Life is fundamentally different from dead stuff—or is it?
Physicist Erwin Schr?dinger defined life this way:
Living things avoid decay into disorder and equilibrium.
What does this mean?
Let’s pretend that your download folder is the universe.
It started orderly and got more and more chaotic over time.
By investing energy, you can create order and clean it up.
This is what living things do.
But what is life?
Every living thing on this planet is made of cells.
Basically, a cell is a protein-based robot too small to feel or experience anything.
It has the properties we just assign to life:
it has a wall that separates it from the surroundings, creating order;
it regulates itself and maintains a constant state;
it eats stuff to stay alive;
it grows and develops;
it reacts to the environment;
and it’s subject to evolution;
and it makes more of itself.
But of all the stuff that makes up a cell, no part is alive.
Stuff reacts chemically with other stuff, forming reactions
that start other reactions which start other reactions.
In a single cell, every second several million chemical reactions take place,
forming a complex orchestra.
A cell can build several thousand types of protein:
some very simple, some complex micromachines.
Imagine driving a car at 100 km/h while constantly rebuilding every single
part of it with stuff you collect from the street.
That is what cells do.
But no part of the cell is alive; everything is dead matter
moved by the laws of the universe.
So is life the aggregate of all these reaction processes that are taking place?
Eventually, every living thing will die.
The goal of the whole process is to prevent this by producing new entities;
and by this, we mean DNA.
Life is, in a way, just a lot of stuff that carries genetic information around.
Every living thing is subject to evolution,
and the DNA that develops the best living thing around it will stay in the game.
So, is DNA life, then?
If you take DNA out of its hull, it certainly is a very complex molecule,
but it can’t do anything by itself.
This is where viruses make everything more complicated.
They are basically strings of RNA or DNA in a small hull
and need cells to do something.
We’re not sure if they count as living or dead.
And still, there are 225,000,000 m3 of viruses on Earth.
They don’t seem to care what we think of them.
There are even viruses that invade dead cells and reanimate them
so they can be a host for them, which blurs the line even more.
Or mitochondria.
They are the power plants of most complex cells and
were previously free living bacteria that entered a partnership with bigger cells.
They still have their own DNA and can multiply on their own, but
they are not alive anymore; they are dead.
So they traded their own life for the survival of their DNA,
which means living things can evolve into dead things as long as it’s beneficial
to their genetic code.
So, maybe life is information that manages to ensure its continued existence.
But what about AI (artificial intelligence)?
By our most common definitions, we are very close to creating artificial life
in computers.
It’s just a question of time before the technology we build gets there.
And this is not science fiction, either;
there are a lot of smart people actively working on this.
You could already argue that computer viruses are alive.
Hm, okay. So what is life, then?
Things, processes, DNA, information?
This got confusing very fast.
One thing is for sure:
the idea that life is fundamentally different from non-living things
because they contain some non-physical element
or are governed by different principles than inanimate objects
turned out to be wrong.
Before Charles Darwin, humans drew a line between themselves and the rest
of living things; there was something magical about us that made us special.
Once we had to accept we are like every living being, a product of evolution,
we drew a different line.
But the more we learn about what computers can do and how life works,
the closer we get to creating the first machine that fits our desciption of life,
the more our image of ourselves is in danger again.
And this will happen sooner or later.
And here’s another question for you:
if everything in the universe is made of the same stuff,
does this mean everything in the universe is dead
or that everything in the universe is alive?
That it’s just a question of complexity?
Does this mean we can never die
because we were never alive in the first place?
Is life and death an irrelevant question and we haven’t noticed it yet?
Is it possible we are much more part of the universe around us than we thought?
Don’t look at us; we don’t have any answers for you.
Just questions for you to think about.
After all, it’s thinking about questions like this that makes us feel alive
and gives us some comfort.
Subtitles by the Amara.org community
活物和和死物有甚麼不同？
物理學家 Erwin Schr?dinger定義出 :
活物是避免衰敗和完全靜止活動的一種狀態
他的話是甚麼意思呢?
