- This episode of Because Science
is brought to you by Audible.
How confident are you that this is reality?
Given the rise of technology that can resolve
better and better images and interactions to feel
more and more like real life,
some tech experts and philosophers and even Elon Musk
think that there's a very good chance
that this isn't reality.
It's a simulation.
And I'm gonna try to convince you they might be right.
(upbeat music)
My favorite recent example of simulation theory
is in the fantastic show, Rick and Morty.
In one episode, aliens simulate environments
and even whole people in the hopes of tricking Rick
and stealing his formula for concentrated dark matter.
The idea is that if properly simulated,
Rick wouldn't be able to tell the difference
between what is real and what isn't.
Rick could tell the difference, but could we?
Now if I for example suddenly looked
like a Rick and Morty me.
Uh you you'd instantly be able to
(belches)
be able to tell that something was up,
but since I've always looked like this to you,
like a human person, how can you really tell
that I'm not a simulation?
The short answer is you can't.
One of the more famous arguments that philosophers
have among themselves about this is called
Zhuangzi dreamed he was a butterfly.
Zhuangzi was an influential fourth century
Chinese philosopher and one day he dreamed he was
living the life of a butterfly without a care in the world,
but when he awoke he realized that there was no way
to tell if he was dreaming the life of a butterfly,
or if the butterfly was dreaming the life of him.
So the argument goes that there's no real way
to determine whether or not everything you experience
outside of your own mind is a dream,
or whether or not you're just a brain in a jar
being fed simulations by some
(belches) evil scientist.
But we can still think of the probability
of whether or not we live in a simulation
and it's more likely than you may think think
think think think, no that'd be too obvious if it did that.
Our existential crisis starts with accepting
just two assertions.
The first is that everything that you experience,
everything that happens in your brain
is at some level information processing
that could in theory be replicated by technology.
Nothing immaterial or magical.
Most scientists agree that this is the case.
The second assertion is that one day because of this basis,
future humans might be able to create simulations
that are so good it would be like running human.exe.
Simulated minds living in simulated environments
without knowing that they are simulated.
Kind of like Rick and Morty's Roy.
If those two assertions hold true,
then if at any point future humans
can run simulations that are like us
and we can't determine what is reality anyway?
Those simulations are bound to outnumber
the single base reality, meaning that
by the numbers alone, we probably live in one of those.
But future humans running these simulations
is just one possibility.
Philosopher Nick Bostrom is the one who popularized
this simulation situation with the essay
Are You Living in a Computer Simulation
published in 2003.
He thinks it comes down to a trilemma.
Because it seems like technology is headed
in the direction of better and better simulations,
either humanity ends before we can run these simulations,
humanity can run these simulations but chooses not to
because the NPCs that we'd create would
think and feel
and then might have rights, or we live in a simulation.
It has to be one of
(belches) these, I'm sorry.
And Bostrom doesn't think that the part that puts us
in a simulation is the least likely option either.
Like .1% or 1%.
He figures our chances of being in a simulation right now
are between 20 and 50%.
Think about it this way.
The trilemma, if you accept those terms,
unless future humans never run simulations that are like us
people that have experiences like us,
then chances are we are simulations
inside of a simulation right now.
Like good chances.
You can...
Am I in a simulation?
Why can't I escape infinity room?
It's like that scene in the Matrix,
but the Matrix 2 it wasn't as good.
But of course this all still comes down to processing power.
Could we ever ever simulate everything you experience,
everyone around us, everything we see?
Bostrom is pretty optimistic about this.
He assumes that when future humans reach
a certain stage of technological progress,
we'll be able to do very singularity like things
like turn entire planets into computers.
Okay, kind of supervillainy dude, but all right sure.
Based on the physical limitations in media
that we know of for information processing,
a computer like this could perform
10 million trillion trillion trillion operations per second.
Now if 100 billion humans have ever lived
and on average each human lives for 50 years
and there's 30 million seconds
in a year that's Rent, don't sue me.
And estimates for the human brain
put the operations per second
at somewhere between trillions and quadrillions
and you divide that by the processing power
of an entire planet,
then you could simulate all of human history
without using more than a millionth
of the total processing power for this planet.
And it might not even take that much processing power.
If our simulation was run like a videogame,
then NPCs, everyone around you might only
be simulated just enough so that they seem sentient.
- My man!
- Thanks, or the world if you didn't see it
or interact with it it wouldn't have to be
loaded to save on processing power.
What if to save on processing power,
I didn't exist until you clicked on this video?
What if we're a simulation inside of a simulation?
Then where is base reality, am I just in your head?
Do you even have a head?
Oh no!
So, are we all simulations?
Well, if you accept the fact that future humans
might be able to run simulations that are as good as this,
then yes there is a nonzero very real chance
that right now you are a simulation
living inside of a simulation
thinking about how you are simulated.
Sounds scary, but does it matter?
No.
This is still reality to us and we still have
experiences that matter to us, and in an uncaring universe
I think that's the most we can ask for.
And if we are simulations right now
that means that future humans
didn't go extinct, which is cool.
And the best way to figure out how they set up our reality
would still be to rise above, to focus on science
because of, because of science.
(upbeat music)
Thank you so much for watching, Claire.
Make sure to follow me on Twitter @Sci_Phile
where you can tweet me ideas for future episodes
and on Instagram under the same handle
where I'm posting mini episodes of this show.
If you want even more of me, but just higher quality
check out ProjectAlpha.com and my new show
the S.P.A.A.C.E Program where I go to fictional worlds
and try to explain them, and if you want even more silliness
check out my new show
with my colleague Dan Casey called Muskwatch.
Where we get very silly about a very serious man, thanks.
And thanks again to Audible for sponsoring today's episode.
Audible has an incredible selection of audiobooks,
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I'd recommend checking out A Wrinkle in Time
before the Ava Duvernay film comes out
next year because it looks great,
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To get an audiobook and 30 day free trial of Audible,
head over to audible.com/because
because it's that easy.
W-w-wait wait, wait wait wait Morty.
If the sun, if the sun's outside of the planet
(belches) planet's atmosphere Morty
then how can we hear it scream?
Y-y-you know that there's no medium
like air in between the sun and the earth, Morty.
So sound waves can't travel 'cause they're pressure waves.
'Cause they're pressure waves Morty,
so if the sun, even if it was screaming
you wouldn't be able to hear it.
Try not to think about it.