In movies, kings are always searching for the secret to immortality.
But is immortality really a good thing?
To a ten-year-old boy, one year is the same as 10% of his life.
To his forty-year-old mother, one year is merely 2.5% of her life.
The same year, 365 days,
can feel differently to different people.
If we live until we’re 82,
that’s about 30,000 days.
If this boy lives for 30,000 years, a year to him could feel like a day.
And if this boy’s emotions sustain
through the potential boredom of living for millions of years,
he might become extremely lonely and sad,
knowing he has and always will outlive everyone he has ever loved.
But what if everyone were immortal?
那么 首先 地球要非常大
Well, first off, Earth is only so big.
So, where would we all live?
“Excuse me!” “That’s my face!”
“Stop it!” “Pardon me.”
“Tight in here!”
Do you remember what you did last year or when you were five?
How much of your past have you forgotten?
If you have trouble remembering what you did when you were five,
how will you remember what happened if you were alive a thousand years ago?
A million years ago?
We don’t remember every single detail of our past
because our brains have a limited capacity
and we replace useless memories,
like middle school locker combinations,
with relevant information.
If this immortal boy finds a companion
to fall in love with once every hundred years,
he would have ten thousand girlfriends in a million years.
And how many of those ten thousand girls’ names
will he be able to remember?
This changes what a meaningful relationship means, doesn’t it?
Another tricky thing about immortality:
Human beings have not always looked the same.
This can be explained by Darwin’s theory of evolution.
For instance, if women find taller men more attractive,
then more tall men would mate and have children,
putting more tall genes in the gene pool.
That means, in the next generation,
more children will have the genes to be taller.
Repeat that process for a million years
and the average height will be a lot taller
than the average height today,
assuming there’s no natural disaster that wipes out all the tall people.
Our ancestors were short, hairy apes.
We still have body hair, but we don’t look like apes any more.
If you’re the only person who is immortal,
while everyone else keeps evolving,
generation after generation,
you will eventually look quite different than the people who surround you.
“Hi, how you doing?”
如果你的某个祖先 类人猿 现在还活着
If one of our ancestors, apes, is still alive today,
how many people will make friends with it
instead of calling the Museum of Natural History?
And one more physical consideration for immortality: Scars.
After all, immortality doesn’t automatically translate to invincibility,
it just means you cannot die.
But it doesn’t guarantee what condition you’ll be alive in.
Look at your body and count how many scars you have.
If you have made this many permanent scars within your life,
想想吧 活个上千年 你会有多少创伤
imagine how much damage you would have if you were one thousand years old!
Now, there are approximately
185,000 amputation-related hospital discharges every year in the U.S.
These injuries are due to accidents or illnesses.
Certainly the percentage is low comparing to the total population
if you only live for a hundred years.
However, if you’ve been alive for over one million years,
the odds of still having all your limbs are pretty slim.
What about little accessories,
比如你的眼睛 鼻子 耳朵啊
like your eyes, your nose, your ears,
fingers or toes?
What about your teeth?
What are the odds of you keeping your dental health for a hundred years?
A thousand years?
One million years?
You might end up looking like a horribly scuffed-up Mr. Potato Head
with missing pieces and dentures.
So, are you sure you want to live forever?
好了 接下来 你还想试试哪种超能力
Now, which superpower physics lesson will you explore next?
Shifting body size and content,