TED2012
Tali Sharot: The optimism bias
Tali Sharot: 乐观的偏见
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我们是否生来就乐观有余而现实不足？Tali Sharot与我们分享的最新研究表明：人类的大脑更倾向于接受乐观的信息，而这样的特点既对人有益又十分危险。
Tali Sharot - Cognitive neuroscientist
Tali Sharot studies why our brains are biased toward optimism. Full bio
Tali Sharot studies why our brains are biased toward optimism. Full bio
Double-click the English transcript below to play the video.
00:16
I'm going to talk to you about optimism --
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今天我讲演的主题是乐观——
00:19
or more precisely, the optimism bias.
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准确的说，乐观的偏见。
00:21
It's a cognitive illusion
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过去的几年中
00:23
that we've been studying in my lab for the past few years,
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我们都在实验室中研究这种认知错觉，
00:26
and 80 percent of us have it.
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百分之八十的人都有这种乐观偏见。
00:28
It's our tendency to overestimate
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我们倾向于高估
00:30
our likelihood of experiencing good events in our lives
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生活中发生好事的几率
00:33
and underestimate our likelihood of experiencing bad events.
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低估坏事发生的几率。
00:37
So we underestimate our likelihood of suffering from cancer,
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所以我们会低估我们患上癌症，
00:40
being in a car accident.
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遭遇车祸的几率。
00:42
We overestimate our longevity, our career prospects.
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在寿命和事业前景上，我们则会过于乐观。
00:45
In short, we're more optimistic than realistic,
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简而言之，我们过于乐观，不够现实
00:48
but we are oblivious to the fact.
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而且还浑然不觉。
00:51
Take marriage for example.
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以婚姻为例。
00:53
In the Western world, divorce rates are about 40 percent.
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在西方世界，离婚率大约是百分之四十。
00:56
That means that out of five married couples,
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也就是说每五对夫妇中，
01:00
two will end up splitting their assets.
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有两对最终要闹到分割财产。
01:03
But when you ask newlyweds about their own likelihood of divorce,
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但是如果你问新婚夫妇他们离婚的几率是多少的话，
01:06
they estimate it at zero percent.
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他们的估计是百分之零。
01:10
And even divorce lawyers, who should really know better,
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而且就连应该对这个问题有清醒认识的离婚律师
01:13
hugely underestimate their own likelihood of divorce.
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也会严重低估他们自己离婚的几率。
01:17
So it turns out that optimists are not less likely to divorce,
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实际上乐观主义者离婚的几率并不低，
01:20
but they are more likely to remarry.
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但再婚的几率比较高。
01:23
In the words of Samuel Johnson,
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用Samuel Johnson（英国作家）的话来说，
01:25
"Remarriage is the triumph of hope over experience."
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“再婚是希望战胜了经验。”
01:29
(Laughter)
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（笑声）
01:31
So if we're married, we're more likely to have kids.
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结婚之后很可能会生孩子。
01:36
And we all think our kids will be especially talented.
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我们都认为自己的孩子会才华横溢。
01:39
This, by the way, is my two-year-old nephew, Guy.
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顺便一提，这是我两岁的侄子Guy。
01:42
And I just want to make it absolutely clear
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我必须强调
01:44
that he's a really bad example of the optimism bias,
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用他来证明乐观偏见是一个非常糟糕的选择，
01:47
because he is in fact uniquely talented.
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因为事实上他确实拥有与众不同的才华。
01:50
(Laughter)
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（笑声）
01:51
And I'm not alone.
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我不是唯一一个这样想的人。
01:53
Out of four British people, three said
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四个英国人中有三个表示
01:55
that they were optimistic about the future of their own families.
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他们对自己家庭的未来感到乐观。
01:59
That's 75 percent.
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也就是百分之七十五。
02:01
But only 30 percent said
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不过只有百分之三十的人表示
02:03
that they thought families in general
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他们认为现在的家庭
02:05
are doing better than a few generations ago.
