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  • I'm going to talk to you about optimism -- or more precisely

  • the optimism bias. It's a cognitive illusion that we've been studying in my lab for the past few years

  • and 80 percent of us have it.

  • It's our tendency to overestimate our likelihood of experiencing good events in our lives

  • and underestimate our likelihood of experiencing bad events

  • So we underestimate our likelihood of suffering from cancer, being in a car accident

  • We overestimate our longevity, our career prospects.

  • In short, we're more optimistic than realistic, but we are oblivious to the fact.

  • Take marriage for example. In the Western world, divorce rates are about 40 percent.

  • That means that out of five married couples, two will end up splitting their assets

  • But when you ask newlyweds about their own likelihood of divorce, they estimate it at zero percent

  • And even divorce lawyers, who should really know better

  • hugely underestimate their own likelihood of divorce.

  • So it turns out that optimists are not less likely to divorce

  • but they are more likely to remarry.

  • In the words of Samuel Johnson, "Remarriage is the triumph of hope over experience."

  • So if we're married, we're more likely to have kids.

  • And we all think our kids will be especially talented.

  • This, by the way, is my two-year-old nephew, Guy

  • And I just want to make it absolutely clear that he's a really bad example of the optimism bias

  • because he is in fact uniquely talented.

  • And I'm not alone. Out of four British people,

  • three said that they were optimistic about the future of their own families. That's 75 percent.

  • But only 30 percent said that they thought families in general are doing better than a few generations ago.

  • And this is a really important point, because we're optimistic about ourselves

  • we're optimistic about our kids, we're optimistic about our families

  • but we're not so optimistic about the guy sitting next to us,

  • and we're somewhat pessimistic about the fate of our fellow citizens and the fate of our country

  • But private optimism about our own personal future remains persistent.

  • And it doesn't mean that we think things will magically turn out okay

  • but rather that we have the unique ability to make it so.

  • Now I'm a scientist, I do experiments. So to show you what I mean

  • I'm going to do an experiment here with you. Okay.

  • So I'm going to give you a list of abilities and characteristics,

  • and I want you to think for each of these abilities where you stand relative to the rest of the population.

  • The first one is getting along well with others. Who here believes they're at the bottom 25 percent?

  • Okay, that's about 10 people out of 1,500. Who believes they're at the top 25 percent?

  • That's most of us here. Okay, now do the same for your driving ability.

  • How interesting are you? How attractive are you?

  • How honest are you? And finally, how modest are you?

  • So most of us put ourselves above average on most of these abilities.

  • Now this is statistically impossible. We can't all be better than everyone else.

  • But if we believe we're better than the other guy,

  • well that means that we're more likely to get that promotion, to remain married,

  • because we're more social, more interesting.

  • And it's a global phenomenon. The optimism bias has been observed in many different countries

  • in Western cultures, in non-Western cultures

  • in females and males, in kids, in the elderly. It's quite widespread.

  • But the question is, is it good for us? So some people say no

  • Some people say the secret to happiness is low expectations

  • I think the logic goes something like this: If we don't expect greatness,

  • if we don't expect to find love and be healthy and successful,

  • well we're not going to be disappointed when these things don't happen.

  • And if we're not disappointed when good things don't happen, and we're pleasantly surprised when they do, we will be happy.

  • So it's a very good theory, but it turns out to be wrong for three reasons

  • Number one: Whatever happens, whether you succeed or you fail, people with high expectations always feel better.

  • Because how we feel when we get dumped or win employee of the month depends on how we interpret that event.

  • The psychologists Margaret Marshall and John Brown studied students with high and low expectations.

  • And they found that when people with high expectations succeed, they attribute that success to their own traits.

  • I'm a genius, therefore I got an A, therefore I'll get an A again and again in the future

  • When they failed, it wasn't because they were dumb, but because the exam just happened to be unfair.

  • Next time they will do better. People with low expectations do the opposite.

  • So when they failed it was because they were dumb

  • and when they succeeded it was because the exam just happened to be really easy. Next time reality would catch up with them. So they felt worse.

  • Number two: Regardless of the outcome, the pure act of anticipation makes us happy.

  • The behavioral economist George Lowenstein asked students in his university to imagine getting a passionate kiss from a celebrity

  • any celebrity.

