At what moment are you dead? - Randall Hayes

譯者: 陳 Chen 瑋佑 Wei Yu 審譯者: 瑞文Eleven 林Lim

For as far back as we can trace our existence,

自從人類存有以來

humans have been fascinated with death and resurrection.

人們就對死亡和復活的議題 充滿興趣

Nearly every religion in the world has some interpretation of them,

幾乎所有宗教 都有不同的生死觀

and from our earliest myths

從遠古神話到現代電影

to the latest cinematic blockbusters, the dead keep coming back.

死而復生總是最熱門的題材

But is resurrection really possible?

但「復活」這檔事真的存在嗎？

And what is the actual difference between a living creature and a dead body, anyway?

而活生生的生物和屍體 又有何實際差別？

To understand what death is, we need to understand what life is.

為了瞭解何謂「死」 我們得先探討何謂「生」

One ancient theory was an idea called vitalism,

有一個古老的理論 稱做「生機論」

which claimed that living things were unique

理論上，生物之所以有生命

because they were filled with a special substance, or energy,

是因為有種特殊物質或能量 存在於生物之中

that was the essence of life.

而這就是生命的本質所在

Whether it was called qi,

無論稱這種物質為「氣」

lifeblood,

「血」

or humors,

或是「體液」

the belief in such an essence was common throughout the world,

類似的想法相當普遍

and still persists in the stories of creatures

而且還是有人相信

有些生物能夠 吸取別人的「生命」

who can somehow drain life from others,

or some form of magical sources that can replenish it.

有些神秘物質 能夠使生命回春

Vitalism began to fade in the Western world

但西方在17世紀的科學革命之後

following the Scientific Revolution in the 17th century.

「生機論」開始逐漸式微

René Descartes advanced the notion

笛卡兒認為

that the human body was essentially no different from any other machine,

人體基本上跟機器沒有兩樣

brought to life by a divinely created soul located in the brain's pineal gland.

由神創造的靈魂 會被帶到腦的松果腺

And in 1907, Dr. Duncan McDougall even claimed that the soul had mass,

1907年麥克道格醫師 甚至認為靈魂有重量

weighing patients immediately before and after death in an attempt to prove it.

為了證明他的理論 他還測量人體在死亡前後的重量

Though his experiments were discredited, much like the rest of vitalism,

雖然世人認為他的實驗 如同生機論一樣，皆不足以採信

traces of his theory still come up in popular culture.

我們仍能在流行文化中 找到此論點的蹤跡

But where do all these discredited theories leave us?

但這些名譽掃地的理論 真的會被遺忘嗎?

What we now know is that life is not contained

我們現在知道的是

in some magical substance or spark,

生命不是被包含在一些神奇的物質或能量

but within the ongoing biological processes themselves.

不過生物本身正在進行的過程

And to understand these processes,

是我們需要瞭解的

we need to zoom down to the level of our individual cells.

我們需要放大到細胞等級來看

Inside each of these cells,

裡面每個細胞

chemical reactions are constantly occurring,

都不斷發生化學反應

powered by the glucose and oxygen that our bodies convert

由我們的身體轉化葡萄糖跟氧氣

into the energy-carrying molecule known as ATP.

成為攜帶能量的分子，也叫做ATP

Cells use this energy for everything from repair

全部的細胞都利用這種能量來

to growth

維修、增長

to reproduction.

繁殖等

Not only does it take a lot of energy to make the necessary molecules,

製造必要的分子需要消耗許多的能量

but it takes even more to get them where they need to be.

把這些分子送到需要的地方 還要消耗更多的能量

The universal phenomenon of entropy

這是熵的普遍現象

means that molecules will tend towards diffusing randomly,

這意味著分子將趨向於隨機擴散

moving from areas of high concentration to low concentration,

分子從高濃度的地方 移動到低濃度的地方

or even breaking apart into smaller molecules and atoms.

甚至會分崩離析成更小的分子或原子

So cells must constantly keep entropy in check

因此，細胞必須持續讓熵受到控制

by using energy to maintain their molecules

故耗費能量來維持他們的分子

in the very complicated formations

處於非常複雜的構造

necessary for biological functions to occur.

才能使生物功能得發揮

The breaking down of these arrangements when the entire cell succumbs to entropy

若整個細胞屈就於熵 這些機制開始瓦解

is what eventually results in death.

最後導致生物的死亡

This is the reason organisms can't be simply sparked back to life

這就是一旦生命體死亡

once they've already died.

就不能起死回生的理由

We can pump air into someone's lungs,

我們可以輸送氧氣進入生物的肺部

but it won't do much good

但如果呼吸系統的其他過程都失效了

if the many other processes involved in the respiratory cycle

注入再多空氣

are no longer functioning.

那也是無濟於事

Similarly, the electric shock from a defibrillator

同樣的，心臟電擊器的電擊

doesn't jump-start an inanimate heart,

無法重新啟動無生命的心

but resynchronizes the muscle cells in an abnormally beating heart

但可使心跳異常心臟的 心肌細胞重新同步

so they regain their normal rhythm.

恢復正常的節奏

This can prevent a person from dying, but it won't raise a dead body,

這可以拯救一個將死之人， 但它不能屍體復活

or a monster sewn together from dead bodies.

更不用說一個縫起來的怪物了

So it would seem that all our various medical miracles

所以，儘管我們有各種醫學奇蹟

can delay or prevent death but not reverse it.

雖然可以推遲或阻止死亡， 但不是能扭轉

But that's not as simple as it sounds

但也不能一概而論

because constant advancements in technology and medicine

因為醫學跟技術會不斷的進步

have resulted in diagnoses such as coma,

例如昏迷的病患

describing potentially reversible conditions,

有可能被救醒

under which people would have previously been considered dead.

在以前會以為好像沒救的情形

In the future, the point of no return may be pushed even further.

在將來，生命的盡頭 可能會變得更長

Some animals are known to extend their lifespans

我們知道有些動物會藉由

or survive extreme conditions

減緩生理機能甚至到停止

by slowing down their biological processes

來增長壽命或在惡劣環境下存活

to the point where they are virtually paused.

到了死前，牠們的生理機能幾乎暫停

And research into cryonics hopes to achieve the same

我們希望冷凍的研究 能達到相同的效果

by freezing dying people and reviving them later

凍結垂死的人

when newer technology is able to help them.

等有更新的科技能幫助他們時， 再將他們復活

See, if the cells are frozen, there's very little molecular movement,

看，如果細胞被凍住了 就只會進行非常細微的分子運動

and diffusion practically stops.

且擴散也已經幾乎停止了

Even if all of a person's cellular processes had already broken down,

即使一個人的細胞轉換過程已經壞了

this could still conceivably be reversed by a swarm of nanobots,

想像中仍然可以藉由一群 奈米機器人來反轉

moving all the molecules back to their proper positions,

將所有的分子放回 到其適當的位置

and injecting all of the cells with ATP at the same time,

也同時將ATP注射入細胞裡

presumably causing the body to simply pick up where it left off.

這也許可以讓生命體重新運作

So if we think of life not as some magical spark,

所以如果我們認為生命 不是某種神奇的火花

but a state of incredibly complex, self-perpetuating organization,

而是極其複雜的狀態下 自我延續的組織，

death is just the process of increasing entropy

死亡只是熵的過程

that destroys this fragile balance.

破壞了這個脆弱的平衡的過程

And the point at which someone is completely dead

一個人完全死亡的關鍵點

turns out not to be a fixed constant,

不再是一個固定的常數

but simply a matter of how much of this entropy

簡單來說就是目前我們能夠扭轉

we're currently capable of reversing.

多少熵的問題。