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比几十年前的家庭过的更好。
02:08
And this is a really important point,
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这一点非常重要，
02:10
because we're optimistic about ourselves,
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因为我们对自己，
02:11
we're optimistic about our kids,
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自己的孩子
02:13
we're optimistic about our families,
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和自己的家庭都很乐观，
02:15
but we're not so optimistic about the guy sitting next to us,
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然而对于坐在我们旁边的人，我们就没有那么乐观了，
02:18
and we're somewhat pessimistic
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而且我们对他人和国家的命运
02:20
about the fate of our fellow citizens and the fate of our country.
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甚至有些悲观。
02:24
But private optimism about our own personal future
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然而这种针对我们个人未来的个人化乐观
02:28
remains persistent.
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相当顽固。
02:30
And it doesn't mean that we think things will magically turn out okay,
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这并不意味着我们认为事情会变魔术一样莫名奇妙的顺利解决。
02:34
but rather that we have the unique ability to make it so.
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我们相信自己拥有取得成功的独特能力。
02:39
Now I'm a scientist, I do experiments.
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我是科学家，我做实验。
02:41
So to show you what I mean,
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所以为了说明我的观点，
02:43
I'm going to do an experiment here with you.
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我马上就和你们一起做一个实验。
02:46
So I'm going to give you a list of abilities and characteristics,
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我会列出一些能力和性格特点，
02:50
and I want you to think for each of these abilities
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我希望你们对照这个清单思考一下
02:53
where you stand relative to the rest of the population.
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自己的每一项能力处于人群中的什么位置。
02:57
The first one is getting along well with others.
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第一个是和他人和睦相处。
03:01
Who here believes they're at the bottom 25 percent?
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认为自己处于最差的百分之二十五的请举手。
03:07
Okay, that's about 10 people out of 1,500.
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好的，一千五百个人里面大概有十个人举手。
03:11
Who believes they're at the top 25 percent?
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认为自己处于最好的百分之二十五的呢？
03:15
That's most of us here.
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大多数人都举手了。
03:18
Okay, now do the same for your driving ability.
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好的，那再考量一下你的驾驶技术。
03:22
How interesting are you?
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你有趣吗？
03:25
How attractive are you?
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你迷人吗？
03:28
How honest are you?
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你诚实吗？
03:31
And finally, how modest are you?
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最后一个问题，你谦虚吗？
03:36
So most of us put ourselves above average
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所以多数人都认为自己的大部分能力
03:39
on most of these abilities.
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高于平均水平。
03:41
Now this is statistically impossible.
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但从统计学的角度上来说，这是不可能的。
03:43
We can't all be better than everyone else.
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不可能所有人都比其他人优秀。
03:46
(Laughter)
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（笑声）
03:48
But if we believe we're better than the other guy,
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但是如果我们相信自己比别人更优秀，
03:50
well that means that we're more likely to get that promotion, to remain married,
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这也就意味着我们认为自己更应该得到升职，婚姻美满，
03:54
because we're more social, more interesting.
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因为我们性格更有趣，更善于与人交往。
03:57
And it's a global phenomenon.
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这是一个国际性的现象。
03:59
The optimism bias has been observed
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我们可以在来自很多不同国家的人身上
04:02
in many different countries --
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找到乐观偏见——
04:03
in Western cultures, in non-Western cultures,
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无论他来自西方文化还是非西方文化，
04:06
in females and males,
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是男是女，
04:08
in kids, in the elderly.
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是孩子还是老人。
04:10
It's quite widespread.
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这种现象相当普遍。
04:11
But the question is, is it good for us?
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然而问题是，乐观偏见对我们有益吗？
04:15
So some people say no.
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有人认为没有好处。
04:17
Some people say the secret to happiness
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有人认为快乐的秘密就是
04:20
is low expectations.
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不要期望太高。
04:23
I think the logic goes something like this:
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他们的逻辑大概是这样的：
04:25
If we don't expect greatness,
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如果我们不期待成就什么伟业，
04:27
if we don't expect to find love and be healthy and successful,
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不期待找到爱人，身体健康，取得成功，
04:31
well we're not going to be disappointed when these things don't happen.
