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Freeman: Do we live in the real world?
[ Alarm clock beeps ]
Or is it all in our minds?
Do we see the universe as it is?
Or do our senses deceive us?
Scientific observation reveals hidden realities.
The judgment of our senses cannot be trusted.
[ Engine revs ]
And our basic assumptions about life and the universe
may be false.
Is existence an illusion?
Is reality real?
Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
Subtital By RA_One
What is real?
We assume it's everything we encounter in our daily lives.
But how can we be certain
the universe we see around us actually exists?
And how can we know
that the world we see matches what anyone else experiences?
Our senses certainly make reality seem real enough.
These things are solid.
But...
What if they actually aren't?
Our reality may be a fragile tissue of illusions
illusions about ourselves, our society,
and even the whole of the natural world.
When I was young, a magician came to town.
He was pretty good.
Watching him made me doubt the reliability of my own eyes.
No matter how hard I looked, I couldn't see how he did it.
What was I missing?
And why was I missing it?
Lawrence rosenblum is a Professor
of perceptual psychology
at the university of California, riverside.
He also dabbles in magic.
More than most,
Larry understands the mechanisms magicians use to warp reality.
Man: Ladies and gentlemen, the amazing Larry!
Rosenblum: Good evening, ladies and gentlemen.
Tonight, I'd like to teach you a little bit about perception.
How did that trick work?
Well, as I was throwing the ball up,
you were following my eyes with your attention.
And that continued through the last throw,
which was not a real throw.
That technique of misdirection is just one
of the many techniques that professional magicians use.
Freeman: Illusionists like David gabbay perform tricks
that fool us again and again, no matter how closely we watch.
They take advantage of our brain's eagerness
to make sense of the world.
Rosenblum: David's not helping our brains create a reality
as much as guiding our attention of the perceptual information
in different ways.
And in that way, I think that David has a lot to teach us.
Freeman: David's trick exploits a mental shortcut
called amodal completion.
Here is how it works.
Let's say you see a rabbit.
Then your view of the rabbit is partially blocked.
Is the rabbit still there?
Of course.
You know that because your brain matches it up
with a three-dimensional model of a rabbit
you have filed in your memory.
Your brain fills in the missing piece.
Voilà!
Freeman: We have millions of these models stored in our minds.
We use them to assemble
a seemingly continuous picture of the world
what we think of as reality.
Our sense of reality is profoundly affected
by the way our senses work together.
For instance...
Bah, bah, bah, bah...
Freeman: What do you hear?
Bah, bah, bah...
Larry seems to be saying, "Bah, bah, bah."
but here's what happens when the picture is changed just a bit.
Fah, fah, fah, fah...
Freeman: Now it sounds like he is saying, "Fah, fah, fah."
but close your eyes and listen.
The sound hasn't changed.
Larry is still saying, "Bah," With a "B."
bah, bah, bah.
In the case with an auditory "Bah" And a visual "Vah,"
what happens is the visual information ends up
overriding the auditory information
because it's so salient.
It is so easy to see.
Bah, bah, bah.
And the perceptual brain, in this case,
mostly the auditory brain ends up using that information
to kind of push the "Bah" To sound more like a "Vah,"
and that's what people end up believing
they're actually hearing.
Freeman: Many different sensory systems interact within our brains.
Our minds take this information and tell a story about it.
We call it reality.
We're perceiving a lot more than we realize.
And what I mean by that is
that there are entire channels of information
that are getting to the brain
underneath our level of awareness.
But at any one time,
not only are you seeing something
and attending to what you're seeing,
but what you're not attending to is affecting you as well,
and that isn't just from information
you get through your eyes,
but information you get through your ears
and through your nose and through your skin.
And all of that is happening as we're sitting there
experiencing what we think is a visual reality.
The other senses are affecting it all.
Freeman: But for all we perceive, there is much we miss.
Most of us share the same set of senses.
Yet some of us see things very differently than others.
Can any of us perceive the world as it truly is?
Professor Charles Falco is one of the few who can.
He explores the invisible world the reality we can't see.
[ Camera shutter clicking ]
The human vision system only captures a really tiny fraction
of the light that's available.
If we look at a bust like this,
we see it looks red to the naked eye.
But if we image this in the ultraviolet,
possibly, this bust will fluoresce
because of some of the chemical composition that's in it.
Infrared typically penetrates fairly far through red pigment.
So we'll be able to see what's underneath the pigment,
if there's something between the pigment
and the plaster bust itself.
