you encounter something

身為一個研究人員，

a little disconcerting.

每過一陣子，總是會遇到

And this is something that changes your understanding of the world around you,

一些令人驚訝的事，

and teaches you that you're very wrong

這些事會改變你對週遭世界的認知，

about something that you really believed firmly in.

讓你瞭解你以往所深信的某些事，

And these are unfortunate moments,

其實是大錯特錯。

because you go to sleep that night

我認為遇到這種事其實不好過，

dumber than when you woke up.

因為你會覺得自己

So, that's really the goal of my talk,

比前一天又笨了一點。

is to A, communicate that moment to you

這就是我今天演說的目的，

and B, have you leave this session

第一，和你們談談那些不好過的經驗，

a little dumber than when you entered.

第二，希望你們在離開會場時，

So, I hope I can really accomplish that.

會變得比之前更笨一點。

So, this incident that I'm going to describe

我希望我能達成這二個目標。

really began with some diarrhea.

我要談的這件事，

Now, we've known for a long time the cause of diarrhea.

其實可以從痢疾談起。

That's why there's a glass of water up there.

我們早就知道痢疾是怎麼引起的，

For us, it's a problem, the people in this room.

所以我放了一張一杯水的投影片在上面。

For babies, it's deadly.

對我們在座的各位來說，那不就只是個健康問題而已，

They lack nutrients, and diarrhea dehydrates them.

但是對小嬰兒來說，卻有可能致命，

And so, as a result, there is a lot of death,

因為他們吸收不到養份，痢疾還會使他們脫水，

a lot of death.

因此造成了極高的死亡率，

In India in 1960,

很多嬰兒死亡。

there was a 24 percent child mortality rate,

在1960代的印度，

lots of people didn't make it. This is incredibly unfortunate.

孩童的死亡率是24%，

One of the big reasons this happened was

很多小孩熬不過去，真的很不幸！

because of diarrhea.

死亡率居高不下的主要原因，

Now, there was a big effort to solve this problem,

就是痢疾。

and there was actually a big solution.

現在，有很多人致力於改善這個問題，

This solution has been called, by some,

也有很有效的解決方法，

"potentially the most important medical

有人稱這個方法為：

advance this century."

「有可能是本世紀最重要的

Now, the solution turned out to be simple.

醫學突破」。

And what it was was oral rehydration salts.

這個方法出奇地簡單，

Many of you have probably used this.

就是使用口服補液鹽，

It's brilliant. It's a way to get sodium

在座各位可能有使用過，

and glucose together so that when you add it to water

那真是一個好方法！裡面混合了

the child is able to absorb it even during situations of diarrhea.

鈉與葡萄糖，所以當我們摻入水中，

Remarkable impact on mortality.

孩子們即使感染了痢疾，還是能夠吸收到這些養份。

Massive solution to the problem.

這大幅降低了孩童死亡率，

Flash forward: 1960, 24 percent child mortality

並大幅改善了這個問題。

has dropped to 6.5 percent today.

讓我們看看，1960年代有24%的孩童死亡率，

Still a big number, but a big drop.

現在已經降到了6.5%了，

It looks like the technological problem is solved.

雖然比率還是很高，但已經下降了許多。

But if you look, even today

看起來這個問題的技術面已經克服了，

there are about 400,000 diarrhea-related deaths

但是，如果我們看看今天的狀況，

in India alone.

在印度，仍然有40萬人死於

What's going on here?

痢疾相關的疾病，

Well the easy answer is, we just haven't gotten those salts

究竟是怎麼回事？

to those people.

不用想也知道，就是我們沒有提供那些鹽

That's actually not true.

給需要的人啊...

If you look in areas where these salts are completely available,

這個想法不對，

the price is low or zero, these deaths still continue abated.

如果你仔細觀察，你會發現這種鹽到處都買得到，

Maybe there's a biological answer.

價格也很低，甚至不用錢，但是死亡率還是很高。

Maybe these are the deaths that simple rehydration

或許是生物學上的問題吧？

alone doesn't solve. That's not true either.

或許他們純粹是因為脫水

Many of these deaths were completely preventable,

而沒有辦法醫治好？這也不對。

and this what I want to think of as the disconcerting thing,

大部分痢疾患者的死亡都是可以避免的，

what I want to call "the last mile" problem.

這就是我所說的令人驚訝的事，

See, we spent a lot of energy, in many domains --

也就是我稱之為「最後一哩」的問題。

technological, scientific, hard work,

我們在不同的領域裡都投注了相當多的精力，

creativity, human ingenuity --

不管是科技、科學、勞動、

to crack important social problems with technology solutions.

創造或工藝等，

That's been the discoveries of the last 2,000 years,

我們都運用了科技來解決這些重要的社會問題。

that's mankind moving forward.