我們假設電腦裡的下載文件夾是宇宙
一開始放入的文件排放還相當整齊， 經過一段時間後，文件變多了，排序便會混亂起來
而透過消耗能量的方式， 你可以維持裡面的秩序和整潔
這就是活物所做的事
但生命究竟是甚麼？
地球上所有的活物都是由細胞組成
基本上，細胞是一個蛋白質機器， 他的尺寸小到無法感受到任何物質
它有生命的特質
包括：擁有隔離細胞內外的屏障、塑造秩序
它調節自己並且維持在一個恆量的狀態
它為了維持生命會吃東西
它會成長和發育
它會對環境做出反應
並且受演化的影響
及製造出更多的自己
但是所有組成細胞的物質，沒有一樣是有生命的
這些物質會和其他物質產生化學反應
這種化學反應又會誘發其他的化學反應
在一個細胞裡面， 每一秒鐘有百萬個化學反應在進行
形成一個複雜的化學反應交響樂隊
一個細胞可以組成幾千種蛋白質
有些蛋白質結構簡單，有些則複雜得像微型機器
想像你自己一邊開著時速100公裡的車
一邊利用路上撿來的的東西來重新建造這臺車
這就是細胞在做的事
細胞內沒有任何一個零件是活的
每個零件都是由宇宙的定律來驅動
所以應該說，生命是這些反應過程的聚集場所嗎？
活物終究會死亡
因此為了避免死亡， 這些化學反應的最終目的在於製造新的物質
而此物質便是DNA
生命的另一種說法就是： 一堆攜帶遺傳訊息的東西
每種活物都受制於演化
而擁有最贊DNA的生物 將會從這場遊戲中存活下來
這麼說來，DNA是活物羅？
如果你將DNA拿出來， 可以發現先它是一種非常複雜的分子
但是它自己本身並無法做任何事情
這就是為甚麼病毒讓生命的定義變得更加複雜
病毒的組成基本上是一個小殼包著幾串RNA或DNA
它們需要細胞的協助才可以做事
因此我們不確定它們是屬於活物或死物
而且地球上的病毒 體積高達2億2千5百萬平立方公尺
所以我想它們大概也不會有興趣我們怎麼看它們的
甚至有些病毒可以侵入死細胞，再賦予細胞生命
並且成為這些細胞的宿主 這讓生命與非生命的界線更加模糊了
另外一個例子是粒線體
它們是複雜細胞的能量工廠
粒線體的前身是細菌， 在進入比它體型大的細胞後，和細胞成為夥伴
粒線體仍有自己的DNA，並且有能力可以複製自己
但是它們已不是活物了，而是死物
所以我們可以說，粒線體用生命交換， 讓自己的DNA流傳下去
也就是說，只要對傳承遺傳物質有益處
活物也可以演化成死物
因此，生命可能是 能夠確保將自己的存在延續下去的資訊
那AI人工智慧又怎麼解釋呢？
如果以一般定義來說，
我們幾乎快要可以在電腦裡創造人工生命
而達到這種目標也只是時間的問題
這不是科幻片
已經有很多聰明的人在做這項工作
說到這裡，你可能會想爭論 電腦病毒是可以算是活的
嗯，好吧！所以甚麼是生命呢？
是東西？是過程？是DNA？是資訊？
好像很讓人困惑
但是有一件事一確定的
也就是剛剛所提的那些， 生命和非生命基本上是不同的
因為生命擁有一些非物質的元素
又或，生命是由不同的原則所掌控
這些觀念都是錯的！
在達爾文.查理斯出現之前 人類將自己和其他的生物做出區別
人類認為，過去曾有神奇的力量 讓我們比較特別
現在，我們知道我們和其他生物一樣， 都是演化下的產物
所以我們便做出另一種區別（生命vs非生命）
但是我們對電腦所能做的事 和生命的運轉懂得越多
我們就越快可以創造出像生命的機器
而我們對於自己的形象便會越快再次陷入危機
而這是早晚會發生的事
這裡有另一個問題
如果宇宙中的所有東西 都是由同一物質所組成
那宇宙中的所有東西都是死的嗎？
或宇宙中的所有東西都是活的呢？
又或這些只是複雜性的問題？
那麼也就是說 我們永遠不會死亡了嗎？
因為我們在最一開始就沒有活過了？
或是生與死是不相關的問題 而我們根本還沒注意到？
有可能我們在這個宇宙中的組成 比我們自己想像的還要多嗎？
不要問我，我也沒有答案
只是想問問這些問題 讓你可以思考一下
畢竟，在思考這些問題的時候 可以讓我們覺得自己還活著
讓我們感覺好受點