The optimism bias | Tali Sharot

Translator: Timothy Covell Reviewer: Morton Bast

譯者: Shin-Yuan Tzou 審譯者: Chen-Han Hsiao

I'm going to talk to you about optimism --

我想和你們談談樂觀主義--

or more precisely, the optimism bias.

或者更準確的說，樂觀偏見。

It's a cognitive illusion

這是個認知錯覺

that we've been studying in my lab for the past few years,

過去數年來一直在我的實驗室裏研究著，

and 80 percent of us have it.

我們之中有80%都得過。

It's our tendency to overestimate

我們容易高估

our likelihood of experiencing good events in our lives

可能是因為生活中所經歷的都是好事

and underestimate our likelihood of experiencing bad events.

卻低估了可能也會經歷到壞事

So we underestimate our likelihood of suffering from cancer,

所以我們低估了可能也會患有癌症

being in a car accident.

可能也會出車禍

We overestimate our longevity, our career prospects.

我們高估了壽命、職涯前景

In short, we're more optimistic than realistic,

簡言之，我們是樂觀多於實際

but we are oblivious to the fact.

但是我們都忽略了一個事實

Take marriage for example.

就拿婚姻來說

In the Western world, divorce rates are about 40 percent.

離婚率在西方世界大約是40%

That means that out of five married couples,

也就是說五對已婚夫妻中

two will end up splitting their assets.

有兩對會玩完了然後分財產

But when you ask newlyweds about their own likelihood of divorce,

但是當你問新婚夫妻他們本身的離婚可能性時

they estimate it at zero percent.

他們都說百分之百的不可能

And even divorce lawyers, who should really know better,

甚至連離婚律師，他才更應該真正的了解，

hugely underestimate their own likelihood of divorce.

也是大大地低估了他們自己離婚的可能性。

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

所以結論就是樂觀者不是不可能離婚

but they are more likely to remarry.

而是較可能再婚

In the words of Samuel Johnson,

塞謬耳‧約翰曾說過，

"Remarriage is the triumph of hope over experience."

“再婚是希望對經歷的勝利。”

(Laughter)

(觀眾大笑)

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

所以如果我們結了婚，就比較可能有小孩。

And we all think our kids will be especially talented.

而且都會認為我們的小孩特別聰明。

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

這一位，順便一提，是我的兩歲外甥，蓋。

And I just want to make it absolutely clear

我想說的只是

that he's a really bad example of the optimism bias,

他真的是樂觀偏見的壞榜樣

because he is in fact uniquely talented.

因為他真的是絕頂聰明。

(Laughter)

(觀眾大笑)

And I'm not alone.

而且不是只有我這麼認為

Out of four British people, three said

四個英國人中，有三個會說

that they were optimistic about the future of their own families.

他們對於自己家人的前途都相當樂觀

That's 75 percent.

這樣的比例有75%

But only 30 percent said

但只有30%的人說

that they thought families in general

他們認為一般說來家人

are doing better than a few generations ago.

做得比前幾代要好

And this is a really important point,

這真的是很重要的一點，

because we're optimistic about ourselves,

因為我們對自己樂觀，

we're optimistic about our kids,

我們對孩子樂觀，

we're optimistic about our families,

對我們的家人樂觀，

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

但是對坐在我們旁邊的人卻不是那麼樂觀，

and we're somewhat pessimistic

反而有些悲觀

about the fate of our fellow citizens and the fate of our country.

對我們的市民同胞的命運及國家的命運。

But private optimism about our own personal future

但是對於我們個人前途的私人樂觀

remains persistent.

仍然持續。

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

這並不是說我們認為事情會奇蹟般的變好，

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

而是我們有獨特的能力使它變好

Now I'm a scientist, I do experiments.

現在，我是個科學家，我做實驗。

So to show you what I mean,

所以為了告訴你們我的本意，

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

我在這裏要和你們一起做個實驗。

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

我打算列出一張能力和特性的清單，

and I want you to think for each of these abilities

我要你們想想看這些每個能力

where you stand relative to the rest of the population.