Freeman: In his laboratory at the university of Arizona,
Charles had exotic instruments that can examine objects
at resolutions across all ranges
of visible and invisible light
x-rays, ultraviolet, infrared,
and machines that see millions of times sharper
than human eyes.
This electron microscope can read the rough molecular surface
of the bust's seemingly smooth red paint.
The crown jewel of his collection
is a machine that reads the space between atoms,
giving physicists a completely different way
of looking at how molecules are constructed.
Falco: If you only have your eyes,
you look at something, you think you understand it.
Turns out that the more tools you have to look at something,
it reveals much more information.
So reality is a much more complex thing
than we think about.
The more ways we have studying of reality,
the more we realize reality is a bigger picture
than we could possibly have understood before.
Freeman: There is no evolutionary pressure
to create an animal that sees reality as it really is.
We have evolved to see the reality we need to see.
When we see something, how our brain interprets it
isn't usually what exactly is imprinted on our eyeball.
We're not a camera.
We have a brain behind our retinas.
And the brain processes the information
and tells us what it wants us to see.
There is so much visual information
in the world around us that it turns out
our brain gives us a limited spotlight of attention,
where we focus our attention on exactly what's in front of us,
ignoring things that go on everywhere else.
Freeman: When your attention's attracted by something,
neurons enhance the sensitivity
of the central region of your field of vision
and suppress the sensitivity of the surrounding regions.
And this is how we see the world through binoculars.
We see only a tiny fraction
of the reality that's in front of us.
There is so much sensory information,
so much visual information
that, in fact, it's impossible to process it all.
So everyone's brain, every animal's brain
has been programmed by evolution to accept
only a small fraction of the information and process it.
Otherwise, there'd be total overload.
Freeman: But reality isn't defined solely by how you or I see the world
it's something we share.
We check our observations
against the observations of others.
If we didn't agree on what is real and what is not,
society couldn't function.
But this man believes
our shared reality is the greatest illusion of all.
I am not real.
You are looking at thousands of glowing, colored dots
on a screen.
The pattern of these dots changes
once every 30th of a second,
creating the illusion of movement.
And I'm not saying these words right now.
This is a captured impression
of something I said in the recent past.
Or is it?
What if I did this?
You've been conditioned
to believe that, when something says "Live,"
it's really happening right now.
Our society is tied together by these shared beliefs.
But how much of it is real?
And how much is just an elaborate fantasy?
For much of his life,
scientist and philosopher Jim baggott has been haunted
by a simple question what is reality?
All reality is a fantasy created in our own heads.
We are locked in the prison of our own minds,
and as a consequence, we have to create for ourselves
an understanding of what reality is like
on the basis of what we can absorb,
what we can learn, what we can see.
[ Door creaks ]
So when we see with our eyes,
what we perceive, of course, is not reality as such.
Our brains are, after all, just clumps of tissue
weighing about 3½ pounds, with a consistency of cold porridge.
It's only when we interpret the electrical signals
generated by our brain in our conscious mind
do we create our individual reality.
That begs the question
what happens when those electrical signals are shut off?
Well, I'm about to find out.
Freeman: Jim's going to have his hearing and vision blocked out
for 15 minutes.
This simple form of sensory deprivation
sends him into an alternate reality.
He loses track of time...
[ Alarm clock rings ]
...and experiences vivid hallucinations.
In the absence of sensory input,
Jim's world-making machinery manufactures a reality
with no connection to the world outside his body.
Baggott: Deprived of two of my most important senses,
what happens is the brain scrambles for inputs
from other senses.
So you become very conscious of the taste in your mouth
and the hardness of this bed that I'm lying on.
I began to drift into some dreamlike states.
But then I became aware
that me eyes are, in fact, wide open,
and I'm fully awake and conscious.
Freeman: When your senses are shut off,
your brain makes up its own version of reality.
But according to Jim, we all live in a false reality
a hyperreality created by society,
filled with illusions that have become more real to us
than the physical world around us.
We are all part of a community of minds,
a world created by billions of brains working in concert
over thousands of years.
The modern consumer society
is the latest twist our mass mind has evolved
to advance the species.
Money lies at the heart of this society.
But in many ways,
it is the most hyperreal of all of our creations.
Baggott: I have here a $50 bill and a 50£ note.
Current currency-conversion rates tells us that the pound
is about 1½ times greater in value than the dollar.
And these little pieces of paper hold such a spell
over our lives.
They tell us whether almost
who is gonna live, who is gonna die.
