At what moment are you dead? - Randall Hayes

翻译人员: Melody Tang 校对人员: Sanqiang Xiao

For as far back as we can trace our existence,

从人类诞生开始，

humans have been fascinated with death and resurrection.

人类一直对死亡与复活着迷

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

几乎每个宗教都对它们有着不同的见解

and from our earliest myths

从早期的神话故事

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

到最新的电影大片中， 死者在不断的复活

But is resurrection really possible?

但是复活真的可能吗

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

生物的生与死的区别到底在哪里

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

要理解什么是死 我们必须先理解什么是生

One ancient theory was an idea called vitalism,

有一个被称为“活力论”的古老的理论

which claimed that living things were unique

它认为生物体是独特的

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

因为生物充满特别的物质或能量

that was the essence of life.

这种物质就是生物的本质

Whether it was called qi,

不管此物质被称之为气

lifeblood,

生命脉

or humors,

或是幽默

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

世界各地普遍深信这种物资的存在

and still persists in the stories of creatures

而且不时可以听到关于它们

who can somehow drain life from others,

可以从别的生物吸取生命的故事

or some form of magical sources that can replenish it.

或是某种神奇的原料可以补充它们

Vitalism began to fade in the Western world

在17世纪的科学革命后

following the Scientific Revolution in the 17th century.

“活力论”在西方世界开始失去市场

瑞内‧笛卡尔（René Descartes） 让这种理念更进一步

René Descartes advanced the notion

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

他主张人类的身体基本上 和任何机器并无两样

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

由位于脑内的松果体内的 神所创造的灵魂而有生命

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

在1907年当肯‧迈窦噶儿医生 甚至主张灵魂是有质量的

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

他以病人在死亡前后的所称的重量来证明

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

虽然他的实验，和其他活力理论一样， 没有被承认

traces of his theory still come up in popular culture.

我们仍能在流行文化中找到其理论的踪迹。

But where do all these discredited theories leave us?

除了这些不被接受的理论， 那我们还有什么其他的解释吗？

What we now know is that life is not contained

我们现在知道的是

生命不是被包覆在某种神奇的物资 或火花内

in some magical substance or spark,

but within the ongoing biological processes themselves.

而是不断的生物过程本身

要了解这些过程

And to understand these processes,

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

我们必须放大到我们的个体细胞上

Inside each of these cells,

在每一个细胞里

chemical reactions are constantly occurring,

化学反应不断地在发生

powered by the glucose and oxygen that our bodies convert

由我们身体转化葡萄糖和氧气

into the energy-carrying molecule known as ATP.

成为携带能量的分子，也叫ATP

细胞用这个能量来做修补，

Cells use this energy for everything from repair

成长，

to growth

to reproduction.

繁殖等

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

制造必须的分子需要消耗许多的能量

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

把这些分子送到需要的地方消耗更多的能量

The universal phenomenon of entropy

宇宙中的熵（entropy）现象

means that molecules will tend towards diffusing randomly,

表明分子有随机扩散的趋势

moving from areas of high concentration to low concentration,

它们会从分子集中的地方 扩散到分子少的地方

or even breaking apart into smaller molecules and atoms.

或者甚至分裂成更小的分子和原子

So cells must constantly keep entropy in check

所以细胞必须不断的保持着‘熵’

用能量来维持它们的分子们

by using energy to maintain their molecules

in the very complicated formations

以非常复杂的构造

necessary for biological functions to occur.

使生物功能得以发生

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

当细胞屈服于‘熵’，这些机制开始瓦解

is what eventually results in death.

最后导致生物体死亡

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

这也是一旦生命体死亡

once they've already died.

就不能起死回生的理由

We can pump air into someone's lungs,

我们可以将空气注入一个人的肺

但如果呼吸系统中的其他过程都失效了

but it won't do much good

if the many other processes involved in the respiratory cycle

注入再多的空气

are no longer functioning.

那也是无济于事

Similarly, the electric shock from a defibrillator

同样的，除顫器的电击

doesn't jump-start an inanimate heart,

也无法重启一个死亡的心脏

but resynchronizes the muscle cells in an abnormally beating heart

它只能使心跳异常的心脏 将肌肉细胞重新同步化

so they regain their normal rhythm.

让它恢复正常的律动

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

这是可以防止一个人的死亡， 但它不会使人起死回生

or a monster sewn together from dead bodies.

更不用说由死尸缝起来的怪物

So it would seem that all our various medical miracles

所以尽管我们有各种医学奇迹

can delay or prevent death but not reverse it.

可以延迟或预防死亡 但不能转死为生

但也不能一概而论

But that's not as simple as it sounds

because constant advancements in technology and medicine

因为科技和医药的不断进步

have resulted in diagnoses such as coma,

可将如昏迷的诊断 为有反转的可能性

describing potentially reversible conditions,

under which people would have previously been considered dead.

这些在以前人们会认为已经死亡了

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

在未来，回生乏力的关键点 可能可再向后推

Some animals are known to extend their lifespans

据我们所知，有些动物可以借由

放慢他们的生物过程，甚至到停止作用

or survive extreme conditions

by slowing down their biological processes

而增长寿命或在极为恶劣的情况下存活

to the point where they are virtually paused.

And research into cryonics hopes to achieve the same

人体冷冻学的研究就是 希望可以达到这个结果

by freezing dying people and reviving them later

借由将濒死者冷冻

当更新的科技可以帮助他们的时候 再将他们复活

when newer technology is able to help them.

比如说，当细胞冷冻以后， 就几乎没有分子活动

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

and diffusion practically stops.

扩散也基本停止了

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

即便一个人的细胞流程已经瓦解了

想象中仍然可以借由一群 納米机器人而反转的

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

moving all the molecules back to their proper positions,

将所有分子放回它们的适当位置

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

也同时将ATP注射在细胞里

这也许可以让生命体可以重新运作

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

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

所以如果我们认为生命不是 某种神奇的火花

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

而是一种无法想象的复杂， 和自我延续的组织的状态

death is just the process of increasing entropy

死亡只是熵增过程，

that destroys this fragile balance.

破坏了这个脆弱的平衡的过程

And the point at which someone is completely dead

当一个人完全死亡的关键点

turns out not to be a fixed constant,

不再是一个固定常数

but simply a matter of how much of this entropy

而是由我们现在能够逆转这个‘熵’的程度

we're currently capable of reversing.

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［你在哪个时刻死亡？］