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>> John Boyd: All right. I'm John Boyd. It is my great pleasure to introduce Professor
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Kahneman today. And I just want to give you a brief background on his outstanding career.
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He started in 1954 received his bachelors in experimental psychology and mathematics
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from the Hebrew University in Jerusalem. In 1961, he was awarded his Ph.D. from University
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of California Berkeley right across the bay in Experimental Psychology. In 1979, he and
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his coauthor Amos Tversky published their seminal paper on Prospect Theory which started
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to change the way people reframed the argument around gains, losses, and decision-making
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under uncertainty. Several years later in 2002, Professor Kahneman was awarded the Nobel
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Prize largely on the work of Prospect Theory of. And Nobel Prize isn't always impressive;
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his perhaps more so because there isn't a Nobel Prize in psychology. He had to win his
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Nobel Prize in economics. And as far as I know, there's only one other person, one other
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psychologist, who's won a Nobel Prize and that's Ivan Pavlov. He may be a physiologist,
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we could argue about that. Years later, in 2007, Psychologist tried to reclaim Professor
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Kahneman as one of their own when the American Psychological Association awarded him Lifetime
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Distinguished Contribution Award. And today he is a Senior Scholar at the Woodrow Wilson
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School of Public and International Affairs at Princeton University and he's here to talk
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about his new book Thinking Fast and Slow. Now Google's mission which we all know is
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to take the world's information and to make it more useful and universally accessible.
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And all information, all knowledge, is important, but I think some again is more important than
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others. Because the information that he'll present today I think it's very personal;
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it's about each of us. And, if you'll listen carefully it's going to change the way you
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think about yourself and the world around you. So please join me in welcoming Professor
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Kahneman to Google.
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[Applause]
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>> Kahneman: Thank you. Well, I think intuition has been discussed a lot in recent years and
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I'll be talking about intuition. There are two camps in this discussion naturally there
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is the pro and the con. And of course, many people here will have read Malcolm Gladwell
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Blink which although it's not unconditional defense of intuition, it certainly gave people
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the impression that sometimes we magically know things without knowing why we know them.
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Within the discipline of psychology and the decision making there is a group and it is
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headed by a very interesting figure called Gary Kline who wrote a book that I recommend.
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Its Sources of Power is one of his books that I would recommend the most warmly. And they
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are great believers in expert intuition. The other side there are skeptics about intuition
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in general and including expert intuition. And I have long been counted as one of the
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skeptics because my early work with Amos Tversky was about intuitive errors and flaws and biases
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of intuitive thinking. Today you find that discussion in many places and for example
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in medicine among the popular writers; two writers both of whom write for the New Yorker,
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Jerome Groopman and Atul Gawande. They clearly differ. Atul Gawande is in favor of formal
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systems, very skeptical about human judgment and wanting to prove all the time and Jerome
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Groopman being in fact, although he doesn't quite admit he really likes good old fashioned
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medical intuition. Of course he likes physicians well-educated. But he doesn't like formal
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system and the issue in medicine is "What are the role of evidence based medicine and
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how do you allocate that with the function of intuition?" The background actually, part of the background for what
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I'll talk about today is a strange collaboration in which I engaged with about eight years
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with Gary Klein, whom I mentioned. He is a guru of a group of people who really, I wouldn't
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say they despise what I do but they certainly don't like what I do because they think that
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the emphasis and biases of judgment has drawn an unjustly unfavorable picture of the human
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mind. And by and large I am inclined to agree. Seven or eight years ago I invited him and
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we worked together for a number of years trying to figure out where is the boundary? Where
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is intuition marvelous and where is it flawed? And I think we can tell. And we wrote a paper
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at the end of six or seven years with a lot of vicissitudes that we went through since
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we basically don't agree. We wrote a paper the title of which was A Failure to Disagree,
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because on the substance I think we know and we both agree where you can trust intuition
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and where you cannot. Emotionally we haven't changed. He still hates the biases and doesn't
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think that errors of experts are very funny and I think that errors of experts are quite
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funny [laughter] so that's a difference right there. There are two modes of thinking that
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all of us are familiar with. And there is one mode, one way for thoughts that come to
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mind and listen to this. You know about this lady that she's I think adjust as quickly
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as you know her hair is dark. And it's interesting to dwell a bit about this. It is this is not
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something that the judgment that she is angry, the impression that she is angry. Doesn't
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feel like something you did. It feels like something that happens. It happens to me.
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We have the basic experience is a passive experience in those judgments. And that is
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true of perception, when we see the world we don't decide to see it. It is true of impression.
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And it is true in general what we call intuitive thinking. It just happens. It comes from somewhere.
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And we are not the author of it. Now, there is another way that thoughts come to mind
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and here I suppose essentially nothing came to your mind, but the answer is 408. To produce
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the 408, requires a completely different kind of operation. You have to retrieve the program
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that you learned in school. The program consists of steps. You have to go through the steps.
