In movies, kings are always searching for the secret to immortality.

電影中，國王總是在尋找長生不老的秘密

But is immortality really a good thing?

但長生不老真是一件好事嗎？

To a ten year old boy, one year is the same as 10% of his life.

對一個十歲男孩來說，一年就相當於他生命的百分之十

To his forty year old mother, one year is merely 2.5% of her life.

對他四十歲的母親而言，一年僅僅只是生命的百分之 2.5

The same year, 365 days, can feel differently to different people.

同樣的一年， 365 天，對不同的人來說體驗也不同

If we live until we're 82, that's about 30,000 days.

如果我們活到 82 歲，那就是大約三萬個日子

If this boy lives for 30,000 years, a year to him could feel like a day.

如果這個男孩活了三萬年，一年對他來說感覺也像一天

And if this boy's emotions sustain through the potential boredom of living for millions of years,

而若是這個男孩的情緒支撐過了可能伴隨這百萬年而來的無聊

he might become extremely lonely and sad

他可能會變得極其孤單並且傷心

knowing he has and always will outlive everyone he has ever loved.

因為他知道自己總是且永遠都會活超過任何他所愛的人

But what if everyone were immortal?

然而要是所有人都長生不老呢？

Well, first off, Earth is only so big.

這樣呢，首先，地球也就這麼大

So, where would we all live?

所以我們要住哪裡？

"Excuse me!"

「不好意思！」

"That's my face!"

「那是我的臉！」

"Stop it!"

「別鬧了！」

"Pardon me."

「抱歉，」

"Tight in here!"

「太擠啦！」

Do you remember what you did last year?

你記得你去年做了什麼事嗎？

What about when you were five?

那你五歲時做過的事呢？

How much of your past have you forgotten?

你已經忘了多少你的過去？

If you're having trouble remembering what you did when you were five,

若是你沒辦法想起你五歲時做過的事

how will you remember what happened if you were alive a thousand years ago?

那你又如何想起自己一千年前做過的事？

A million years ago?

一百萬年前呢？

We don't remember every single detail of our past

我們不記得我們過去的每一個小細節

because our brains have a limited capacity

是因為我們的大腦承載有限

and we replace useless memories,

我們會換掉沒用的回憶

like middle school locker combinations,

比如中學櫃子的密碼

with relevant information.

還有相關的訊息

If this immortal boy finds a companion to fall in love with once every hundred years,

如果這個永生男孩每一百年就會找到一個伴侶陷入熱戀

he would have ten thousand girlfriends in a million years.

他在一萬年間至少會有一萬個女朋友

And how many of those ten thousand girls' names will he be able to remember?

而他又能記住其中多少女孩的名字？

This changes what a meaningful relationship means,

這可讓一段有意義的關係改變了意義

doesn't it?

不是嗎？

Another tricky thing about immortality:

另一件有關長生不老的小問題就是：

Human beings have not always looked the same.

人類並非總是長得一樣

This can be explained by Darwin's Theory of Evolution.

這可以用達爾文的演化論來解釋

For instance, if women find taller men more attractive,

舉例來說，要是女性覺得較高的男性比較有吸引力

then more tall men would mate and have children,

那麼較多的高個子男性能夠交配並且擁有後代

putting more tall genes in the gene pool.

使得基因庫裡擁有更多的高個子基因

That means, in the next generation, more children will have the genes to be taller.

那意味著，在下一代中有較多孩子會擁有高個子基因

Repeat that process for a million years and the average height will be a lot taller than the average height today,

重複這個過程一百萬年的話，平均身高就會比現今的要高上許多

assuming there's no natural disaster

前提是沒有自然災害

that wipes out all the tall people.

會消滅所有高個子

Our ancestors were short, hairy apes.

我們的祖先是又矮又多毛的人猿

We still have body hair, but we don't look like apes any more.

我們依然擁有體毛，但是我們不再長得像人猿了

If you're the only person who is immortal,

如果你是唯一長生不老的人

while everyone else keeps evolving generation after generation,

在其他人一代代持續演化的同時

you will eventually look quite different than the people who surround you.

你最終會看起來和周遭的人非常不一樣

"Hi, how you doing?"

「嗨，你好嗎？」

If one of our ancestor apes is still alive today,

如果我們其中一個人猿祖先至今還活著的話

how many people will make friends with it instead of calling the Museum of Natural History?

多少人會和牠做朋友，而不是打給自然歷史博物館？

And one more physical consideration for immortality:

另一項攸關生理的長生不老問題：

Scars.

疤痕

After all, immortality doesn't automatically translate to invincibility,

畢竟，長生不老並不會自動轉變為無堅不摧

it just means you cannot die.

那只代表了你不會死

But it doesn't guarantee what condition you'll be alive in.

但那並不能確保你會在什麼狀況下生存

So, look at your body

所以，看看你的身體

and count how many scars you have.

數一數你有多少疤痕

If you have made this many permanent scars within your life,

要是你至今已經有了那麼多永久的疤痕

imagine how much damage you would have if you were one thousand years old!

試想你要是一千歲了又會有多少傷痕！

Now, there are approximately

現今，在美國每年

185,000 amputation related hospital discharges every year in the U.S.

約有十八萬五千起醫院內截肢

These injuries are due to accidents or illnesses.

這些傷害是由於意外或是疾病

Certainly the percentage is low

是沒錯，相比全體人口

comparing to the total population

這個百分比還算低

if you only live for a hundred years.

但那是如果你只活了一百年的話

However, if you've been alive for over one million years,

然而，若是你已經活了超過一百萬年

the odds of still having all your limbs are pretty slim.

依舊保有你所有肢體的機率微乎其微

What about little accessories,

那麼其他小部位呢？

like your eyes,

比如你的眼睛、

your nose,

你的鼻子、

your ears,

你的耳朵、

fingers or toes?

手指或是腳趾？

What about your teeth?

你的牙齒呢？

What are the odds of you keeping your dental health

你能維持牙齒健康一百年的機率

for a hundred years?

會有多高？

A thousand years?

一千年呢？

One million years?

一百萬年？

You might end up looking like a horribly scuffed up Mr. Potato Head

你最後有可能看起來就像是恐怖的殘缺蛋頭先生

with missing pieces and dentures.

少了部件和牙齒

So, are you sure you want to live forever?

所以，你確定你想長生不老？

Now, which superpower physics lesson

現在，你接著想探索哪一個

will you explore next?

超能力物理課程？

Shifting body size and content,

改變身體大小和內含物、

super speed,

超高速、

flight,

飛行、

super strength,

超強神力、

immortality,

長生不老

and

以及

invisibility.

隱形