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我们得不到这些东西的时候也不会特别失望。
04:34
And if we're not disappointed when good things don't happen,
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如果好事没有到来我们却不失望
04:38
and we're pleasantly surprised when they do,
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那么好事发生的时候我们就得到了一个惊喜，
04:40
we will be happy.
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应该很开心。
04:42
So it's a very good theory,
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这个理论听起来很有道理，
04:43
but it turns out to be wrong for three reasons.
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但其实是错误的，原因有以下三点。
04:46
Number one: Whatever happens, whether you succeed or you fail,
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第一：无论成功还是失败，
04:51
people with high expectations always feel better.
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期望高的人都更加快乐。
04:55
Because how we feel when we get dumped or win employee of the month
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因为无论是失恋还是当选每月员工
04:59
depends on how we interpret that event.
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我们感觉如何取决于我们如何解读这一事件。
05:02
The psychologists Margaret Marshall and John Brown
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心理学家Margaret Marshall和John Brown
05:06
studied students with high and low expectations.
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完成了一项以期望值各异的学生为对象的研究。
05:09
And they found that when people with high expectations succeed,
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他们发现，当拥有高期望值的人成功的时候，
05:13
they attribute that success to their own traits.
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他们认为是自己的能力造就了这样的结果。
05:16
"I'm a genius, therefore I got an A,
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“我是天才，所以我得到了A，
05:18
therefore I'll get an A again and again in the future."
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因此我以后也会一直得A。“
05:21
When they failed, it wasn't because they were dumb,
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失败了也不代表他们愚蠢，
05:24
but because the exam just happened to be unfair.
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不过是考试恰巧不公平而已。
05:27
Next time they will do better.
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下一次他们一定会考好。
05:29
People with low expectations do the opposite.
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期望值低的人的思维正好相反。
05:32
So when they failed it was because they were dumb,
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失败是因为他们笨，
05:35
and when they succeeded
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成功则是
05:37
it was because the exam just happened to be really easy.
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因为考试恰巧特别简单。
05:40
Next time reality would catch up with them.
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下次他们就没这么幸运了。
05:42
So they felt worse.
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所以他们的感觉更糟糕。
05:44
Number two: Regardless of the outcome,
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第二：无论结果如何，
05:48
the pure act of anticipation makes us happy.
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心怀期待的感觉就让我们感到快乐。
05:52
The behavioral economist George Lowenstein
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行为经济学家George Lowenstein
05:55
asked students in his university
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请他的学生
05:57
to imagine getting a passionate kiss from a celebrity, any celebrity.
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想象和一位名人激情接吻，任何名人都可以。
06:01
Then he said, "How much are you willing to pay
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然后他问，”如果立刻就得到
06:04
to get a kiss from a celebrity
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和名人接吻的机会
06:06
if the kiss was delivered immediately,
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你愿意付多少钱？
06:08
in three hours, in 24 hours, in three days,
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三小时后呢？二十四小时后呢？三天后呢？
06:13
in one year, in 10 years?
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一年后呢？十年后呢？“
06:15
He found that the students were willing to pay the most
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他发现，三天后接吻，
06:19
not to get a kiss immediately,
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而非立刻接吻，
06:21
but to get a kiss in three days.
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价码最高。
06:24
They were willing to pay extra in order to wait.
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他们愿意为等待承担额外的费用。
06:28
Now they weren't willing to wait a year or 10 years;
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他们不愿意等一年或者十年；
06:31
no one wants an aging celebrity.
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没人希望亲吻一个人老珠黄的名人。
06:32
But three days seemed to be the optimum amount.
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不过三天似乎就是最合适的等待时间。
06:37
So why is that?
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为什么呢？
06:39
Well if you get the kiss now, it's over and done with.
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如果立刻就得到这个吻，美妙的时刻马上就结束了。
06:43
But if you get the kiss in three days,
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如果你三天后才会得到这个吻，
06:45
well that's three days of jittery anticipation, the thrill of the wait.