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You've got to pay attention successively to partial products and so on. And keep things
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in mind and keep the whole program in mind. This is how it works. This is something that
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you do. It is not something that happens to you. And there are many indications that this
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is how it works. One is that Physiology indicates and this is how it works: pupil dilates. This
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is something that I studies many, many years ago that people really on a program like that
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if you're on a problem like that if you're going to do it in your head, your pupil will
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dilate. The area will increase by about 50% as soon as you engage in that. And it will
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stay dilated as long as you're working and it will sort of collapse back to normal size
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either when you quit or when you find the answer. So this is another way thoughts come
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to mind. And this is definitely not the intuitive way. Here we are we feel a sense of urgency.
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We feel something deliberate is happening and a very important aspect of it this is
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effortful and what psychologists mean by effort is basically, if you want the quick introduction
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to what effort is, this is something you cannot do while making a left turn into traffic.
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You cannot do it and you shouldn't try. And the reason is that there is limited capacity
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to exert effort. And if you are engaged that capacity or those resources at one task less
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is available for another task. Now, there is another function of System 2. And here
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I'm going to tell you a riddle. Most of you are familiar with it. A bat and a ball together
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costs 1.10. The bat costs more than the ball. Of course how much does the ball cost? How
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many people know this riddle by the way? Oh, okay. So it's still usable. The point about
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this riddle is that the number came to your mind. And the number is ten cents. And everybody
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just, I think. Maybe here they're exception, very few exceptions. People confess that the
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number ten cents immediately came to mind. Now, it's wrong. Ten cents and dollar 10 is
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a dollar 20. The solution is five cents. What is interesting here is that at Princeton,
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at MIT at Harvard and I don't know about Stanford or CalTech about 50% of students asked this
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question of undergraduates say ten cents. And we learn something very interesting when
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somebody says ten cents. We learn that they didn't check because if they had checked,
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they wouldn't say ten cents. So, there is a sense of confidence that people have that
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these people in particular have and it brings us to another function of what I'll call System
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2. System 1 is the intuitive one; they perform those automatic and activities and System
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2 is the effortful one the one that the deliberate one. And the reason that I classify this as
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System 2 operation is that self-control and controlling your attention and deliberate
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exertion of effort are impaired when by other activities. So, if for example, a trivial
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example, if somebody is asked to retain seven digits in their head and you then give them
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a choice between chocolate cake, sinful chocolate cake and virtuous fruit salad they're more
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likely to choose the chocolate cake than they would if they didn't have seven digits in
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their head. It takes effort to control your impulses even such mild impulses as a preference
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for chocolate cake. So you should be aware of that difference between System 1 operations, the automatic ones and
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System 2 operations, the deliberate ones, it comes very clearly when in driving. So
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driving is a skill. And any skilled activity measure of skill is that things begin to happen
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automatically. So you can drive and conduct a conversation. You cannot make a left turn
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into traffic, but by and large, we can drive and talk. So driving is largely automatic.
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Braking, when there is any sign of danger, braking is completely automatic. That is,
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you can notice while you're braking, but you first respond so that the response is immediate,
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it is fully automatic. Now, in some places, not here where people drive in snow or ice,
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they learn about skids. And then, occasionally, you'll find yourself as a driver in a skid.
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And then System 2 will be mobilized because in a skid you're not supposed to do anything
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that comes naturally to you. You shouldn't brake and you shouldn't steer away from the
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skid. You should leave the brakes alone and steer into the skid, completely non-intuitive.
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Now, when people have a lot of practice with skids that too becomes automatic. So one thing
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that we can tell about System 1 and System 2 those two types of operations, is some of
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the basic innate operations, functions that we have such as having emotional reactions
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to things, all this is System 1. We don't choose to do it. It just happens to us. But
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also System 1 is where skill is. That is when we get to be skilled at something it becomes
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automatic and it demands your resources and we get to be very good at it. Now, the issue
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of intuition and here I'm not sure, but I suspect that Malcolm Gladwell really did us
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a disservice by giving us a sense there is magic to intuition. There really is no magic
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at all and we should understand how it works. Intuition and Herbert Simon who was Psychologist
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then and economist and a political scientist Nobel Laureate, Herbert Simon gave a very
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good definition about what intuition is. It is simply recognition. There is really no
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difference between the physician recognizing a disease, you know, a particular disease
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from a facial expression or something and a little child learning, pointing to something
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and saying doggie. The little child has no idea what the clues are but he just said.
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He just knows this is dog without knowing why he knows. And once you think about it
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this way, this really demystifies intuition to a very considerable extent. And it also
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leads you to sort of a solution to the problem Gary Klein and I were trying to solve. When
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can you trust intuition and when can't you? And then it becomes an issue of is the world
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regular enough so that you can learn to recognize things? Or and then did that particular individual
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have an opportunity to learn the regularities of the world? And so, the world of chess players
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is highly regular. And statistically, the world of poker players is very regular. So
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there is an element of chance, but there are rules and the mind is so set that if there
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are rules in the environment and we're exposed to them for a long time, and we get immediate
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feedback on what is right and wrong, or fairly immediate feedback, we would acquire those
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rules. So all of us have expert intuition even if we are not physicians and we're not
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master chess players. I recognize my wife's mood from one word on the telephone. You know,
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most of you can do that. There's people that you know very well. All of us recognize dangerous
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driver on the next lane. And you know we get cues and we don't necessarily know what is
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the cue but this person is driving erratically and could do something dangerous. And this
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is a lot of reinforced practice and we're very good at that. We can learn about those,
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there are differences. Among experts, among professionals, in the level of expertise that
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they have and they depend in the level of intuitive expertise that they can develop.