我們近二千年來都是這麼做，

But in this case we cracked it,

是人性推動著我們往前邁進。

but a big part of the problem still remains.

但我們在處理痢疾這個問題時，

Nine hundred and ninety-nine miles went well,

卻仍有一大部分的問題沒有解決；

the last mile's proving incredibly stubborn.

前面那999哩路我們都走得很順暢，

Now, that's for oral rehydration therapy.

但最後那一哩路卻顯得異常艱難。

Maybe this is something unique about diarrhea.

我們運用口服補液療法來治療痢疾，

Well, it turns out -- and this is where things get really disconcerting --

但或許這種痢疾特別難治，

it's not unique to diarrhea.

可是我們發現了驚人的事實，

It's not even unique to poor people in India.

這種痢疾並不算特別，

Here's an example from a variety of contexts.

在印度的窮人間算是很普遍的。

I've put a bunch of examples up here.

我要舉一個綜合了多種元素的例子，

I'll start with insulin, diabetes

我會把各種例子都放在上面，

medication in the U.S.

就先從美國治療

OK, the American population.

糖尿病的胰島素開始談起吧。

On Medicaid -- if you're fairly poor you get Medicaid,

好，先談美國的人口結構，

or if you have health insurance -- insulin is pretty straightforward.

如果你是個很窮的美國人，你可以靠醫療補助取得胰島素，

You get it, either in pill form or you get it as an injection;

或如果你有醫療保險的話，你也可以輕易得到胰島素治療，

you have to take it every day to maintain your blood sugar levels.

不管是服用胰島素藥劑或是針劑注射都可以，

Massive technological advance:

你必須每天服用或注射，以維持血糖的水準。

took an incredibly deadly disease, made it solvable.

我們在這上面運用了大量先進的科技，

Adherence rates. How many people are taking their insulin every day?

讓這種致死率極高的病症獲得控制。

About on average, a typical person is taking it 75 percent of the time.

我們來看看持續率，有多少人每天都服用或注射胰島素？

As a result, 25,000 people a year go blind,

平均來說，每個人大約都只有75%的時間會依照指示用藥，

hundreds of thousands lose limbs, every year,

因此，每年都有2萬5千人因此而失明，

for something that's solvable.

每年都有數十萬人因此截肢，

Here I have a bunch of other examples,

糖尿病並非無藥可醫啊...

all suffer from the last mile problem.

我還有一大堆這種例子，

It's not just medicine.

都是無法堅持到最後一哩才產生問題，

Here's another example from technology:

不只是醫療方面的問題，

agriculture. We think

這裡還有其他科技上的問題，

there's a food problem, so we create new seeds.

像是農業。

We think there's an income problem, so we create

我們以為會有糧食危機，所以我們製造出新品種的種子；

new ways of farming that increase income.

我們以為農人的收入會是問題，

Well, look at some old ways, some ways that we'd already cracked.

所以我們開發新的農耕技術以提升收入。

Intercropping. Intercropping really increases income.

嗯，我們來看看以前的老方法，那些我們已經實行多年的老方法，

Sometimes in rice we found incredible increases in yield

例如交叉耕作。交叉耕作確實能增加農民的收入，

when you mix different varieties of rice side by side.

在耕作稻米時，有時我們會發現，當你將不同品種的稻米

Some people are doing that,

一排一排地交叉耕作時，其產量會出奇地高。

many are not. What's going on?

有些人會這樣做，

This is the last mile.

但大部分的人不採用這種方法，為什麼？

The last mile is, everywhere, problematic.

這就是最後一哩的問題，

Alright, what's the problem?

每一個例子的問題都出在最後一哩，

The problem is this little three-pound machine

那麼，究竟最後一哩的問題是什麼？

that's behind your eyes and between your ears.

問題出在這個重約1.5公斤、

This machine is really strange,

躲在你眼睛後面、夾在你耳朵中間的玩意兒，

and one of the consequences is that people are weird.

這玩意兒真的很奇怪，

They do lots of inconsistent things.

所以讓人們的行為也變得很怪異，

(Applause)

人們會做出一堆前後不一致的事情出來！

They do lots of inconsistent things.

(掌聲)

And the inconsistencies

人們就是會做一堆前後不一致的事情！

create, fundamentally, this last mile problem.

就是這種不一致，

See, when we were dealing with our biology, bacteria,

才製造出我們剛才所談的最後一哩的問題。

the genes, the things inside here, the blood?

看看，在我們研究生物學、細菌、

That's complex, but it's manageable.

基因、這裡面的東西、血液等，

When we're dealing with people like this?

看似很複雜，但我們都還能處理；

The mind is more complex.

但是當我們處理這一類人的問題時，

That's not as manageable, and that's what we're struggling with.

人的心智又更複雜，

Let me go back to diarrhea for a second.