  • Then he said, "How much are you willing to pay to get a kiss from a celebrity if the kiss was delivered immediately

  • in three hours, in 24 hours, in three days, in one year, in 10 years?

  • He found that the students were willing to pay the most not to get a kiss immediately, but to get a kiss in three days

  • they were willing to pay extra in order to wait

  • Now they weren't willing to wait a year or 10 years; no one wants an aging celebrity

  • But three days seemed to be the optimum amount.

  • So why is that? Well if you get the kiss now, it's over and done with

  • But if you get the kiss in three days, well that's three days of jittery anticipation, the thrill of the wait.

  • The students wanted that time to imagine where is it going to happen, how is it going to happen.

  • Anticipation made them happy.

  • This is, by the way, why people prefer Friday to Sunday

  • It's a really curious fact, because Friday is a day of work and Sunday is a day of pleasure,

  • so you'd assume that people will prefer Sunday, but they don't.

  • It's not because they really, really like being in the office and they can't stand strolling in the park or having a lazy brunch.

  • We know that, because when you ask people about their ultimate favorite day of the week,

  • surprise, surprise, Saturday comes in at first, then Friday, then Sunday. People prefer Friday because Friday brings with it the anticipation of the weekend ahead

  • all the plans that you have. On Sunday, the only thing you can look forward to is the work week.

  • So optimists are people who expect more kisses in their future, more strolls in the park.

  • And that anticipation enhances their wellbeing

  • In fact, without the optimism bias, we would all be slightly depressed. People with mild depression, they don't have a bias when they look into the future

  • They're actually more realistic than healthy individuals.

  • But individuals with severe depression, they have a pessimistic bias.

  • So they tend to expect the future to be worse than it ends up being.

  • So optimism changes subjective reality. The way we expect the world to be changes the way we see it.

  • But it also changes objective reality. It acts as a self-fulfilling prophecy.

  • . And that is the third reason why lowering your expectations will not make you happy.

  • Controlled experiments have shown that optimism is not only related to success

  • it leads to success. Optimism leads to success in academia and sports and politics.

  • And maybe the most surprising benefit of optimism is health. If we expect the future to be bright, stress and anxiety are reduced.

  • So all in all, optimism has lots of benefits.

  • But the question that was really confusing to me was, how do we maintain optimism in the face of reality?

  • As an neuroscientist, this was especially confusing, because according to all the theories out there

  • when your expectations are not met, you should alter them.

  • But this is not what we find

  • We asked people to come into our lab in order to try and figure out what was going on.

  • We asked them to estimate their likelihood of experiencing different terrible events in their lives

  • So, for example, what is your likelihood of suffering from cancer?

  • And then we told them the average likelihood of someone like them to suffer these misfortunes.

  • So cancer, for example, is about 30 percent. And then we asked them again, "How likely are you to suffer from cancer?"

  • What we wanted to know was whether people will take the information that we gave them to change their beliefs.

  • And indeed they did -- but mostly when the information we gave them was better than what they expected.

  • So for example, if someone said, "My likelihood of suffering from cancer is about 50 percent,"

  • and we said, "Hey, good news. The average likelihood is only 30 percent," the next time around they would say

  • Well maybe my likelihood is about 35 percent." So they learned quickly and efficiently.

  • But if someone started off saying, "My average likelihood of suffering from cancer is about 10 percent,"

  • and we said, "Hey, bad news. The average likelihood is about 30 percent," the next time around they would say

  • Yep. Still think it's about 11 percent

  • So it's not that they didn't learn at all -- they did

  • but much, much less than when we gave them positive information about the future

  • And it's not that they didn't remember the numbers that we gave them;

  • everyone remembers that the average likelihood of cancer is about 30 percent and the average likelihood of divorce is about 40 percent

  • But they didn't think that those numbers were related to them.

  • What this means is that warning signs such as these may only have limited impact

  • Yes, smoking kills, but mostly it kills the other guy.

  • What I wanted to know was what was going on inside the human brain that prevented us from taking these warning signs personally

  • . But at the same time, when we hear that the housing market is hopeful, we think

  • Oh, my house is definitely going to double in price

  • To try and figure that out, I asked the participants in the experiment to lie in a brain imaging scanner

  • It looks like this. And using a method called functional MRI

  • we were able to identify regions in the brain that were responding to positive information.