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这三天你都会因为期待而惴惴不安，因为等待而激动不已。
06:49
The students wanted that time
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学生们希望能有时间
06:51
to imagine where is it going to happen,
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想象接吻的方式
06:53
how is it going to happen.
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和发生的场景。
06:55
Anticipation made them happy.
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期待让他们感到快乐。
06:57
This is, by the way, why people prefer Friday to Sunday.
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顺便一提，相较于周日人们更喜欢周五也是同样的道理。
07:01
It's a really curious fact,
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这个现象非常有趣，
07:03
because Friday is a day of work and Sunday is a day of pleasure,
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因为周五是工作日，周日是休息日，
07:06
so you'd assume that people will prefer Sunday,
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所以人们似乎应该更喜欢周日，
07:09
but they don't.
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然而事实却不是这样。
07:11
It's not because they really, really like being in the office
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这并不是因为大家都喜欢呆在办公室里，
07:14
and they can't stand strolling in the park
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不能忍受在公园散步
07:16
or having a lazy brunch.
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或者享受一顿慵懒的早午餐。
07:17
We know that, because when you ask people
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这一点我们都明白，因为如果你问普通人
07:20
about their ultimate favorite day of the week,
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最喜欢一周之中的哪一天，
07:22
surprise, surprise, Saturday comes in at first,
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不出所料，星期六最受欢迎，
07:25
then Friday, then Sunday.
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其次是周五，再其次才是周日。
07:28
People prefer Friday
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人们喜欢周五是因为
07:30
because Friday brings with it the anticipation of the weekend ahead,
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周五会让你对眼前的周末
07:34
all the plans that you have.
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以及你的周末计划充满期待。
07:36
On Sunday, the only thing you can look forward to
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而周日你所能期待的只有
07:38
is the work week.
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新一周的工作。
07:41
So optimists are people who expect more kisses in their future,
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所以乐观主义者认为未来还有更多的亲吻的机会
07:46
more strolls in the park.
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更多在公园里散步的时间。
07:48
And that anticipation enhances their wellbeing.
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这种期待会提高他们的生活质量。
07:51
In fact, without the optimism bias,
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事实上，如果没有乐观偏见，
07:54
we would all be slightly depressed.
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我们都处于轻度抑郁的状态。
07:57
People with mild depression,
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轻度抑郁的人
07:59
they don't have a bias when they look into the future.
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展望未来的时候没有偏见。
08:02
They're actually more realistic than healthy individuals.
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事实上，他们比健康的人更加现实。
08:07
But individuals with severe depression,
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但是严重抑郁的人
08:09
they have a pessimistic bias.
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有悲观偏见。
08:11
So they tend to expect the future
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所以他们眼中的未来
08:13
to be worse than it ends up being.
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比实际更糟糕。
08:15
So optimism changes subjective reality.
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因此乐观可能改变主观现实。
08:19
The way we expect the world to be changes the way we see it.
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我们对世界的期待改变我们对世界的看法。
08:22
But it also changes objective reality.
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但它也会改变客观现实。
08:26
It acts as a self-fulfilling prophecy.
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是一种可能因为人们的主观想法而客观实现的预言。
08:28
And that is the third reason
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这也就是降低期待不会让你快乐的
08:31
why lowering your expectations will not make you happy.
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第三个原因。
08:34
Controlled experiments have shown
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对照试验表明
08:36
that optimism is not only related to success,
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乐观不仅与成功有关，
08:38
it leads to success.
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更是成功的诱因。
08:40
Optimism leads to success in academia and sports and politics.
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在学术界、体坛和政坛，乐观能都带来成功。
08:45
And maybe the most surprising benefit of optimism is health.
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也许乐观带来的最出人意料的好处就是健康。
08:50
If we expect the future to be bright,
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对美好未来的期待
08:53
stress and anxiety are reduced.
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可以舒缓压力、缓解焦虑。
08:56
So all in all, optimism has lots of benefits.