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So for example, compare anesthesiologists to radiologists. Anesthesiologists get very
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good feedback, an immediate feedback whenever they do anything wrong. You know they have
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those measurements in real time. Radiologists get really miserable feedback about whether
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they're right or wrong. So you could expect an anesthesiologist to develop intuition much
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more than you would expect radiologist to develop intuition. And so, that is part of
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the answer about intuitive expertise. We don't need to disagree about that because we know
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pretty much when intuitive expertise is likely to develop. And as I said, we also that means
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that intuitive expertise is not going to develop in a chaotic universe or in a chaotic world.
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So for example, I personally do not believe that that's stopped because people pick stocks
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to invest in can develop intuition because simply the market takes care of it. There
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isn't enough regularity in what's going to happen to prices for intuitions to develop.
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We also know about political forecasters when they forecast long-term, they are really no
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better than a dart-throwing monkey. And they are certainly not better than the average
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reader of the New York Times. Intuitions and the reason it's not the pundit's fault. And
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that research has been done with pundits and CIA analysts and regional experts. It is really
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not their fault that they cannot predict the long range future 10 or 15 years. They are
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quite good at short-term predictions. They are really not good at all in long-term predictions.
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It's not their fault. It's the fault of the world. The world is probably not predictable.
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And if the world is not predictable, then you are not going to predict it. When there
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are marginal situations where there is some predictability but poor formulas do better
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than individuals. That is the domain where formulas beat individuals regularly is a domain
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of fairly low predictability. Because when there are weak cues, people are not very good
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at picking them up and are not good at using them consistently. But formulas can be generated
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on the basis of experience and they will do a better job than individual judgment. Okay.
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Now, I've introduced you to System 1 and System 2 and I've told you something about skill
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and about skill in System 1. Now I'd like to point out something that we sometimes have
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intuitions and that applies to political forecasters and to stock pickers and to all of us. Quite
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frequently we have intuitions that are false. And they come up and come to mind and they
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are subjectively undistinguishable from expert intuitions. So I'm now talking of people who
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have intuitions that are not based on expertise. And they come. They're System 1 in the sense
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that they are effortless and automatic. And where do they come from? And that is what
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I'm going to try to illuminate, shed some light on in the rest of the talk. So I want
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to introduce you to System 1. And first of all, let me get one thing clear because I
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might forget. I use System 1 and System 2 those terms and very shocking terms in my
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discipline. You are really not supposed to do that. Because every psychologist gets told
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fairly early you're not supposed to explain what happens in the mind by invoking little
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agents inside the mind and explain what the mind does by what the little agents do. Those
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are homunculi and that's a bad word in psychology. I'm going to use System 1 and System 2 absolutely
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as homunculi. Now, what do I have to say in my defense? First of all, well, I'm warning
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you. Those are fictitious characters. They don't exist. I don't believe there is such
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a thing as System 1 and System 2. Don't look for them in the brain, because they are not
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two systems in the brain of which one does one and the other does the other. So why am
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I using this terrible language? I'm using it because I think it's helpful. It fits the
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way our minds work and to explain the background of that decision of why I use System 1 and
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System 2, I refer you to a very good book. It's very entertaining. It's by Joshua Foer
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and it's called Moonwalking with Einstein. It came out earlier this year. And what the
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book is about. Joshua Foer, he's a science writer. And he went to the Memory Championship
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of the United States. You might not know there is such a thing but there is. So people memorize
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decks of cards and very, very long lists of things and perform feats that we think are
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completely extraordinary. Joshua Foer decided to find out what happens. And a year later
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he was actually the champion -- the Memory Champion of the United States. And the book
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is a story of how he did it. And basically the story which was known to the Greeks in
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some form is that memory is very, very good at something and terrible at other things.
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Memory is terrible at remembering lists. We're really not good at remembering lists. Memory
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is superb at remembering routes through space. That evolution, evolution has endowed us with
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an ability to remember routes and not lists. So now, you can trick yourself. If mentally
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you have a list and you want to remember the list, then you create a mental route and you
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distribute the items on your list along the route. And then, when you want to remember
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the deck of cards or whatever it is, then you go through your route and you pick out
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items one after the other, because that you can do. It turns out something very similar
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happens in another context. People are very good thinking about agents. The mind is set
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really beautifully to think about agent. Agents have traits. Agents have behaviors. We understand
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agents. We form global impressions of their personalities. We are really not very good
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at remembering sentences where the subject of the sentence is an abstract notion. But
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an agent is very, very good. So just remember whenever I say System 1 does X what I mean
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is x is a mental activity that can be performed without effort. You'll remember a lot more
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about System 1 if you think about it as doing things than if you think of those mental activities.
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It helps me think and I think it helps other people understand.