演讲题目：How Common Knowledge Shapes the World

演讲简介：

常识是社会生活的秘密动力源，它使我们能够协调从聚会到市场再到国际外交等方方面面的事务。在这场引人入胜的演讲中，实验认知科学家史蒂文·平克探讨了常识的重大影响，串联起了关于为何独裁者害怕空白标识、为何中央银行家会喃喃自语以及为何大声说出沉默的部分会破坏一段友谊的故事。他以机智和智慧的方式邀请我们更好地理解我们如何进入彼此的思维——以及当共同的规范动摇时意味着什么。



中英文字幕

When the little boy said the emperor was naked, he wasn't telling them anything they didn't already know.

当小男孩说皇帝赤身裸体时，他并没有告诉听众任何他们不知道的事情。

But he added to their knowledge nonetheless.

但他仍然增加了他们的知识。

By blurting out what everyone could see within earshot of the others,

通过脱口而出每个人在其他人听得到的范围内都能看到的内容，

he ensured that everyone knew that everyone else knew what they knew, that everyone knew that, and so on.

他确保了每个人都知道其他人都知道他们所知道的。

And that changed their relationship with the emperor from obsequious deference to ridicule and scorn.

这改变了他们与皇帝的关系从卑躬屈膝变成了嘲笑和蔑视。

Hans Christian Andersen's immortal story draws on a momentous logical distinction.

汉斯·克里斯蒂安·安徒生的不朽故事借鉴了重大的逻辑区别。

With private knowledge, I know something, and you know it.

有了个人知识，我知道一些事情，你也知道。

With common knowledge, I know that fact, and you know it, but in addition, I know that you know it, and you know that I know it,

根据常识，我知道这个事实，你也知道，但此外，我知道你知道，你也知道我知道，

and I know that you know that I know it, ad infinitum.

我知道你知道我知道的，而且是无限的

Of course, the reason that common knowledge is significant is that it is essential for coordination.

当然，共同知识之所以重要，是因为它对于协调至关重要。

In a classic example from Thomas Schelling, a couple is separated in Manhattan, incommunicado, and somehow must find each other.

托马斯·谢林的一个经典例子是，一对夫妇在曼哈顿走散了，无法与外界交流，并且必须以某种方式找到彼此。

Well, he knows that she likes to browse the aisles of certain bookstore, so he heads there.

他知道她喜欢浏览某家书店的过道，所以他就去了那里。

But then he realizes that she knows that he likes to hang out in a certain camera store,

但后来他意识到她知道他喜欢在某家相机店闲逛，

so he changes course until he figures that she will anticipate that he will guess that she will opt for the bookstore.

所以他改变了路线，直到他认为她会预料到他会猜测她会选择书店。

So he does another about face,

所以他又做了一件关于见面的事，

only for it to dawn on him that it will occur to her that he knows that she is aware that he likes to haunt the bookstore,

只是当他意识到她会意识到他知道她知道他喜欢出没在书店，

so he pirouettes once again.

于是他再次回来。

Meanwhile, she is whipsawed by the same futile empathy.

与此同时，她也被同样徒劳的同理心所震撼。

Nothing short of common knowledge can guarantee that they'll end up at the same place and at the same time.

除非常识，否则无法保证这些最终会在同一时间、同一地点发生。

Of course, no one can think an infinite Russian doll of "I know that she knows that I know that she knows" thoughts.

当然，没有人能想到一个俄罗斯套娃式的“我知道她知道我知道她知道”的想法。

Our heads start to spin with three or four layers, let alone an infinite number.

当层次达到三层或四层时，我们便开始晕头转向，更不用说无限多层了。

In a well-known episode of "Friends," Phoebe says to Rachel,

在《老友记》的一集中，菲比对雷切尔说：

"They don't know we know they know we know. Joey, you can't say anything!"

“他们不知道我们知道他们知道我们知道。乔伊，你什么也不能说！"

And he replies, "I couldn't even if I wanted to!"

