it's a feeling, and it's a reality.

安全有兩種涵義

And they're different.

感覺上的安全,和真實裡的安全

You could feel secure even if you're not.

二者並不相同

And you can be secure

你可能感到安全

even if you don't feel it.

但現實情況是不安全的

Really, we have two separate concepts

而在真實的安全中

mapped onto the same word.

卻感到不安全

And what I want to do in this talk is to split them apart --

確實,這兩種不同的概念

figuring out when they diverge and how they converge.

被放在同一個字詞裡

And language is actually a problem here.

這個演講的目的

There aren't a lot of good words

就是將它們區分清楚 --

for the concepts we're going to talk about.

探討它們何時會分歧

So if you look at security from economic terms,

又在什麼狀況下合而為一

it's a trade-off.

語言本身是個問題

Every time you get some security, you're always trading off something.

因為沒有足夠合適的字詞

Whether this is a personal decision --

來傳達我們要談到的概念

whether you're going to install a burglar alarm in your home --

用經濟學的角度

or a national decision,

來看安全

where you're going to invade a foreign country --

安全就是一項權衡的交易

you're going to trade off something: money or time, convenience, capabilities,

要得到安全

maybe fundamental liberties.

一定要先付出

And the question to ask when you look at a security anything

無論是個人的決定－

is not whether this makes us safer,

例如在家中安裝防盜警鈴

but whether it's worth the trade-off.

還是攸關國家安全的決策-例如侵略他國

You've heard in the past several years, the world is safer

你總得有所付出

because Saddam Hussein is not in power.

不是錢就是時間,或是便利性,能力

That might be true, but it's not terribly relevant.

也可能是基本自由

The question is: Was it worth it?

面對安全議題,該問的

And you can make your own decision,

不是「這樣做會更安全嗎」

and then you'll decide whether the invasion was worth it.

而是「值得付出這個代價嗎」

That's how you think about security: in terms of the trade-off.

在過去這幾年,你們都聽過這種說法

Now, there's often no right or wrong here.

我們的世界更安全是因為薩達姆.海珊垮台的緣故

Some of us have a burglar alarm system at home and some of us don't.

兩件事情也許都是真的，但兩者之間卻沒有關連

And it'll depend on where we live,

該問的問題是,這樣做值得嗎?

whether we live alone or have a family,

你可以做出自己的選擇

how much cool stuff we have,

然後判斷是否值得為此入侵他國

how much we're willing to accept the risk of theft.

這就是以權衡的觀點

In politics also, there are different opinions.

來分析安全的方法

A lot of times, these trade-offs are about more than just security,

決定沒有正確或錯誤之分

and I think that's really important.

有人在家裡安裝防盜警鈴系統

Now, people have a natural intuition about these trade-offs.

有人不裝

We make them every day.

這取決於我們居住的地點

Last night in my hotel room, when I decided to double-lock the door,

是獨居或是與家人同住

or you in your car when you drove here;

擁有多少值錢的物品

when we go eat lunch

以及願意承擔多少竊盜損失

and decide the food's not poison and we'll eat it.

竊盜損失

We make these trade-offs again and again,

政治上也一樣

multiple times a day.

各種意見分歧

We often won't even notice them.

在權衡得失時

They're just part of being alive; we all do it.

通常要考慮的不只有安全因素

Every species does it.

我認為這點很重要

Imagine a rabbit in a field, eating grass.

人們對於抉擇

And the rabbit sees a fox.

有天生的直覺

That rabbit will make a security trade-off:

我們每天都在做決定

"Should I stay, or should I flee?"

像是昨晚在飯店

And if you think about it,

我決定把房門上雙層鎖

the rabbits that are good at making that trade-off

或是當你在車裡決定開車來此地的時候

will tend to live and reproduce,

或是我們吃午餐時

and the rabbits that are bad at it

先判斷食物沒有毒,才決定吃它

will get eaten or starve.

一天中有很多場合需要

So you'd think

需要一再地做出決定

that us, as a successful species on the planet -- you, me, everybody --

大部分的時後,我們甚至不會留意到這點

would be really good at making these trade-offs.