But, really, value is something
that's part of the hyperreality that we've created,
and I don't know what the real value of a piece of paper
made of three parts cotton fiber and one part linen really is,
but I can tell you it's a lot less than $50 or 50£.
Freeman: Money would be valueless if we didn't all believe in it.
Our shared reality is an illusion
we have to struggle to maintain.
And if we fail to strictly observe its rules,
reality can crumble.
Baggott: Once these structures are out there, as it were,
they develop, you know, laws of their own.
They develop a life of their own almost.
And that misinterpreting those rules
and distorting those rules and changing those rules
we do that at our peril.
Freeman: There is perhaps no greater example
than the recent near collapse of the global financial system.
[ Atm beeping ]
Baggott: The global banking crisis of 2008
resulted from bankers playing with the rules of the game.
And as a consequence,
the value of money, literally overnight, was destroyed.
[ Bell ringing ]
Woman: Wall street is a panic after a record drop.
Freeman: For a brief moment, people became conscious
that money is essentially an illusion.
But if we stop believing in the global monetary system,
society could collapse.
So we choose to keep on believing.
Civilization was brought almost to its knees.
But the fact that civilization didn't disappear
perhaps tells us that hyperreality,
despite the fact that it exists only in our minds,
is still too tough to kill.
Freeman: Why is it so easy for us to live in a fantasy world?
What is it about being human
that compels us to create a hyperreality?
Is it social pressure?
[ Baby crying ]
Or is it born into us?
This neuroscientist believes the answer is buried
deep in our brains
and our denial of reality may be essential
to the survival of our species.
The human brain is a storyteller.
It tells us tales about the way things are,
and it allows us to imagine the way things could be.
But what if the stories we tell ourselves aren't true?
How would we know?
What if all our brains are wired to lie about reality
and our place in it?
This man is about to ride his motorcycle
through the traffic-clogged streets of London.
When he does, he will enter an alternate reality.
[ Engine turns over ]
[ Engine revs ]
Motorcyclists make up less than one percent
of vehicle traffic in britain.
But they suffer 14% of total deaths and serious injuries.
Bikers in the U.S. are about 37 times more likely
to die in a crash than people in a car.
[ Siren wails ]
But in this man's reality, those numbers don't apply,
at least not to him.
Despite knowing the grim statistics,
he, like millions of other bikers,
continues to ride his motorcycle.
Why do so many people consistently disregard risk?
At university college London,
neuroscientist tali sharot has discovered
there's a reality-distortion mechanism
built into the human brain.
She wrote a book about it called "The optimism bias."
so the optimism bias
is our tendency to overestimate the positive things in our lives
and underestimate the likelihood of negative things in our lives.
So, for example,
people overestimate their success professionally,
their longevity.
They underestimate their likelihood
of suffering from cancer, of getting divorced.
We are more optimistic than realistic,
but most of us are oblivious to the fact.
We're not aware of it.
Freeman: Nearly 80% of the population is affected by this bias.
It's easy to see it in action,
as tali demonstrates with a random group of students.
So, I'm gonna give you a list of abilities and characteristics,
and I want you to think, for each of these abilities,
where you stand relative to the rest of the population.
So, the first one is getting along well with others.
Who believes they are at the bottom 25%?
Okay. No one. [ Chuckles ]
Who thinks they are at the top 50%?
Okay. So that's most people.
So, what we find is
that most people rate themselves above average on most abilities.
And that's, of course, statistically impossible,
'cause we can't all be better than everyone else.
Who here thinks that they will have talented kids?
That's most of us here.
And who here thinks they will be successful
in their professional life?
Freeman: It's commonly believed
that, when your expectations are not met,
you alter your expectations.
Yet tali's experiments show that most people,
despite all evidence to the contrary,
remain optimistic in the face of reality.
She decided to find out why.
Using a brain scanner,
tali monitors what happens in our heads
when we process information.
Today, this man will learn
if he's out of touch with the real world.
Sharot: Okay, so you're gonna see the negative life events,
such as cancer,
and what you need to do is estimate your likelihood
of experiencing this event in your lifetime.
Then you will see the average likelihood
of someone like you experiencing that event.
Freeman: Nick the biker will be asked to calculate his chances
of experiencing 80 different negative events in the future.
Nick thinks his chances of getting lung cancer
are about 10%.
Actually, it's 30% for a man of his age and lifestyle.
Now he's presented with more negative events.
With each new scenario,
he gives a prediction before finding out the real statistic.
When Nick hears good news,
his brain scans show plenty of activity in the frontal lobes.
But when he hears bad news, there is much less activity.