你所佔據的位置，與其它人相比

The first one is getting along well with others.

第一個是和他人相處得很好

Who here believes they're at the bottom 25 percent?

在座各位有誰相信自己是最底部的25%？

Okay, that's about 10 people out of 1,500.

好吧，那大概是1,500人中的10個

Who believes they're at the top 25 percent?

有誰相信自己是最頂端的25%?

That's most of us here.

這裏大部份人都相信。

Okay, now do the same for your driving ability.

好。 同樣的事也發生在你的駕駛能力上

How interesting are you?

你這個人有多有趣?

How attractive are you?

你有多少吸引力?

How honest are you?

你有多誠實?

And finally, how modest are you?

最後，你有多謙虛?

So most of us put ourselves above average

所以大部份的人把自己放在水平之上

on most of these abilities.

對這些能力來說

Now this is statistically impossible.

這是完全不可能的

We can't all be better than everyone else.

我們不可能次次比別人好

(Laughter)

(觀眾大笑)

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

但是如果我們相信自己比他人好

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

就是說我們容易高升、容易維持婚姻

because we're more social, more interesting.

因為我們較社會化、較有趣

And it's a global phenomenon.

這是個全球化的現象

The optimism bias has been observed

樂觀偏見已經被注意到了

in many different countries --

在許多不同的國家裏

in Western cultures, in non-Western cultures,

在西方文化裏、在非西方文化裏

in females and males,

在女性與男性之間

in kids, in the elderly.

在小孩和年長者之間

It's quite widespread.

分佈甚廣

But the question is, is it good for us?

但問題是，對我們而言好嗎?

So some people say no.

有些人說不好

Some people say the secret to happiness

有些人說幸福的秘訣

is low expectations.

就是期望不高

I think the logic goes something like this:

我想邏輯是這樣的：

If we don't expect greatness,

如果我們的期盼不高，

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

如果我們不期盼找到愛、身體健康和事業成功，

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

嗯，當這些事都沒發生時，我們就不會失望。

And if we're not disappointed when good things don't happen,

而且，就算好事沒發生時，我們也不會失望

and we're pleasantly surprised when they do,

如果發生了好事，就算給我們一個大驚喜

we will be happy.

我們會很快樂。

So it's a very good theory,

所以這是個相當好的推論，

but it turns out to be wrong for three reasons.

但是有三個理由讓它變成錯的。

Number one: Whatever happens, whether you succeed or you fail,

第一：不論發生什麼事，不管你成功還是失敗，

people with high expectations always feel better.

期待高的人通常都會自我感覺較好。

Because how we feel when we get dumped or win employee of the month

因為，我們被人拋棄或當上明星店員的感覺如何，

depends on how we interpret that event.

完全看我們怎麼解釋那件事而定

The psychologists Margaret Marshall and John Brown

心裡學家Margraret Marshall 及 John Brown

studied students with high and low expectations.

研究期盼高及期盼低的學生。

And they found that when people with high expectations succeed,

他發現期待高的人成功時，

they attribute that success to their own traits.

他們將成功歸功於自己的人格特質。

"I'm a genius, therefore I got an A,

’“我是個天才，所以我得個A，

therefore I'll get an A again and again in the future."

所以以後我也會一再得A。”

When they failed, it wasn't because they were dumb,

當他們失敗時，不是因為他們笨。

but because the exam just happened to be unfair.

而是因為這個考試剛巧不公平，

Next time they will do better.

下一次他們會考得更好。

People with low expectations do the opposite.

期盼低的人剛好相反。

So when they failed it was because they were dumb,

所以當他們失敗時他們就是笨，

and when they succeeded

而當他們成功時，

it was because the exam just happened to be really easy.

是因為考試剛巧真的太簡單，

Next time reality would catch up with them.

下一次就會露出馬腳了。

So they felt worse.

所以他們覺得很糟。

Number two: Regardless of the outcome,

第二：不管結果，

the pure act of anticipation makes us happy.