因為這已是我們生存的一部份;我們都是這樣的

Yet it seems, again and again, that we're hopelessly bad at it.

每個物種也都一樣

And I think that's a fundamentally interesting question.

試想原野中的一隻兔子,正在吃著草

I'll give you the short answer.

這時牠見到一隻狐狸

The answer is, we respond to the feeling of security

兔子需要做一個攸關安全的抉擇

and not the reality.

留下還是逃命?

Now, most of the time, that works.

你認為

Most of the time,

擅長做出正確決定的兔子

feeling and reality are the same.

比較容易存活且繁衍下去

Certainly that's true for most of human prehistory.

而做出錯誤決定的兔子

We've developed this ability

不是被吃就是餓死了

because it makes evolutionary sense.

那麼

One way to think of it is that we're highly optimized

在地球上表現傑出優異的我們 --

for risk decisions

包括你、我、以及每個人 --

that are endemic to living in small family groups

必定也擅長做出正確抉擇吧

in the East African Highlands in 100,000 BC.

然而,事實似乎一再地證明

2010 New York, not so much.

人類做出的決策糟糕無比

Now, there are several biases in risk perception.

這問題非常重要也相當有趣

A lot of good experiments in this.

我給你們一個簡短的解答

And you can see certain biases that come up again and again.

答案是,因為人類是依據對安全的感覺做出判斷

I'll give you four.

而非依據真實的安全狀況

We tend to exaggerate spectacular and rare risks

大部分的情況下,這麼做是正確的

and downplay common risks --

因為大多數的時候

so, flying versus driving.

感覺和真實是一致的

The unknown is perceived to be riskier than the familiar.

人類在史前時代

One example would be:

也是這樣的

people fear kidnapping by strangers,

我們發展出這種能力

when the data supports that kidnapping by relatives is much more common.

是因演化而來

This is for children.

有些看法認為

Third, personified risks are perceived to be greater

人類目前所擁有的最佳能力

than anonymous risks.

是為了配合

So, Bin Laden is scarier because he has a name.

公元前100,000年在東非高地生活的小型家庭

And the fourth is:

他們生存所須具備的風險決策能力

people underestimate risks in situations they do control

但已不太符合在2010年的紐約生存的條件了

and overestimate them in situations they don't control.

如今,人類的風險感知能力出現偏差

So once you take up skydiving or smoking,

很多的實驗在探討這點

you downplay the risks.

某些類型的偏差會反覆出現

If a risk is thrust upon you -- terrorism is a good example --

我會說明其中的四種

you'll overplay it,

一,我們容易誇大驚心動魄且不常見的風險

because you don't feel like it's in your control.

卻低估常見的風險

There are a bunch of other of these cognitive biases,

例如搭飛機的風險對比陸地上駕駛的風險

that affect our risk decisions.

二,我們認為未知的事

There's the availability heuristic,

比起熟知的事更加危險

which basically means we estimate the probability of something

其中一個例子是

by how easy it is to bring instances of it to mind.

人們害怕被陌生人綁架

So you can imagine how that works.

但資料顯示被親友綁架的案件更普遍

If you hear a lot about tiger attacks, there must be a lot of tigers around.

這裡指的是誘拐孩童

You don't hear about lion attacks, there aren't a lot of lions around.

三,我們認為具名化的事件

This works, until you invent newspapers,

比不具名事件的風險高

because what newspapers do is repeat again and again

賓拉登很恐怖,正是因為他有個名字

rare risks.

第四

I tell people: if it's in the news, don't worry about it,

人們容易在可以控制狀況時

because by definition, news is something that almost never happens.

低估風險

(Laughter)

在不能控制的情境中高估風險

When something is so common, it's no longer news.

所以,你開始特技跳傘或是抽菸後

Car crashes, domestic violence --

就會忽略它的風險

those are the risks you worry about.

面對突如其來的危險-例如恐怖主義

We're also a species of storytellers.

