Can you outsmart the fallacy that fooled a generation of doctors? - Elizabeth Cox

譯者: Lilian Chiu 審譯者: Pui-Ching Siu

Oh the humanity!

喔，人類！

Ah... humanity...

啊……人類……

It’s a trainwreck, but I can’t look away.

這是場災難，但我無法不去看。

It’s 1843, and a debate is raging among physicians

現在是 1843 年，物理學家之間 有一場辯論越演越烈，

about one of the most common killers of women: childbed fever.

主題是女性最常見的 死因之一：產褥熱。

Childbed fever strikes within days of giving birth,

女性在產後幾天內就會得到產褥熱，

killing more than 70% of those infected— and nobody knows what causes it.

受感染的人當中有超過 70% 會死亡，

沒有人知道成因。

Obstetrician Charles Meigs has a theory.

產科醫生查爾斯·梅格斯有個理論。

Having observed abdominal inflammation

他曾經觀察到腹部發炎的病人

in patients who go on to develop the fever,

後來發展出產褥熱，

he claims this inflammation is the cause of childbed fever.

因此聲稱這種發炎 就是產褥熱的成因。

Much of the medical establishment supports his theory.

大部分的醫學機構都支持他的理論。

Oh, come on!

喔，拜託！

They really leave me no choice but to teach them some skepticism.

他們真的讓我別無選擇， 我只好教教他們什麼是懷疑的態度。

That’s better.

這樣好多了。

Now, Meigs, your argument is based on a fallacy— the false cause fallacy.

梅格斯，你的主張其實 立基在一個謬誤上——

因果謬誤。

Correlation does not imply causation:

有相關性不表示有因果關係。

When two phenomena regularly occur together,

當兩種現象經常一起發生時，

one does not necessarily cause the other.

其中一種不見得就是另一種的成因。

So you say women who have inflammation also come down with childbed fever,

你說有發炎現象的女性

也會染上產褥熱，

therefore the inflammation caused the fever.

因此發炎就會造成產褥熱。

But that’s not necessarily true.

但那不見得是對的。

Yes, yes, the inflammation comes first, then the fever,

是，是，發炎先發生， 接著才有產褥熱，

so it seems like the inflammation causes the fever.

所以看似是發炎造成了產褥熱。

But by that logic, since babies usually grow hair before teeth,

但若依照這種邏輯，

因為嬰兒通常是 先長出頭髮才長出牙齒，

hair growth must cause tooth growth.

長頭髮就一定是長牙齒的成因。

And we all know that’s not true, right?

我們都知道不是這樣，對吧？

Actually, don’t answer that.

還是別回答好了。

A couple of different things could be going on here.

在這個例子中， 可能的狀況有好幾個。

First, it’s possible that fever and inflammation are correlated

第一，產褥熱和發炎會有相關性

purely by coincidence.

有可能純粹是巧合。

Or, there could be a causal relationship that’s the opposite of what you think—

或者，它們之間可能有因果關係，

但方向和你想的完全相反——

the fever causes the inflammation,

產褥熱造成了發炎，

rather than the inflammation causing the fever.

而不是發炎造成了產褥熱。

Or both could share a common underlying cause you haven’t thought of.

或者，

兩者可能都是由一個 你還沒想到的背後成因造成的。

If I may, just what do you think causes inflammation? Nothing?

容我這麼問，你認為是什麼

造成發炎的？沒有原因？

It just is? Really?

就是發炎了？真的？

Humor me for a moment in discussing one of your colleague’s ideas—

配合我一下，我們來討論 你同事提出的一個想法——

Dr. Oliver Wendell Holmes.

奧利弗·溫德爾·霍姆斯醫生。

I know, I know, you don’t like his theory—

我知道，我知道， 你不喜歡他的理論——

you already wrote a scathing letter about it.

你已經為此寫了一封尖刻的信。

But let’s fill your students in, shall we?

但咱們就姑且滿足 你的學生一下，好嗎？

Holmes noticed a pattern: when a patient dies of childbed fever,

霍姆斯注意到一種模式：

當病人死於產褥熱，

a doctor performs an autopsy.

醫生會進行解剖。

If the doctor then treats a new patient,

如果這位醫生接著 去治療一位新的病人，

that patient often comes down with the fever.

那位病人通常也會染上產褥熱。

Based on this correlation

根據這種解剖產褥熱病人

between autopsies of fever victims and new fever patients,

與新產褥熱病人之間的關聯性，

he proposes a possible cause.

他提出了一個可能的成因。

Since there’s no evidence that the autopsy causes the fever beyond this correlation,

因為除了這種關聯之外，

沒有證據顯示解剖會造成產褥熱，

he doesn’t jump to the conclusion that autopsy causes fever.

所以他沒有馬上下結論 認定解剖會造成產褥熱。

Instead, he suggests that doctors are infecting their patients

反之，

他提出醫生會透過 自己手上和手術器具上

via an invisible contaminant on their hands and surgical instruments.

那些看不見的感染源 而感染他們的病人。

This idea outrages most doctors, who see themselves as infallible.

這個想法冒犯了大部分的醫生，

他們都認為自己永無過失。

Like Meigs here, who refuses to consider the possibility

梅格斯也一樣，他拒絕去思考

that he’s playing a role in his patients’ plight.

自己有可能在病人的困境中 也有擔當一個角色。

His flawed argument doesn’t leave any path forward for further investigation—

他這個有瑕疵的主張沒有留下 任何空間供進一步的探究——

but Holmes’ does.

但霍姆斯的主張卻有。

It’s 1847, and physician Ignaz Semmelweis

現在是 1847 年， 伊格納茲·塞麥爾維斯醫生

has reduced the number of childbed fever deaths

將一間診所中的產褥熱死亡率

in a clinic from 12% to 1% by requiring all medical personnel

從 12% 減低到 1%，

他的做法是要求所有醫療人員

to disinfect their hands after autopsies and between patient examinations.

在解剖後及不同病人的檢查之間 都要做好雙手消毒。

With this initiative, he has proven the contagious nature of childbed fever.

他用這個做法證明了 產褥熱傳染性的本質。

Ha!

哈！

It’s 1879, and Louis Pasteur has identified

現在是 1879 年， 路易·巴斯德找出了

the contaminant responsible for many cases of childbed fever:

造成許多產褥熱案例的感染源：

Hemolytic streptococcus bacteria.

溶血性鏈球菌。

Hmm, my fries are cold.

嗯，我的薯條冷掉了。

Must be because my ice cream melted.

那一定是因為我的冰淇淋融化了。