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Life is fundamentally different
from dead stuff—or is it?

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Physicist Erwin Schrödinger
defined life this way:

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Living things avoid decay into
disorder and equilibrium.

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What does this mean?

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Let’s pretend that your download
folder is the universe.

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It started orderly and got more
and more chaotic over time.

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By investing energy, you can create
order and clean it up.

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This is what living things do.

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But what is life?

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Every living thing on this
planet is made of cells.

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Basically, a cell is a protein-based robot
too small to feel or experience anything.

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It has the properties we just
assign to life:

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it has a wall that separates it from the
surroundings, creating order;

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it regulates itself and maintains
a constant state;

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it eats stuff to stay alive;

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it grows and develops;

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it reacts to the environment;

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and it’s subject to evolution;

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and it makes more of itself.

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But of all the stuff that makes up
a cell, no part is alive.

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Stuff reacts chemically with other stuff,
forming reactions

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that start other reactions which
start other reactions.

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In a single cell, every second several
million chemical reactions take place,

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forming a complex orchestra.

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A cell can build several thousand
types of protein:

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some very simple, some complex
micromachines.

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Imagine driving a car at 100 km/h while
constantly rebuilding every single

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part of it with stuff you collect
from the street.

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That is what cells do.

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But no part of the cell is alive;
everything is dead matter

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moved by the laws of the universe.

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So is life the aggregate of all these
reaction processes that are taking place?

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Eventually, every living thing will die.

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The goal of the whole process is to
prevent this by producing new entities;

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and by this, we mean DNA.

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Life is, in a way, just a lot of stuff
that carries genetic information around.

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Every living thing is subject to
evolution,

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and the DNA that develops the best living
thing around it will stay in the game.

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So, is DNA life, then?

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If you take DNA out of its hull,
it certainly is a very complex molecule,

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but it can’t do anything by itself.

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This is where viruses make everything
more complicated.

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They are basically strings of RNA
or DNA in a small hull

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and need cells to do something.

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We’re not sure if they count as
living or dead.

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And still, there are 225,000,000 m³
of viruses on Earth.

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They don’t seem to care what
we think of them.

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There are even viruses that invade
dead cells and reanimate them

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so they can be a host for them, which
blurs the line even more.

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Or mitochondria.

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They are the power plants of
most complex cells and

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were previously free living bacteria that
entered a partnership with bigger cells.

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They still have their own DNA and can
multiply on their own, but

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they are not alive anymore; they are dead.

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So they traded their own life for the
survival of their DNA,

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which means living things can evolve into
dead things as long as it’s beneficial

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to their genetic code.

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So, maybe life is information that manages
to ensure its continued existence.

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But what about AI
(artificial intelligence)?

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By our most common definitions, we are
very close to creating artificial life

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in computers.

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It’s just a question of time before the
technology we build gets there.

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And this is not science fiction, either;

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there are a lot of smart people
actively working on this.

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You could already argue that computer
viruses are alive.

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Hm, okay. So what is life, then?

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Things, processes, DNA, information?

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This got confusing very fast.

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One thing is for sure:

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the idea that life is fundamentally
different from non-living things

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because they contain some
non-physical element

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or are governed by different principles
than inanimate objects

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turned out to be wrong.

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Before Charles Darwin, humans drew a line
between themselves and the rest

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of living things; there was something
magical about us that made us special.

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Once we had to accept we are like every
living being, a product of evolution,

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we drew a different line.

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But the more we learn about what
computers can do and how life works,

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the closer we get to creating the first
machine that fits our desciption of life,

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the more our image of ourselves
is in danger again.

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And this will happen sooner or later.

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And here’s another question for you:

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if everything in the universe is made
of the same stuff,

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does this mean everything
in the universe is dead

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or that everything in the universe
is alive?

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That it’s just a question of complexity?

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Does this mean we can never die

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because we were never alive
in the first place?

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Is life and death an irrelevant question
and we haven’t noticed it yet?

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Is it possible we are much more part of
the universe around us than we thought?

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Don’t look at us; we don’t have any
answers for you.

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Just questions for you to think about.

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After all, it’s thinking about questions
like this that makes us feel alive

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and gives us some comfort.

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