人們會過度反應,是因為覺得無法控制狀況

We respond to stories more than data.

類似的偏差還有很多,這些認知的偏差

And there's some basic innumeracy going on.

影響我們的風險決策

I mean, the joke "One, two, three, many" is kind of right.

所謂”可得性捷思”

We're really good at small numbers.

指的是

One mango, two mangoes, three mangoes,

人在評估事件可能發生的機率時

10,000 mangoes, 100,000 mangoes --

是基於該事件在我們心目中容易聯想的程度

it's still more mangoes you can eat before they rot.

像一下這是怎麼運作的

So one half, one quarter, one fifth -- we're good at that.

聽到多起老虎攻擊事件,就表示附近老虎很多

One in a million, one in a billion --

沒聽到獅子攻擊事件,就表示附近的獅子不多

they're both almost never.

直到新聞報紙被發明前,這種判斷準則是成立的

So we have trouble with the risks that aren't very common.

因為報紙所做的

And what these cognitive biases do

就是一再地重複報導

is they act as filters between us and reality.

那些鮮少發生的危險

And the result is that feeling and reality get out of whack,

我要告訴大家,新聞中報導的事情,都無需煩憂

they get different.

因為根據定義

Now, you either have a feeling -- you feel more secure than you are,

新聞就是不會發生的事件

there's a false sense of security.

(笑)

Or the other way, and that's a false sense of insecurity.

太常見的事件,就不會是新聞

I write a lot about "security theater,"

像是車禍,家庭暴力

which are products that make people feel secure,

這些才是我們該擔憂的

but don't actually do anything.

人類是說故事的物種

There's no real word for stuff that makes us secure,

比起數據,故事更容易影響我們

but doesn't make us feel secure.

人類多少有點數字文盲,我的意思是

Maybe it's what the CIA is supposed to do for us.

有個笑話說:人只會數一,二,三,很多.

So back to economics.

人真的是這樣,我們對小數字很在行

If economics, if the market, drives security,

一個芒果,兩個芒果,三個芒果

and if people make trade-offs based on the feeling of security,

一萬個芒果,十萬的芒果

then the smart thing for companies to do for the economic incentives

在它們腐壞前,還有許多芒果可吃

is to make people feel secure.

½,¼, 1/5,這些數字我們也都很在行

And there are two ways to do this.

百萬分之一,十億分之一

One, you can make people actually secure

這些被當作幾乎沒有

and hope they notice.

所以,一旦面對不尋常的危機

Or two, you can make people just feel secure

我們就不知該怎麼對付了

and hope they don't notice.

認知的偏見

Right?

如同濾鏡般,存在我們和真實之間

So what makes people notice?

於是

Well, a couple of things:

感覺背離了真實

understanding of the security,

他們不再相同

of the risks, the threats,

並產生兩種可能狀況,一是擁有過多的安全感

the countermeasures, how they work.

這是錯誤的安全感

But if you know stuff, you're more likely

另一種是,

to have your feelings match reality.

錯誤的不安全感

Enough real-world examples helps.

我寫過很多關於「安全劇院」的文章

We all know the crime rate in our neighborhood,

它是一種可以讓人們感覺到安全的機制

because we live there, and we get a feeling about it

但事實上並沒有改善實際的安全狀況

that basically matches reality.

沒有確切的字眼來形容那種能改善真實安全

Security theater is exposed

但無法增加安全感的機制

when it's obvious that it's not working properly.

CIA該為我們做的也許就是這個

OK. So what makes people not notice?

回到經濟學

Well, a poor understanding.

如果經濟,或者市場,是驅動安全的力量

If you don't understand the risks, you don't understand the costs,

而人們是依據對安全的感覺

you're likely to get the trade-off wrong,

來進行交易

and your feeling doesn't match reality.

那麼,公司想要促進經濟誘因的

Not enough examples.

最佳策略

There's an inherent problem with low-probability events.

就是讓人們感覺到安全

If, for example, terrorism almost never happens,

有兩種方式可以達成這個目的

it's really hard to judge the efficacy of counter-terrorist measures.