他回答说：“即使我想说我也做不到啊！"

Instead, common knowledge can be captured in a simple mental intuition that something is public or conspicuous or out there,

相反，常识可以通过一种简单的心理直觉来捕捉，即某些东西是公开的或引人注目的或在那里，

and that can be conveyed by direct speech.

并且可以通过直接语音来表达。

In the case of our separated couple, a cell phone call.

在那对走散夫妇的情况下，一个电话就可以解决问题。

Indeed, solving coordination dilemmas may be the reason that language evolved in our species in the first place.

事实上，解决协调困境可能是语言在我们物种中进化的原因。

In the absence of a public event, the next best thing is conspicuous salience, or a focal point.

在没有公共活动的情况下，下一个最好的做法是引人注目的突出性或焦点。

Schelling suggests that our couple might gravitate toward the big clock in Grand Central Station,

谢林建议那对走散的夫妇可能会被中央车站的大本钟所吸引，

even if it wasn't particularly close to the point at which they'd been separated,

即使它不是特别接近他们被分开的那一点，

simply because each might anticipate that it would pop into the mind of the other.

仅仅是因为每个人都可能预料到它会突然出现在另一个人的脑海中。

A third solution is a convention.

第三个解决方案是公约。

A tacit agreement to do something in a certain way for no other reason than they have agreed to do it that way, which is reason enough.

它默认以某种方式做某事，没有其他原因，只是他们同意这样做，这就足够了。

Our separated couple might agree that should they ever be separated in the future,

那对走散的夫妇可能会同意，如果他们将来走散了，

they will adopt the convention of chivalry and go to the bookstore.

他们将会遵循绅士传统，一同前往书店。

Or patriarchy, and go to the camera store.

或是遵循父权传统，选择前往相机店。

Or whimsy, and go to a lost-and-found in a department store.

或是突发奇想，选择去商场的失物招领处。

Or fairness, and take turns or flip coins.

或是秉持公平原则，选择轮流决定或抛硬币解决。

At larger scales, common salience or focal points and conventions, drive a lot of our legal and financial coordination.

在更大的范围内，共同的突出点或焦点和惯例推动了我们的大量法律和财务协调。

An everyday example is driving on the left, or on the right.

一个日常的例子是向左行驶或向右行驶。

It doesn't matter as long as everyone agrees to drive on the same side,

只要每个人都同意在同一边开车，这并不重要，

as in the joke about the woman who calls her husband during his morning commute and says,

就像在一个笑话中，一个女人在丈夫早上通勤时给他打电话说：

"Be careful, honey. The radio says that there's a maniac driving on the wrong side of the freeway."

“小心，亲爱的。收音机说有一个疯子在高速公路的错误一边开车。"

And he says, "One maniac? There are hundreds of them."

他说：“一个疯子？有数百个啊。"

Another everyday example is money.

另一个日常例子是钱。

I accept a piece of paper in exchange for an old chair,

我接受一张纸来换取一把旧椅子，

because I know that my grocer will accept it in exchange for some groceries because he knows his supplier will accept it, and so on.

因为我知道我的杂货店老板会接受它来换取一些杂货，因为他知道他的供应商会接受它，等等。

Now not all the examples are this obvious.

现在并不是所有的例子都这么明显。

Why are autocrats terrified of public protests?

为什么独裁者害怕公众抗议？

Well the basic reason was explained by Gandhi in the eponymous movie when he said,

甘地在同名电影中解释了基本原因，他说，

"100,000 Englishmen cannot control 350 million Indians if the Indians refuse to cooperate."

“如果印度人拒绝合作，10万英国人就无法控制3.5亿印度人。"

The problem is that the Indians can't refuse to cooperate if each one fears that no one will join him.

问题是，如果每个人都担心没有人会加入他，印度人就不能拒绝合作。

In a public demonstration, each protester can see the other protesters see the other protesters,

在公开示威中，每个抗议者都可以看到其他抗议者，也可以看到另外抗议者，

and this common knowledge allows them to coordinate their resistance,

这种常识使他们能够协调抵抗，

whether by literally storming the palace or by bringing the apparatus of the state to a halt through boycotts and work stoppages.