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因此，乐观益处多多。
09:00
But the question that was really confusing to me was,
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然而对我来说最令人困惑的问题是
09:03
how do we maintain optimism in the face of reality?
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我们如何在现实面前保持乐观的心态？
09:08
As an neuroscientist, this was especially confusing,
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作为一位神经学家这个问题尤其难以理解，
09:11
because according to all the theories out there,
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因为根据现有的理论
09:13
when your expectations are not met, you should alter them.
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如果期望没有成真的话，人会做出相应的调整。
09:18
But this is not what we find.
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然而我们的发现却不是这样。
09:19
We asked people to come into our lab
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为了了解这一切的原理
09:23
in order to try and figure out what was going on.
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我们请普通人走进实验室参与实验。
09:26
We asked them to estimate their likelihood
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我们请他们估计自己
09:28
of experiencing different terrible events in their lives.
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在生活中经历各种不幸的几率。
09:31
So, for example, what is your likelihood of suffering from cancer?
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比如，你得癌症的几率是多大？
09:35
And then we told them the average likelihood
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然后我们告诉他，和他各方面条件相似的人
09:37
of someone like them to suffer these misfortunes.
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经历这种不幸事件的平均几率。
09:40
So cancer, for example, is about 30 percent.
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比如说，得癌症的几率是百分之三十。
09:44
And then we asked them again,
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然后我们请他们再次估计自己患病的几率，
09:47
"How likely are you to suffer from cancer?"
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“你得癌症的几率是多少？”
09:50
What we wanted to know was
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我们希望了解的是
09:52
whether people will take the information that we gave them
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人们是否接受我们给他们的数据
09:55
to change their beliefs.
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并调整他们的想法。
09:57
And indeed they did --
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他们确实这样做了——
09:59
but mostly when the information we gave them
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但主要是在我们给他们的数据优于
10:02
was better than what they expected.
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他们自己的估计的情况下。
10:04
So for example,
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因此，比如
10:06
if someone said, "My likelihood of suffering from cancer
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如果人一个人说，“我得癌症的几率
10:09
is about 50 percent,"
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大约是百分之五十，”
10:11
and we said, "Hey, good news.
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然而我们告诉他，“嗨，好消息。
10:14
The average likelihood is only 30 percent,"
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平均几率只有百分之三十，”
10:16
the next time around they would say,
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下一次再问他的时候他会说，
10:18
"Well maybe my likelihood is about 35 percent."
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“那么我患病的几率大约是百分之三十五。”
10:21
So they learned quickly and efficiently.
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所以他们快速高效的接受了信息。
10:24
But if someone started off saying,
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但是如果有人开始说，
10:26
"My average likelihood of suffering from cancer is about 10 percent,"
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“我患癌症的几率大约是百分之十，”
10:30
and we said, "Hey, bad news.
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然而我们告诉他，“嗨，坏消息。
10:32
The average likelihood is about 30 percent,"
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平均患病几率是百分之三十，“
10:35
the next time around they would say,
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第二次被问到的时候他会说，
10:37
"Yep. Still think it's about 11 percent."
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“好。我还是觉得在百分之十一左右。”
10:41
(Laughter)
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（笑声）
10:42
So it's not that they didn't learn at all -- they did --
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因此他们并不是完全不接受新信息——
10:46
but much, much less than when we gave them
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他们只是更愿意接受
10:48
positive information about the future.
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有关未来的积极乐观的信息。
10:50
And it's not that they didn't remember the numbers that we gave them;
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他们没有忘掉我们提供的数据；
10:53
everyone remembers that the average likelihood of cancer
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每个人都记得患癌症的平均几率是
10:56
is about 30 percent
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百分之三十左右
10:58
and the average likelihood of divorce is about 40 percent.
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离婚率是百分之四十左右。
11:01
But they didn't think that those numbers were related to them.
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但他们不认为这些数据与自己有关。
11:05
What this means is that warning signs such as these
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这意味着，此类预警信号的
11:10
may only have limited impact.