一是讓人們在真實中更安全

This is why you keep sacrificing virgins,

並且期盼他們有留意到這點

and why your unicorn defenses are working just great.

或者你也可以讓人們只是感覺更安全

There aren't enough examples of failures.

但你要期望他們不會發現到真相

Also, feelings that cloud the issues --

究竟什麼會引起人們關注

the cognitive biases I talked about earlier: fears, folk beliefs --

舉例來說

basically, an inadequate model of reality.

對安全的認知程度

So let me complicate things.

對風險及威脅的認知

I have feeling and reality.

以及了解如何採取對策等

I want to add a third element. I want to add "model."

知道得更多

Feeling and model are in our head,

感覺和真實就愈趨一致

reality is the outside world; it doesn't change, it's real.

真實世界中有很多這方面的例子

Feeling is based on our intuition,

我們對居家附近區域的犯罪率很明瞭

model is based on reason.

因為我們住在這裡,所以我們對治安的感覺

That's basically the difference.

基本上符合真實狀況

In a primitive and simple world,

安全劇院所揭露的

there's really no reason for a model,

是真實與感覺明顯背離的情況

because feeling is close to reality.

那麼,又是什麼讓人們忽略安全?

You don't need a model.

認知不足

But in a modern and complex world,

不了解風險,不了解代價

you need models to understand a lot of the risks we face.

就愈可能做出錯誤的安全策略

There's no feeling about germs.

並且無法感覺真實情況

You need a model to understand them.

相關的例子不多

This model is an intelligent representation of reality.

對於不常發生的事件

It's, of course, limited by science, by technology.

這是本質上存在的問題

We couldn't have a germ theory of disease

舉例來說

before we invented the microscope to see them.

如果恐怖主義幾乎是不曾發生的

It's limited by our cognitive biases.

那麼要判斷反恐措施的功效

But it has the ability to override our feelings.

就難上加難了

Where do we get these models? We get them from others.

這就是為什麼人們不斷地奉獻處女祭祀

We get them from religion, from culture, teachers, elders.

或是將過錯推諉給編造出來的「他」,都很有用

A couple years ago, I was in South Africa on safari.

因為災難本來就不多

The tracker I was with grew up in Kruger National Park.

加上心理作用作祟

He had some very complex models of how to survive.

就是我剛剛所說的認知偏差

And it depended on if you were attacked by a lion, leopard, rhino, or elephant --

恐懼,民間信仰

and when you had to run away, when you couldn't run away,

這些基本上都無法適當地反映真實

when you had to climb a tree, when you could never climb a tree.

讓我把事情弄得再複雜些

I would have died in a day.

除了感覺,以及真實的世界

But he was born there, and he understood how to survive.

我想再加上第三個元素-模型

I was born in New York City.

感覺和模型存在腦海裡

I could have taken him to New York, and he would have died in a day.

而真實存在於外在

(Laughter)

它不會變,它是真實的

Because we had different models based on our different experiences.

感覺是基於直覺

Models can come from the media,

模型是基於理智

from our elected officials ...

這是兩者最基本的差異

Think of models of terrorism,

在遠古的簡單世界裡

child kidnapping,

模型沒有存在的意義

airline safety, car safety.

因為感覺和真實非常的接近

Models can come from industry.

你不需要模型

The two I'm following are surveillance cameras,

但在現代複雜的社會

ID cards,

你需要模型

quite a lot of our computer security models come from there.

來解析我們面對的風險

A lot of models come from science.

我們無法用感覺來認識細菌

Health models are a great example.

所以需要模型

Think of cancer, bird flu, swine flu, SARS.

模型可以

All of our feelings of security about those diseases

清楚地呈現真實

come from models given to us, really, by science filtered through the media.

然而,模型受限於科學

So models can change.

與技術

Models are not static.

在顯微鏡被發明來觀測細菌以前

As we become more comfortable in our environments,

疾病的細菌理論就不可能存在

our model can move closer to our feelings.