單純的期待行為使我們快樂，

The behavioral economist George Lowenstein

行為經濟學家George Lowenstein

asked students in his university

在大學裏問學生

to imagine getting a passionate kiss from a celebrity, any celebrity.

得到名人的熱吻的印象，任何名人

Then he said, "How much are you willing to pay

他說：“你願付多少錢

to get a kiss from a celebrity

得到名人的吻

if the kiss was delivered immediately,

如果吻馬上就來，

in three hours, in 24 hours, in three days,

3小時內，24小時內，3天內

in one year, in 10 years?

1年內，10年內？

He found that the students were willing to pay the most

他發現學生最願意付的是

not to get a kiss immediately,

不要馬上就能得到的吻

but to get a kiss in three days.

而是3天內能得到的吻，

They were willing to pay extra in order to wait.

也有人願意支付額外費用來等待一個吻

Now they weren't willing to wait a year or 10 years;

但他們不願意一等就等個1年或10年的；

no one wants an aging celebrity.

因為沒人會要個上了年紀的名人，

But three days seemed to be the optimum amount.

但是三天似乎是最佳的天數

So why is that?

為什麼會這樣?

Well if you get the kiss now, it's over and done with.

嗯。如果你現在馬上就被親一下，那一切就沒事了

But if you get the kiss in three days,

但是如果你三天內才被親

well that's three days of jittery anticipation, the thrill of the wait.

那就有三天緊張的預期，等待的快感

The students wanted that time

學生要那個時間

to imagine where is it going to happen,

來想像即將要發生什麼事，

how is it going to happen.

究竟是怎麼發生的。

Anticipation made them happy.

期待使他們快樂。

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

這也就是，順道一提的，為何人們比週日還喜歡週五。

It's a really curious fact,

這真是讓人難以理解的事實，

because Friday is a day of work and Sunday is a day of pleasure,

因為週五是個工作天而週日是個歡樂天，

so you'd assume that people will prefer Sunday,

所以可以假設人們較喜歡星期天，

but they don't.

但不是。

It's not because they really, really like being in the office

不是因為他們真的、真的愛呆在辦公室

and they can't stand strolling in the park

也不是因為他們不能忍受在公園裏散步

or having a lazy brunch.

或是不想吃個慵懶的早午餐

We know that, because when you ask people

我們知道，因為當你問人

about their ultimate favorite day of the week,

一週中最喜歡哪一天

surprise, surprise, Saturday comes in at first,

驚訝吧，驚訝吧，週六是首選，

then Friday, then Sunday.

之後是週五，再來才是週日，

People prefer Friday

人們喜歡週五

because Friday brings with it the anticipation of the weekend ahead,

因為週五為週末帶來期待，

all the plans that you have.

期待所有的計劃

On Sunday, the only thing you can look forward to

但在週日，唯一能企望到的

is the work week.

就是整週的工作。

So optimists are people who expect more kisses in their future,

所以樂觀者就是期待未來能有更多吻的人

more strolls in the park.

在公園裏更多的散步

And that anticipation enhances their wellbeing.

所以期待提高了他們的幸福感

In fact, without the optimism bias,

事實上，沒有了樂觀偏見

we would all be slightly depressed.

我們都會有一點點沮喪

People with mild depression,

輕度憂鬱症患者，

they don't have a bias when they look into the future.

當他們展望未來時完全沒有偏見

They're actually more realistic than healthy individuals.

實際上，他們比健康的人更現實

But individuals with severe depression,

但是重度憂鬱症患者

they have a pessimistic bias.

他們有悲觀的偏見

So they tend to expect the future

所以往往盼望前途

to be worse than it ends up being.

比死亡結束時要差

So optimism changes subjective reality.

所以樂觀改變了主觀的現實

The way we expect the world to be changes the way we see it.

我們期盼世界變成我們眼見的方式

But it also changes objective reality.

但是也改變了客觀存在

It acts as a self-fulfilling prophecy.

它表現得像個自我實現的預言

And that is the third reason

第三個理由

why lowering your expectations will not make you happy.