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功效有限。
11:12
Yes, smoking kills, but mostly it kills the other guy.
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是的，香烟是一大杀手，但只有其他人会因抽烟丧命。
11:17
What I wanted to know was
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我想了解的是
11:18
what was going on inside the human brain
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人脑中到底发生了什么
11:21
that prevented us from taking these warning signs personally.
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以至于我们无法把预警信号与自身联系起来。
11:25
But at the same time,
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但是
11:27
when we hear that the housing market is hopeful,
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如果我们听说房地产市场很火爆，
11:29
we think, "Oh, my house is definitely going to double in price."
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我们就会认为：“哦，我房子的价值肯定会翻番。”
11:33
To try and figure that out,
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为了了解其中的原理
11:35
I asked the participants in the experiment
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我请实验参与者
11:38
to lie in a brain imaging scanner.
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躺在脑部成像扫描仪中。
11:40
It looks like this.
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看起来就像这样。
11:41
And using a method called functional MRI,
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通过功能性核磁成像，
11:44
we were able to identify regions in the brain
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我们可以而找到大脑中
11:48
that were responding to positive information.
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对积极信息作出反应的区域。
11:51
One of these regions is called the left inferior frontal gyrus.
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左额下回就是这种区域之一。
11:54
So if someone said, "My likelihood of suffering from cancer is 50 percent,"
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因此如果有人说，“我患癌症的几率是百分之五十，”
11:58
and we said, "Hey, good news.
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而我们告诉他，“嗨，好消息。
12:00
Average likelihood is 30 percent,"
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平均几率是百分之三会，“
12:02
the left inferior frontal gyrus would respond fiercely.
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左额下回就会有明显的反应。
12:06
And it didn't matter if you're an extreme optimist, a mild optimist
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无论你是极端乐观、一般乐观
12:10
or slightly pessimistic,
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还是轻度悲观，
12:12
everyone's left inferior frontal gyrus
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无论是你是巴拉克·奥巴马（Barack Obama）还是伍迪·艾伦（Woody Allen），
12:15
was functioning perfectly well,
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每个人的左额下回
12:17
whether you're Barack Obama or Woody Allen.
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都运转正常。
12:20
On the other side of the brain,
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在大脑的另外一侧，
12:21
the right inferior frontal gyrus was responding to bad news.
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右额下回负责对坏消息做出反应。
12:26
And here's the thing: it wasn't doing a very good job.
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问题就是处在这里：右额下回没能尽忠职守。
12:30
The more optimistic you were,
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你越乐观，
12:32
the less likely this region was
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这一区域
12:34
to respond to unexpected negative information.
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对意外的消极信息的反应就越迟钝。
12:37
And if your brain is failing
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如果你的大脑
12:40
at integrating bad news about the future,
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无法接受有关未来的坏消息，
12:43
you will constantly leave your rose-tinted spectacles on.
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你对世界的看法一直都会比实际美好。
12:48
So we wanted to know, could we change this?
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因此，我们希望进一步了解，我们可以改变这种现象吗？
12:53
Could we alter people's optimism bias
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我们时候可以通过干涉这些区域的脑部活动
12:56
by interfering with the brain activity in these regions?
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来改变人们的乐观偏见呢？
13:00
And there's a way for us to do that.
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我们确实有办法做到。
13:03
This is my collaborator Ryota Kanai.
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这是我的合作伙伴Ryota Kanai。
13:06
And what he's doing is he's passing a small magnetic pulse
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他正在将微小的磁脉冲
13:10
through the skull of the participant in our study
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通过研究参与者的头骨
13:12
into their inferior frontal gyrus.
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传达到他们的额下回。
13:14
And by doing that,
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这样做
13:16
he's interfering with the activity of this brain region
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他可以影响该区域的脑活动
13:19
for about half an hour.
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大约半个小时。
13:20
After that everything goes back to normal, I assure you.
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此后一切恢复正常，我保证。
13:23
(Laughter)
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（笑声）
13:25
So let's see what happens.
