From a scientist's prospective it's going to be rather different from that of most religious traditions,

从科学家的角度来看 这与传统的宗教思想大相径庭

which holds that we die because this is only a temporary staging area before we go to the big show

宗教思想认为我们之所以会死 是因为死亡只是我们进入下一个重要阶段的短暂状态

the next stage in which we go to heaven or hell or wherever some kind of afterlife.

下一个阶段是指我们会升入天堂或被打入地狱 亦或是某种来世

For scientists the question has a rather different answer and it has to do with the kinds of causes we look for in science.

科学家认为这个问题有另一种答案 它与我们在科学上所寻求的原因有关

So you have proximate causes versus ultimate causes.

有直接原因和最终原因两种

For example, why does sugar taste sweet or why does fruit taste sweet something like that?

比如 为什么糖是甜的 或为什么水果会是甜的

You would say well because there's molecular receptors on your tongue

你可能会说 是因为水果会让你舌头上的分子神经末梢

that are geared toward sending signals to a certain part of the brain

向大脑的某一部位发送信号

that register sweetness and pleasure and so on with fruit.

传达出甜和愉悦感

That's approximate answer.

那只是一种近似的答案

And ultimate answer is because foods that taste sweet are more likely to be consumed

而最终答案是 因为甜的食物更容易被消化吸收

and those in our natural environment are the kinds of foods that are both rare and nutritious

而自然环境中的甜食都是既稀有又富含营养

and so the more of them you eat the better and we evolved that tendency.

所以你吃的越多越好 于是我们便进化出了这种癖好

To answer the question why we die, it's the same kind of thing.

要回答我们为什么会死这个问题 是一样的道理

Approximate answers include cancer, heart disease, arthrosclerosis.

近似的答案包括癌症 心脏病 关节硬化

The ultimate answer though is found in two principles of nature,

但最终答案却隐藏在自然界的两条法则中

that is the second law of thermodynamics or entropy,

那就是热力学第二定律或熵

which means everything runs down, including our bodies.

它意味着万物都是向下传递的 包括我们的身体

And the whole universe, the whole universe runs down

整个宇宙 全宇宙都会向下传递

so ultimately even if you could double your lifespan, triple it,

所以最终即便你能够将寿命翻两倍 翻三倍

live essentially forever you can't really because the universe will eventually die in a heat death.

你依然无法真正做到永生 因为宇宙最终也会因为热寂而消亡

And then second is the principle of natural selection that drives evolution.

第二条法则就是推动进化的自然选择

And it has to do with a cost benefit analysis of how many limited resources you put into organisms.

它与你在生物体上投入了多少有限资源的成本效益分析有关

So obviously natural selection is going to select for infants and toddlers and babies to be well cared for,

很明显 自然选择会让婴儿和孩童得到精心的呵护

have super regenerative powers to keep their bodies going

让他们拥有超级再生力量 维持机体运转

in order to get the genes into the next generation,

以便把基因传递给下一代

get them up to reproductive age and so on.

把下一代养育至生育年龄等等

So we see cells that divide very rapidly in infants and babies.

所以婴儿和孩童的细胞分化非常快

A little cut you could practically watch it heal. It's incredible.

你甚至能看到他们身上的小伤口在自动愈合 非常难以置信

Whereas someone my age when I get cut it takes much longer to heal.

但像我这个年龄的人 如果受伤了 需要很久才能愈合

And so the question is why wouldn't evolution just make it so that I,

所以问题是 为什么进化不让我这种

now in my early 60s, can't just keep going to 200/300?

六十出头的人也拥有这种能力 好活到两三百岁呢？

And the answer is there's no reason for it.

答案是它没有理由这么做

Because after I've brought my own offspring into reproductive age

因为在我把自己的孩子抚养至生育年龄后

and then they've brought their offspring into reproductive age I'm really of no use anymore.

他们也把他们的子女养到了生育年龄 我就没有任何价值了

I can serve a useful purpose as a parent, of course, bringing my genes up

作为父母 我自然是有价值的 把子女抚养成人

and then useful purpose as a grandparent to help my offspring bring their offspring up to reproductive age,

作为祖父母 我也是有价值的 帮助我的子女把他们的孩子养至生育年龄

but beyond that really there's no sense in pouring any more resources into great, great, great, great, great grandparents

但除此之外 大自然没有必要在曾曾曾曾曾祖父母身上投入更多资源

because the genes in the little infant are already going to be well taken care of.

因为新生婴幼儿身上的基因早就已经得到了良好的照顾

So it's sort of a weird way to think about it, but in a way nature operates because of entropy.

这么想可能有点怪 但在某种程度上 自然是根据熵来运作的

Nature has to select and choose in kind of a triage where are we going to put the resources.

大自然必须要挑选并选择把资源投放在哪些东西上

I'm saying it like there's somebody up there allocating resources,

我说得好像有某种超越人类的力量在分配资源一样

the government is doling out checks to organisms.

有某种政府在向生物体发放支票

No, there is nothing like that, of course, this is just how natural selection operates.

不是的 当然不存在那种东西 这只是自然选择的运作方式

So in short, we die so that our future generations may live because there are limited resources.

所以简而言之 我们的死亡是为了让后代得以存活 毕竟资源有限