並不像先前那些東西容易應付，那就是我們陷入的困境。

Here's a question that was asked in the National Sample Survey,

我想先回來談一下痢疾，

which is a survey asked of many Indian women:

國家抽樣調查協會在一項針對印度婦女的調查中，

"Your child has diarrhea.

曾問過這樣一個問題，

Should you increase, maintain or decrease the number of fluids?"

「如果你的孩子得了痢疾，

Just so you don't embarrass yourselves, I'll give you the right answer:

你該增加／不變／減少孩子攝取的水份量？」

It's increase.

為了不讓各位難堪，我就直接把答案公布出來，

Now, diarrhea's interesting

答案是增加。

because it's been around for thousands of years,

痢疾很有趣，

ever since humankind really

它已經存在了幾千年了，

lived side by side enough to have really polluted water.

自從人類開始群居在一起，

One Roman strategy that was very interesting

群居的密度大到足以污染水源時就開始存在。

was that -- and it really gave them a comparative advantage --

羅馬人對付痢疾很有一套，

they made sure their soldiers didn't drink

這讓羅馬人佔盡了優勢，

even remotely muddied waters.

他們要求士兵不得飲用髒污的水，

Because if some of your troops get diarrhea they're not that effective

即使在很遠以外的污水也不可以。

on the battlefield.

因為士兵一旦染上了痢疾，就無法在戰場上

So, if you think of Roman comparative advantage part of it was the breast shields,

發揮戰鬥力。

the breastplates, but part of it was drinking the right water.

如果你以為羅馬人的優勢是在於他們的盾牌，

So, here are these women. They've seen their parents

在於他們的盔甲，那麼另一個優勢就是他們知道要飲用乾淨的水。

have struggled with diarrhea, they've struggled with diarrhea,

好，這些印度婦女早就看過他們的父母

they've seen lots of deaths. How do they answer this question?

與痢疾纏鬥，他們自己也與痢疾纏鬥過，

In India, 35 to 50 percent say "Reduce."

他們看過無數人死去，那麼他們的答案是什麼呢？

Think about what that means for a second.

有35%到50%的印度婦女的答案是「減少」。

Thirty-five to 50 percent of women

請你花點時間好好想想這代表了什麼意思，

forget oral rehydration therapy,

有35%到50%的印度婦女

they are increasing --

忘記了有口服補液療法，

they are actually making their child

他們反而加速...

more likely to die through their actions.

他們所採取的行動，反而讓

How is that possible?

孩子們加速死去，

Well, one possibility -- I think that's how most people respond to this --

為什麼會這樣？

is to say, "That's just stupid."

嗯，我認為大部份的人會想：

I don't think that's stupid.

「因為他們愚昧無知。」

I think there is something very profoundly right in what these women are doing.

我不覺得他們愚昧無知，

And that is, you don't put water

我反而認為這些婦女所做的事，一定有非常正確的理由，

into a leaky bucket.

也就是：你不會把水倒進

So, think of the mental model that goes behind reducing the intake.

會漏水的桶子裡吧...

Just doesn't make sense.

想想看他們減少孩子的水份攝取量背後所持的理由，

Now, the model is intuitively right.

儘管不合理，

It just doesn't happen to be right about the world.

但在直覺上來說卻是沒有問題的，

But it makes a whole lot of sense at some deep level.

只是世界上其他的人並不這麼想，

And that, to me, is the fundamental challenge

但你只要再深入想想你就會瞭解他們的想法。

of the last mile.

這對我來說，就是最後一哩背後

This first challenge is what I refer to as the persuasion challenge.

所代表的艱鉅挑戰。

Convincing people to do something --

第一個挑戰，我稱之為說服的挑戰。

take oral rehydration therapy, intercrop, whatever it might be --

要說服別人做一件事，

is not an act of information:

像是採用口服補液療法、交叉耕作等等，

"Let's give them the data,

都不只是告訴他們有這件事而已。

and when they have data they'll do the right thing."

「我們來把資料發送出去，

It's more complex than that.

他們拿到資料就會開始做正確的事了。」

And if you want to understand how it's more complex

沒有這麼簡單。

let me start with something kind of interesting.

如果你想要知道為什麼沒有這麼簡單，

I'm going to give you a little math problem,

就讓我用一些有趣的例子來說明吧。

and I want you to just yell out the answer as fast as possible.

我先給你們做一些小小的數學測驗，

A bat and a ball together cost $1.10.

我要你們儘快地將答案大聲說出來。

The bat costs a dollar more than the ball.

一支球棒和一顆球加起來是1.1美元，

How much does the ball cost? Quick.

球棒比球貴1元，

So, somebody out there says, "Five."

請問球是多少錢？快點答！

A lot of you said, "Ten."

那邊有人說5美分，

Let's think about 10 for a second.