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现在我们来看看接下来发生了什么。
13:28
First of all, I'm going to show you
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首先，这是
13:30
the average amount of bias that we see.
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一般的偏见水平。
13:33
So if I was to test all of you now,
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如果我现场测试你们，
13:36
this is the amount that you would learn
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你们接受的好消息
13:37
more from good news relative to bad news.
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就比坏消息多这么多。
13:41
Now we interfere with the region
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现在我们干扰
13:43
that we found to integrate negative information in this task,
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接受消极信息的区域
13:48
and the optimism bias grew even larger.
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乐观偏见就变得更加严重。
13:51
We made people more biased in the way that they process information.
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我们加重了人们处理信息时的偏见。
13:57
Then we interfered with the brain region
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然后我们干扰
13:59
that we found to integrate good news in this task,
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接受好消息的区域，
14:03
and the optimism bias disappeared.
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随后乐观偏见就消失了。
14:07
We were quite amazed by these results
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这样的结果让我们十分震惊
14:09
because we were able to eliminate
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因为我们可以去除
14:12
a deep-rooted bias in humans.
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一种根深蒂固的人类偏见。
14:15
And at this point we stopped and we asked ourselves,
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至此我们停下了脚步并扪心自问，
14:20
would we want to shatter the optimism illusion into tiny little bits?
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将乐观偏见彻底摧毁是一件好事吗？
14:25
If we could do that, would we want to take people's optimism bias away?
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如果可以实现，我们要夺走人们的乐观偏见吗？
14:30
Well I've already told you about all of the benefits of the optimism bias,
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我已经向你们介绍了乐观偏见的种种好处，
14:34
which probably makes you want to hold onto it for dear life.
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你们可能觉得它不可或缺。
14:39
But there are, of course, pitfalls,
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当然，乐观偏见也有它的缺陷，
14:41
and it would be really foolish of us to ignore them.
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而且忽略这些缺陷是十分不明智的。
14:44
Take for example this email I recieved
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比如，一位来自加州的消防员
14:47
from a firefighter here in California.
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给我发来这样一封电子邮件。
14:50
He says, "Fatality investigations for firefighters
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他说，”针对消防员的死伤调查
14:53
often include 'We didn't think the fire was going to do that,'
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常有这样的记述‘我们没有想到火灾中会出现这种情况，’
14:58
even when all of the available information
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然而事实上根据当时已有的信息
15:00
was there to make safe decisions."
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已经可以做出安全的决定了。“
15:02
This captain is going to use our findings on the optimism bias
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这位队长希望用我们有关乐观偏见的研究结果
15:06
to try to explain to the firefighters
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向消防员们解释
15:08
why they think the way they do,
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2209
他们思考模式背后的原理，
15:10
to make them acutely aware of this very optimistic bias in humans.
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让他们意识到人类的这种乐观偏见。
15:18
So unrealistic optimism can lead to risky behavior,
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因此不现实的乐观可能导致高风险行为、
15:23
to financial collapse, to faulty planning.
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经济崩溃、计划缺陷。
15:26
The British government, for example,
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例如，英国政府
15:28
has acknowledged that the optimism bias
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承认乐观偏见
15:31
can make individuals more likely
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3287
会让人
15:34
to underestimate the costs and durations of projects.
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4026
低估各种项目所需耗费的金钱和时间。
15:38
So they have adjusted the 2012 Olympic budget
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4254
他们考虑乐观偏见以后
15:43
for the optimism bias.
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2111
调整了2012年奥运会的预算。
15:45
My friend who's getting married in a few weeks
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2187
我的一位朋友几周以后就要结婚了
15:47
has done the same for his wedding budget.
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2434
他也因为同样的原因调整了婚礼的预算。
15:49
And by the way, when I asked him about his own likelihood of divorce,
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3062
顺便一提，当我问他，他离婚的几率大概是多少时，
15:52
he said he was quite sure it was zero percent.