Now Nick will take the test again
to see whether these facts have changed his beliefs.
Sharot: What we usually find, again and again,
is that people change their estimates quite a lot
in the second session for items where they got information
that was better than their own estimates.
So, for example, if Nick says
that his likelihood of suffering from Alzheimer's is about 30%,
and we tell him,
well, the average likelihood of Alzheimer's is only 10%,
we find that most people change their estimates
the second time around.
They would say, "Well, maybe my average likelihood
of Alzheimer's is only about 12%."
and we see, in the frontal lobes,
enhanced activity when people get information
that's better than what they expected.
Freeman: But when people get information that's worse than expected,
it doesn't sink in.
Despite being told he has a 30% chance of dying of lung cancer,
Nick barely changes his estimate from 10% to 13%.
Our brains seem to resist negative information,
but only when it applies to us.
Sharot: So we're mostly optimistic about ourselves,
and we're optimistic about our kids, about our families,
but we're not optimistic about other people.
So people tend to be even slightly pessimistic
about the future of the country and the future of the world.
People do have quite pessimistic expectations
of where the economy is going, for example,
but they tend to think that they will be okay.
Freeman: And this is why the warnings on cigarette packages go unheeded.
Yes, smoking kills six million people a year.
But smokers believe that it kills the other guy.
They are unique. They will survive.
[ Inhales deeply ]
Freeman: That's the downside of living in a false reality.
But there is a strong positive aspect to it, as well.
So, optimism changes the way we see the world.
Man: Nelson mandela!
Sharot: But it also changes objective reality.
And it does so because it acts as a self-fulfilling prophecy.
So positive expectations changes our actions and our interactions
with the people around us, with the world,
and that actually changes the world around us.
Freeman: And this reality-distortion field, tali believes,
is essential to the survival and advancement of the human race.
Hope may not always be realistic,
but it makes the world a better place.
We all live in many realities.
There is the reality in our minds,
and there is the reality we share with others.
We now know these realities can't be entirely trusted.
But what about the physical world
that exists outside of our minds?
Surely,
in the rock-solid cause- and-effect world of nature,
we can rely on things to be indisputably real.
Maybe not.
In many ways, we are blind to the true nature of reality.
Our perceptions are limited.
Our brains distort the truth.
So can we ever know what is real?
That's the mission of science
to probe deep into the massive puzzle box of nature
to find its ultimate truths.
But how successful have we been?
What if we are blind to an entire extra dimension of space?
There are two kinds of physicists
theoreticians, who make informed guesses
as to why the world works the way it does,
and experimentalists,
who break things apart to see what's inside.
Steve nahn is an experimentalist.
I absolutely believe that reality is a real thing,
but that does not mean that we completely understand it.
When you look at the first maps of the world,
what you notice immediately is there are major pieces missing.
But as we explored more,
our accuracy on the maps got much, much better,
and we discovered continents,
like the americas or Antarctica or Australia.
Today, thanks to satellites, our maps are incredibly accurate.
But when it comes to the deeper levels of reality,
we're kind of like those first maps here.
We don't know everything that's out there.
Freeman: Physicists map the subatomic levels of reality
using the large hadron collider in Geneva.
The lhc is the biggest microscope in the world.
It smashes together protons
at 99.999999 percent of the speed of light.
Steve was one of the small army of scientists
who found the signature traces of the higgs field in July 2012.
The higgs field is responsible for the existence of matter
in the universe.
But this remarkable discovery may be just the beginning.
Many more strange things could emerge from the lhc...
Perhaps even gateways to unseen new realities.
Huh?
There may be dimensions of space and time
beyond the ones we know,
dimensions that could explain one of the greatest mysteries
of physics.
There are four fundamental forces
that drive everything we know.
There is the electromagnetic force,
there is the strong force and the weak force,
and then there's the one that we know the least about,
and that's gravity.
Gravity is a trillion, trillion, trillion times weaker
than the scale of those other forces.
So what's going on with gravity?
Why is it so much weaker?
That's one of the questions we'd like to be answer at the lhc.
Freeman: Many physicists suspect the three dimensions we know
are slices of a much larger universe.
In other, as yet undetected, dimensions,
gravity may be as strong as the other three forces.
The proof would be discovering high-energy clones
of familiar particles.
Nahn: Suppose that you found some new particles
that were sort of kissing cousins
to the particles you love and know,
only at higher mass.
So for each electron,
you have another electron that's at much higher mass.
And for each quark, you have another quark at higher mass.
And that would be a signature for extra dimensions,
and it would actually provide, possibly, a clue
for what's going on with gravity.