无论是通过真正的冲击宫殿，还是通过抵制和停工使国家机器停止运转。

Another non-obvious example comes from the world of investing.

另一个不明显的例子来自投资领域。

John Maynard Keynes compared speculative investing to a newspaper beauty contest,

约翰·梅纳德·凯恩斯将投机性投资比作报纸选美比赛，

in which the winner is not the woman with the prettiest face but the contestant who chooses the face that is chosen by the greatest number of other contestants,

在这场竞争中，胜出者并非拥有最美脸庞的女子，而是选择了最多参赛者共同认可面容的选手。

each of whom is anticipating the choices of other contestants, and so on.

每个人都在期待其他参赛者的选择。

This can set off cycles of exuberant recursive mentalizing, as investors desperately search for focal points,

这便会触发旺盛递归性心理推测的循环——投资者们拼命寻找着共识焦点。

each one buying an investment not because of its inherent productive value but because they hope to unload it at a profit on future investors, greater fools.

每个人购买一项投资并不是因为它固有的生产价值，而是因为他们希望将其出售，让未来的投资者（更大的傻瓜）获利。

This can set everyone off in search of conspicuous focal points such as Super Bowl ads.

这可能会让每个人都开始寻找超级碗广告等显眼的焦点。

Everyone knows that everyone watches the Super Bowl.

每个人都知道每个人都在观看超级碗。

In 2022, cryptocurrency exchanges ran high-concept ads in which they tried to gin up a common expectation of rising prices not by touting any of the advantages of cryptocurrency but by warning,

2022年，加密货币交易所投放了高概念广告，试图通过警告来激发人们对价格上涨的共同预期，而不是通过宣扬加密货币的任何优势，

"Don't be like Larry. Don't miss out."

“不要像拉里一样。不要错过。"

Now, of course, it's only so long that an asset can levitate in midair, suspended by nothing but common expectation.

当然，现在，资产只能悬浮在半空中，除了共同的期望之外，什么也没有。

Bubbles pop when the market runs out of greater fools who don't want to miss out on the next best thing or when the doubt itself becomes common knowledge.

当市场上没有更大的傻瓜不想错过下一个最好的东西时，或者当怀疑本身成为常识时，泡沫就会破裂。

This can send investors running for the exits, each desperate to sell a security out of fear that everyone else is desperate to sell it.

这可能会导致投资者纷纷退出，每个人都急于出售证券，因为担心其他人都急于出售它。

The result can be a bank run or hyperinflation or a Great Depression.

结果可能是银行挤兑、恶性通货膨胀或大萧条。

When Franklin Delano Roosevelt said, "The only thing we have to fear is fear itself,"

当富兰克林·德拉诺·罗斯福说：“我们唯一要害怕的就是恐惧本身”时，

it was not a feel-good bromide, but a theorem of common knowledge.

这并不是一种让人感觉良好的情绪，而是常识性的定理。

With investors constantly on the lookout for focal points, financial leaders have to be wordsmiths, mystics and occasionally, comedians.

随着投资者不断寻找焦点，金融领袖必须成为文字大师、神秘主义者，有时甚至是喜剧演员。

Alan Greenspan once said, "Since I've become a central banker, I've learned to mumble with great incoherence."

艾伦·格林斯潘曾经说过：“自从我成为中央银行家以来，我学会了语无伦次。"

"If I seem unduly clear to you, you must have misunderstood what I said."

“如果我对你来说太清楚了，那么你一定误解了我所说的话。"

After Jimmy Carter told his inflation czar, Alfred Kahn, never to use the self-fulfilling word "depression,"

吉米·卡特告诉他的通货膨胀沙皇阿尔弗雷德·卡恩永远不要使用“抑郁症”这个自我实现的词后，

he said, "OK, but we're in danger of having the biggest banana in 45 years."

他说："好吧，但我们可能会面临45年来最严重的危机。"

Thank you.

谢谢。

本文来自公众微信号：听歌学英语