為什麼降低期待不會使你感到快樂

Controlled experiments have shown

對照實驗顯示

that optimism is not only related to success,

樂觀不只和成功有關，

it leads to success.

樂觀導向成功

Optimism leads to success in academia and sports and politics.

樂觀在學術界及運動界和政治界導向成功

And maybe the most surprising benefit of optimism is health.

樂觀最令人驚喜的好處就是健康

If we expect the future to be bright,

如果我們期盼前途是光明的

stress and anxiety are reduced.

壓力及焦慮會降低

So all in all, optimism has lots of benefits.

所以總而言之，樂觀有很多好處

But the question that was really confusing to me was,

但是真正困擾我的問題是

how do we maintain optimism in the face of reality?

我們如何在現實面前保持樂觀?

As an neuroscientist, this was especially confusing,

身為一個神經科學家，感到特別的困擾，

because according to all the theories out there,

因為根據那裏所有的理論

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

期待未達時，就應該改變他們

But this is not what we find.

但這不是我們所發現的

We asked people to come into our lab

我們要求人們來到實驗室

in order to try and figure out what was going on.

為的是嘗試而且弄清楚倒底是怎麼一回事

We asked them to estimate their likelihood

我們要求他們評估自己

of experiencing different terrible events in their lives.

經歷生活中不同的恐怖事件的可能性

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

例如，得癌症的可能性為何?

And then we told them the average likelihood

之後我們告訴他們像他們這樣的人

of someone like them to suffer these misfortunes.

遭受這些不幸的平均可能性

So cancer, for example, is about 30 percent.

所以癌症，舉例來說，大約30%

And then we asked them again,

之後我們再問他們一次，

"How likely are you to suffer from cancer?"

“得癌症的可能性有多大？”

What we wanted to know was

我們想知道的是

whether people will take the information that we gave them

人們是否會採信我們給的消息

to change their beliefs.

來改變他們的看法。

And indeed they did --

他們真的會

but mostly when the information we gave them

但大部份是在我們給他們的消息

was better than what they expected.

比他們期待的消息還要好的時候

So for example,

所以舉例來說

if someone said, "My likelihood of suffering from cancer

如果某人說，“我得癌症的可能性

is about 50 percent,"

大概是50%，”

and we said, "Hey, good news.

我們會說，“嘿，好消息。

The average likelihood is only 30 percent,"

平均可能性只有30%，”

the next time around they would say,

下一次大概他們就會說，

"Well maybe my likelihood is about 35 percent."

“嗯，我的可能性大約是35%，”

So they learned quickly and efficiently.

所以他們學得很快也很有效率

But if someone started off saying,

但是如果有人開始說

"My average likelihood of suffering from cancer is about 10 percent,"

“我得癌的一般可能性大約是10%，”

and we said, "Hey, bad news.

我們就會說“嗨，壞消息。

The average likelihood is about 30 percent,"

一般得病的可能性是30%

the next time around they would say,

到了下一次大概他們會說

"Yep. Still think it's about 11 percent."

是，我仍然認為大約是11%

(Laughter)

(全場觀眾大笑)

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

所以不是他們完全不知道--他們知道--

but much, much less than when we gave them

但是比我們告訴他們的

positive information about the future.

有關未來的正面信息要少很多

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

也不是他們不記得我們給他們的數字

everyone remembers that the average likelihood of cancer

每個人都記得癌症的平均可能性

is about 30 percent

大約是30%

and the average likelihood of divorce is about 40 percent.

而離婚的平均可能性大約是40%

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

但是他們不認為這些數字跟他們有關

What this means is that warning signs such as these

這表示像這樣的警告跡象

may only have limited impact.

影響也有限

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

是的，吸煙殺人，但是大部份是殺了別人

What I wanted to know was

我想知道的是

what was going on inside the human brain

人類腦中倒底發生了什麼事

that prevented us from taking these warning signs personally.

才會讓我們以為這些警告跡象不是衝著我們來的

But at the same time,

但是同時

when we hear that the housing market is hopeful,

當我們聽到房市很有希望的時候

we think, "Oh, my house is definitely going to double in price."