  • One of these regions is called the left inferior frontal gyrus

  • So if someone said, "My likelihood of suffering from cancer is 50 percent

  • and we said, "Hey, good news. Average likelihood is 30 percent,"

  • the left inferior frontal gyrus would respond fiercely

  • And it didn't matter if you're an extreme optimist, a mild optimist or slightly pessimistic,

  • everyone's left inferior frontal gyrus was functioning perfectly well, whether you're Barack Obama or Woody Allen.

  • On the other side of the brain, the right inferior frontal gyrus was responding to bad news

  • And here's the thing: it wasn't doing a very good job

  • The more optimistic you were, the less likely this region was to respond to unexpected negative information

  • And if your brain is failing at integrating bad news about the future, you will constantly leave your rose-tinted spectacles on.

  • So we wanted to know, could we change this?

  • Could we alter people's optimism bias by interfering with the brain activity in these regions?

  • And there's a way for us to do that.

  • This is my collaborator Ryota Kanai.

  • And what he's doing is he's passing a small magnetic pulse through the skull of the participant in our study into their inferior frontal gyrus.

  • And by doing that, he's interfering with the activity of this brain region for about half an hour

  • After that everything goes back to normal, I assure you.

  • So let's see what happens. First of all, I'm going to show you the average amount of bias that we see.

  • So if I was to test all of you now, this is the amount that you would learn more from good news relative to bad news.

  • Now we interfere with the region that we found to integrate negative information in this task, and the optimism bias grew even larger.

  • We made people more biased in the way that they process information.

  • Then we interfered with the brain region that we found to integrate good news in this task, and the optimism bias disappeared

  • We were quite amazed by these results because we were able to eliminate a deep-rooted bias in humans.

  • And at this point we stopped and we asked ourselves, would we want to shatter the optimism illusion into tiny little bits?

  • If we could do that, would we want to take people's optimism bias away?

  • Well I've already told you about all of the benefits of the optimism bias,

  • which probably makes you want to hold onto it for dear life. But there are,

  • of course, pitfalls, and it would be really foolish of us to ignore them.

  • Take for example this email I received from a firefighter here in California.

  • He says, "Fatality investigations for firefighters often include 'We didn't think the fire was going to do that,'

  • even when all of the available information was there to make safe decisions.

  • This captain is going to use our findings on the optimism bias to try to explain to the firefighters why they think the way they do

  • to make them acutely aware of this very optimistic bias in humans.

  • So unrealistic optimism can lead to risky behavior, to financial collapse, to faulty planning.

  • The British government, for example

  • has acknowledged that the optimism bias can make individuals more likely to underestimate the costs and durations of projects.

  • So they have adjusted the 2012 Olympic budget for the optimism bias.

  • My friend who's getting married in a few weeks has done the same for his wedding budget.

  • And by the way, when I asked him about his own likelihood of divorce,

  • he said he was quite sure it was zero percent.

  • So what we would really like to do, is we would like to protect ourselves from the dangers of optimism,

  • but at the same time remain hopeful, benefiting from the many fruits of optimism.

  • And I believe there's a way for us to do that. The key here really is knowledge.

  • We're not born with an innate understanding of our biases

  • These have to be identified by scientific investigation

  • But the good news is that becoming aware of the optimism bias does not shatter the illusion. It's like visual illusions

  • in which understanding them does not make them go away

  • And this is good because it means we should be able to strike a balance

  • to come up with plans and rules to protect ourselves from unrealistic optimism, but at the same time remain hopeful.

  • I think this cartoon portrays it nicely

  • Because if you're one of these pessimistic penguins up there who just does not believe they can fly

  • Youll certainly never will. Because to make any kind of progress, we need to be able to imagine a different reality

  • and then we need to believe that that reality is possible.

  • But if you are an extreme optimistic penguin who just jumps down blindly hoping for the best,

  • you might find yourself in a bit of a mess when you hit the ground

  • But if you're an optimistic penguin who believes they can fly,

  • but then adjusts a parachute to your back just in case things don't work out exactly as you had planned,

  • you will soar like an eagle, even if you're just a penguin.

  • Thank you.

I'm going to talk to you about optimism -- or more precisely

Subtitles and vocabulary

B1 INT optimism bias likelihood percent optimistic divorce

【TED】Tali Sharot: The optimism bias (The optimism bias | Tali Sharot)

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    Go Tutor   posted on 2014/12/11
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