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3560
他说他坚定的相信是百分之零。
15:56
So what we would really like to do,
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2417
所以我们所真正需要的
15:58
is we would like to protect ourselves from the dangers of optimism,
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4161
是在不成为乐观偏见的受害者的同时，
16:03
but at the same time remain hopeful,
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3228
保持内心充满希望的状态，
16:06
benefiting from the many fruits of optimism.
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2844
享受乐观带来的种种益处。
16:09
And I believe there's a way for us to do that.
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2804
我相信我们可以做到这一点。
16:11
The key here really is knowledge.
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知识是这个问题的关键。
16:14
We're not born with an innate understanding of our biases.
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我们不是生来就对人类的种种偏见有深入的认识，
16:17
These have to be identified by scientific investigation.
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科学研究可以帮助我们识别这些偏见。
16:21
But the good news is that becoming aware of the optimism bias
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4184
不过好消息是，认识乐观偏见
16:25
does not shatter the illusion.
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并不会破坏这种错觉。
16:27
It's like visual illusions,
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1548
就像视觉错觉一样，
16:28
in which understanding them does not make them go away.
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明白原理并不会消除错觉。
16:32
And this is good because it means
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2237
值得欣慰的是，
16:34
we should be able to strike a balance,
333
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2473
我们可以找到平衡
16:36
to come up with plans and rules
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制定计划和规则
16:39
to protect ourselves from unrealistic optimism,
335
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2783
不让自己成为不切实际的乐观的受害者，
16:42
but at the same time remain hopeful.
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3152
但同时保持内心充满希望的状态。
16:45
I think this cartoon portrays it nicely.
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我认为这幅卡通画很好的展示了这种观点。
16:48
Because if you're one of these pessimistic penguins up there
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3526
如果你是上面那些悲观的企鹅
16:52
who just does not believe they can fly,
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2119
根本不相信自己可以飞翔，
16:54
you certainly never will.
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那你肯定永远也飞不起来。
16:56
Because to make any kind of progress,
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我们必须有能力想象与现实不同的未来，
16:58
we need to be able to imagine a different reality,
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2350
相信我们的构想能够实现，
17:00
and then we need to believe that that reality is possible.
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3731
才能真正取得进展。
17:04
But if you are an extreme optimistic penguin
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3524
但是，如果你是一只极为乐观的企鹅
17:08
who just jumps down blindly hoping for the best,
345
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2762
听天由命的直接跳下悬崖，
17:10
you might find yourself in a bit of a mess when you hit the ground.
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4781
落地的时候场面恐怕不大好看。
17:15
But if you're an optimistic penguin
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1889
然而如果你是一只相信自己能飞
17:17
who believes they can fly,
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1796
的乐观企鹅
17:19
but then adjusts a parachute to your back
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2663
又背上了一个降落伞
17:22
just in case things don't work out exactly as you had planned,
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3017
以防事情的发展没有你想象的那么顺利，
17:25
you will soar like an eagle,
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你就会如雄鹰一般遨游天际，
17:26
even if you're just a penguin.
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尽管你不过是只企鹅。
17:29
Thank you.
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谢谢。
17:31
(Applause)
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（掌声）
ABOUT THE SPEAKER
Tali Sharot - Cognitive neuroscientistTali Sharot studies why our brains are biased toward optimism.
Why you should listen
Optimism bias is the belief that the future will be better, much better, than the past or present. And most of us display this bias. Neuroscientist Tali Sharot wants to know why: What is it about our brains that makes us overestimate the positive? She explores the question in her book The Optimism Bias: A Tour of the Irrationally Positive Brain.
In the book (and a 2011 TIME magazine cover story), she reviewed findings from both social science and neuroscience that point to an interesting conclusion: "our brains aren't just stamped by the past. They are constantly being shaped by the future." In her own work, she's interested in how our natural optimism actually shapes what we remember, and her interesting range of papers encompasses behavioral research (how likely we are to misremember major events) as well as medical findings -- like searching for the places in the brain where optimism lives. Sharot is a faculty member of the Department of Cognitive, Perceptual and Brain Sciences at University College London.
Tali Sharot | Speaker | TED.com