intelligence tests

  • that we have are tests for System 2. They're reasoning tests. We don't have and I wish

  • somebody would develop it and I hope somebody will but, in fact, we don't have it.

  • >>Male #6: Hi. So this is sort of a 2-part question. So do you find that people who are

  • more System 1 or System 2 prone for immediate judgments are more likely to be that way long-term

  • like larger decisions?

  • >>Kahneman: I don't know enough about this.

  • >>Male #6: Yeah.

  • >>Kahneman: We do know that self-control and the general activation of System 2 is an important

  • personality characteristic. And you know its presence in a rudimentary form at age four

  • and has implications. The ability the test is called The Marshmallow Test. You ask a

  • child you can have one marshmallow now or you can have two if you wait 15 minutes. That

  • predicts what they will do 20 years later remarkably well so there are things that are

  • quite stable.

  • >> Male #6: And the other part is that have you encountered people who would say they

  • have to make a decision and they're aware that their System 1 mind is telling them decision

  • A their System 2 mind is telling them decision B. What do people go with?

  • >>Kahneman: I don't know enough.

  • >>Male #6: No?

  • >>Kahneman: No, I don't know enough. [pause] No, I don't know enough. It would be so dependent

  • on circumstance whether you impose the System 2 judgment. In many cases, really System 2

  • just endorses what System 1 subjects to. That's the model you have. Sometimes you can overturn

  • it. It's hard work.

  • [pause]

  • Thank you.

  • [Applause]

>> John Boyd: All right. I'm John Boyd. It is my great pleasure to introduce Professor

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B1 中級

@谷歌介紹:丹尼爾-卡尼曼 (@Google Presents: Daniel Kahneman)

  • 181 26
    Penny 發佈於 2021 年 01 月 14 日
影片單字