我們就會想，“喔，我的房子絕對漲了兩倍

To try and figure that out,

試著找出來

I asked the participants in the experiment

我要求實驗室裏的參與者

to lie in a brain imaging scanner.

躺在腦成像掃描儀裏

It looks like this.

看起來就像這樣

And using a method called functional MRI,

而且用一種叫做核磁共振的儀器

we were able to identify regions in the brain

我們可以辨認出腦中的哪些部位

that were responding to positive information.

回應了正面信息

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

其中一個部份被稱為左前下腦回

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

所以如果某人說，“我得癌的可能性是50%”

and we said, "Hey, good news.

我們會說，“嘿，好消息。”

Average likelihood is 30 percent,"

一般的可能性是30%”

the left inferior frontal gyrus would respond fiercely.

左前下腦回將強烈的回應

And it didn't matter if you're an extreme optimist, a mild optimist

就算你是個極端樂觀主義者，溫和的樂觀主義者，

or slightly pessimistic,

或是輕度的悲觀者 ，那都不重要

everyone's left inferior frontal gyrus

每個人的左前下腦回

was functioning perfectly well,

都運作得很好

whether you're Barack Obama or Woody Allen.

不管你是歐巴馬或是伍迪艾倫

On the other side of the brain,

在腦的另一邊

the right inferior frontal gyrus was responding to bad news.

右前下腦回只對壞消息有所回應

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

事情來了: 它做得不是很好

The more optimistic you were,

你愈是樂觀

the less likely this region was

這個部份就不太可能

to respond to unexpected negative information.

對意想不到的負面消息做出回應

And if your brain is failing

如果你的大腦

at integrating bad news about the future,

無法整合與未來有關的壞消息

you will constantly leave your rose-tinted spectacles on.

你就會一直保持樂觀

So we wanted to know, could we change this?

所以我們想知道，我們能改變嗎?

Could we alter people's optimism bias

我們能不能透過干擾這些部份的腦活動

by interfering with the brain activity in these regions?

來改變人們的樂觀偏見?

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

有一個方法

This is my collaborator Ryota Kanai.

這是我的合作人Ryota Kanai

And what he's doing is he's passing a small magnetic pulse

他正在做的就是把小型電磁脈衝

through the skull of the participant in our study

透過參加研究者的頭骨

into their inferior frontal gyrus.

傳送到他們的額下回

And by doing that,

這樣做

he's interfering with the activity of this brain region

他的這些大腦區域活動就會被干擾

for about half an hour.

大約半小時

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

我向你保證，之後每件事都回到正常

(Laughter)

(觀眾大笑)

So let's see what happens.

所以讓我們看看發生了什麼事

First of all, I'm going to show you

首先，我要給你們看的是

the average amount of bias that we see.

我們所見的偏見的平均量

So if I was to test all of you now,

所以如果現在我要試試你們所有的人

this is the amount that you would learn

這就是你們

more from good news relative to bad news.

相對於壞消息來說 聽到了更多好消息

Now we interfere with the region

現在我們來干擾一下

that we found to integrate negative information in this task,

我們找到的這個 整合負面消息的腦部區域

and the optimism bias grew even larger.

樂觀主義的偏見就會愈來愈大

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

我們使得人們在處理消息的方面更加偏激

Then we interfered with the brain region

所以我們干擾腦區域

that we found to integrate good news in this task,

我們找到的這個 整合負面消息的腦部區域

and the optimism bias disappeared.

而樂觀偏見就消失了

We were quite amazed by these results

我們對這些結果相當震驚

because we were able to eliminate

因為我們可以消除

a deep-rooted bias in humans.

人類根深蒂固的偏見

And at this point we stopped and we asked ourselves,

在這一點上我們停了下來而且問自己

would we want to shatter the optimism illusion into tiny little bits?

是不是要把樂觀的幻想粉碎成一小片一小片?

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

如果可以這樣做，我們會不會是想取走人們的樂觀偏見?

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

我已經告訴你樂觀偏見的所有好處

which probably makes you want to hold onto it for dear life.