大部分的人說10美分，

If the ball costs 10, the bat costs...

我們先來想想10美分這個答案，

this is easy, $1.10.

如果球是10美分，那球棒是...

Yeah. So, together they would cost $1.20.

這很簡單嘛...1.1元

So, here you all are, ostensibly educated people.

對吧？所以加起來就是1.2美元。

Most of you look smart.

在座各位很明顯都是受過教育的人，

The combination of that produces

大部分的人都很聰明，

something that is actually, you got this thing wrong.

受過教育又聰明的人

How is that possible? Let's go to something else.

卻做出這個錯誤的答案，

I know algebra can be complicated.

怎麼會這樣？我們來看看其他的問題，

So, let's dial this back. That's what? Fifth grade? Fourth grade?

我覺得代數太複雜了，

Let's go back to kindergarten. OK?

我們往回推一點好了，那要回推到哪裡呢？五年級？還是四年級？

There's a great show on American television that you have to watch.

要不乾脆回推到幼稚園好了？

It's called "Are You Smarter Than a Fifth Grader?"

美國有一個很棒的電視節目，你一定得看，

I think we've learned the answer to that here.

節目叫做「你比五年級生聰明嗎？」，

Let's move to kindergarten. Let's see if we can beat five-year-olds.

我們剛剛才證明了你們是不是比五年級生聰明。

Here's what I'm going to do: I'm going to put objects on the screen.

那麼我們考些幼稚園的問題好了，看看你們是否能打敗五歲的小孩。

I just want you to name the color of the object.

我要做的是，把幾個圖案放在投影片上，

That's all it is. OK?

我要請你們把圖案的顏色說出來，

I want you to do it fast, and say it out loud with me,

這樣就好了，可以嗎？

and do it quickly. I'll make the first one easy for you.

我要你們很快地說出顏色，和我一起大聲地說出來，

Ready? Black.

而且要很快。第一個先來個簡單的，

Now the next ones I want you to do quickly and say it out loud.

準備好了嗎？黑色。

Ready? Go.

接下來，我要你們很快地大聲說出顏色，

Audience: Red. Green.

可以嗎？開始！

Yellow. Blue. Red.

觀眾：紅色、綠色、

(Laughter)

黃色、藍色、紅色。

Sendhil Mullainathan: That's pretty good.

(笑聲)

Almost out of kindergarten.

山迪：很好！

What is all this telling us?

幾乎比幼稚園小朋友還要好了！

You see, what's going on here, and in the bat and ball problem

這件事有什麼意義？

is that you have some intuitive ways of interacting with the world,

你們剛才的表現，和剛才回答球棒與球的問題，

some models that you use to understand the world.

你們都是用直覺來回應這個世界的問題，

These models, like the leaky bucket,

你所使用的是你以往所瞭解的模式，

work well in most situations.

這些模式就像印度婦女所想到的漏水的桶子，

I suspect most of you --

在大部分狀況下都可以應付一般的問題。

I hope that's true for the rest of you --

我相信大部分的人...

actually do pretty well with addition and subtraction in the real world.

希望其他的人也是一樣，

I found a problem, a specific problem

在現實生活裡應該都能做出正確的加法與減法。

that actually found an error with that.

但我發現了一個特別的問題，

Diarrhea, and many last mile problems, are like that.

會讓我們犯下錯誤，

They are situations where the mental model

也就是我們在痢疾和其他最後一哩的問題上所犯的錯誤。

doesn't match the reality.

我發現，有時候我們的直覺反應

Same thing here:

與現實世界並不相符。

You had an intuitive response to this that was very quick.

剛才也是一樣，

You read "blue" and you wanted to say "blue," even though you knew your task was red.

你們的直覺反應非常迅速，

Now, I do this stuff because it's fun.

你看到了用紅色所書寫的「blue(藍色)」，你沒有說出紅色，卻說成了藍色。

But it's more profound than fun.

我這麼做純粹只是逗你們玩，

I'll give you a good example of how it actually effects persuasion.

但其背後的意義卻不只好玩而已。

BMW is a pretty safe car.

我來舉一個例子，讓你們瞭解說服的影響力。

And they are trying to figure out, "Safety is good.

BMW是很安全的車子，

I want to advertise safety. How am I going to advertise safety?"

他們想要瞭解：「我們的安全性很好啊...

"I could give people numbers. We do well on crash tests."

希望大家都能知道我們的安全性，要怎麼在廣告上呈現安全性呢？」

But the truth of the matter is, you look at that car,

「我們就把數據呈現出來吧！我們在撞擊測試中表現得很好！」

it doesn't look like a Volvo,

但事實上，當你看著那台車，

and it doesn't look like a Hummer.

它就不像Volvo那麼堅固，

So, what I want you to think about for a few minutes