你可能會想在寶貴的生活裏繼續保有

But there are, of course, pitfalls,

但是當然有圈套

and it would be really foolish of us to ignore them.

而我們真是蠢到忽略了他們

Take for example this email I recieved

舉個例子來說，我從一位加州的消防隊員

from a firefighter here in California.

收到這封電子郵件

He says, "Fatality investigations for firefighters

他說，“消防隊員的死亡調查

often include 'We didn't think the fire was going to do that,'

通常包括“我們不認為火勢會像這樣

even when all of the available information

即使所有現有的消息

was there to make safe decisions."

都是安全的

This captain is going to use our findings on the optimism bias

這位船長想使用我們在樂觀偏見上的研究結果

to try to explain to the firefighters

試著向消防隊員解釋

why they think the way they do,

為什麼他們會認為他們做事的方法

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

會使得他們敏銳地意識到人類的樂觀偏見

So unrealistic optimism can lead to risky behavior,

所以不切實際的樂觀會導致危險的行為

to financial collapse, to faulty planning.

導致金融崩潰，導致計劃錯誤

The British government, for example,

舉例來說，英國政府

has acknowledged that the optimism bias

確認樂觀偏見

can make individuals more likely

使得人們更有可能

to underestimate the costs and durations of projects.

低估了計劃的成本及持續期間

So they have adjusted the 2012 Olympic budget

所以他們調整了2012年奧林匹克的預算

for the optimism bias.

就是因為樂觀偏見

My friend who's getting married in a few weeks

我有一個將在幾星期內結婚的朋友

has done the same for his wedding budget.

也對結婚預算做了同樣的事

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

順便一提的是，當我問他自己離婚的可能性時

he said he was quite sure it was zero percent.

他說他很確定是百分之零(完全不可能)

So what we would really like to do,

所以我們真正想做的

is we would like to protect ourselves from the dangers of optimism,

是我們要保護自己免除樂觀危險

but at the same time remain hopeful,

但同時保持深具希望

benefiting from the many fruits of optimism.

從樂觀的許多成果中獲益

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

我相信一定有條路讓我們這樣做

The key here really is knowledge.

真正的關鍵是知識

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

我們不是生來就了解偏見

These have to be identified by scientific investigation.

這些必需要透過科學調查來釐清

But the good news is that becoming aware of the optimism bias

但是好消息是知道了樂觀偏見

does not shatter the illusion.

並未粉碎幻想

It's like visual illusions,

它就像是視覺上的錯覺

in which understanding them does not make them go away.

了解它們而非叫他們走

And this is good because it means

這是很好的因為意思是

we should be able to strike a balance,

我們應該能夠找到折衷辦法

to come up with plans and rules

想出計劃和規則

to protect ourselves from unrealistic optimism,

保護我們自己遠離不切實際的樂觀

but at the same time remain hopeful.

但同時保持深具希望

I think this cartoon portrays it nicely.

我認為這個卡通畫面很不錯

Because if you're one of these pessimistic penguins up there

因為如果你是站在那邊的悲觀企鵝的一員

who just does not believe they can fly,

就是不相信自己會飛

you certainly never will.

當然就永遠也不會飛

Because to make any kind of progress,

因為任何的進展

we need to be able to imagine a different reality,

都需要想像一個不同的現實

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

之後我們必需相信那個現實是可能的

But if you are an extreme optimistic penguin

但如果你是個極端樂觀的企鵝

who just jumps down blindly hoping for the best,

只是盲目的往下跳希望成為最好的

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

當撞到地面的時候，你會發現有點麻煩

But if you're an optimistic penguin

但如果你是個樂觀的企鵝

who believes they can fly,

相信自己可以飛

but then adjusts a parachute to your back

但之後又調整背後的降落傘

just in case things don't work out exactly as you had planned,

萬一事情不完全按照你的計劃走

you will soar like an eagle,

你也可能像隻鷹一樣的翱翔

even if you're just a penguin.

即使你只是隻企鵝

Thank you.

謝謝你

(Applause)

(觀眾鼓掌)