Because some particles can travel in this extra dimension,
and some particles cannot.
But if you could go off in that extra dimension
somewhere further away,
gravity becomes just as strong as the other forces.
Freeman: Things would be very different in this hidden reality.
For one thing, they would be much heavier.
Nahn: Take this basketball.
Let's pretend that it is a particle
that can travel in the extra dimension.
If it's here where we are, in that extra dimension,
and I drop it, gravity pulls it to the ground,
and the floor is strong enough
to push it back up into my hands.
But suppose that it then moves
somewhere else in this extra dimension,
where gravity grows exponentially stronger.
If I drop it over there,
the floor wouldn't be strong enough at all...
...and the ball would go straight through the ground,
crashing through the building below us.
Freeman: Back at the large hadron collider in Geneva,
the beams will soon be smashing together with enough force
to prove whether or not
this gravity-heavy dimension actually exists.
The lhc may shake up the orthodoxy
by proving these theories right or wrong.
I myself do not take sides.
My job is to find out what is really there
and what is really not there.
There are many different possibilities.
Like the mapmakers of old, we are exploring terra incognita
and trying to draw new maps of the true nature of reality.
Freeman: The universe may have more dimensions
than the ones we know.
But there is another even more radical possibility.
What if there are fewer dimensions than we think?
What if there is less to reality than there appears to be?
We live in a world of cause and effect.
The universe appears to behave in predictable ways.
But down deep, at the subatomic level,
reality shifts and changes.
The world we know gives way to quantum strangeness,
where all realities happen at once,
and the outcome of any event is unknowable.
Can an object be in two places at once?
Can things appear out of thin air?
Not in the reality we live in.
But nature has many layers.
And the closer we look,
the more we find reality as we know it breaks down
and magic is real.
Okay, guys. An amazing sleight of hand.
Just follow the coin, guess the hand.
You ready?
Do this one again to see...
Freeman: David tong is not a professional magician.
He's a theoretical physicist
at Cambridge university centre for mathematical sciences,
where he studies the magic of the quantum world.
[ Coin drops ]
[ Chuckles ]
Okay, in my defense, I could argue
that this is just an example of quantum uncertainty.
For particles like electrons,
you never know where they're gonna be
from one minute to the next.
In fact,
by the time you go down to the fundamental level of reality,
it looks like everything is something of an illusion.
Freeman: In the subatomic world, at the smallest known level of reality,
particles like electrons don't obey the laws of common sense.
They obey the laws of quantum mechanics.
In the quantum world,
the properties that a particle seems to have
depends on the experiment you do.
You can measure the position of a particle
with as much accuracy as you like,
or you can measure its speed,
but you can't measure both at the same time.
Similarly, an electron can appear as a particle or a wave,
but never as both at the same time.
Quantum objects are fuzzy, like the edges of shadows.
It doesn't make sense, but this really is the way nature works
at the most fundamental level.
Tong: Quantum mechanics is simply the best scientific theory
that we've ever developed.
It underpins everything we understand about the universe.
It's never been found to be wrong.
But where does this leave us?
What is the true reality?
Freeman: The prevailing theory of quantum mechanics
suggests we will never know
because we can never measure all of the properties
of quantum objects with absolute certainty.
It's like the story of Plato's cave.
2,000 years ago, the Greek philosopher Plato suggested
that we could never understand the true meaning of reality.
He said we were a little like prisoners,
chained in a cave and forced to look at the back wall.
Behind the prisoners,
there is a distant fire which throws shadows over them,
shadows of the life that's going on behind the prisoners.
But they never get to see that life.
All they see are the shadows.
And after a while,
they think reality is some two-dimensional dancing image.
They've got no way of ever turning around
and seeing this beautiful, colorful three-dimensional world
behind them.
Now, this is a little bit like quantum mechanics.
We can never understand everything
about the quantum wave.
We can never measure all of the information
which is contained in it.
All we can see are projections,
like the shadows of the true reality.
Freeman: But David says the truth may be even stranger than that.
The shadows on the wall may be the true reality.
This is the contention of the holographic principle.
Mathematicians attempted to calculate
the amount of information you can cram into a black hole.
They realized the amount is proportional
to its surface area, not to its volume.
And if this is true for a black hole,
they reasoned, it's probably true for any region in space.
Right now, we could all be inside a huge black hole
and not even know it.
Reality may actually be two-dimensional.
Think of everything in the universe as bits of information,
like the information stored in the books on this wall.
When the books lie flat like this,
they appear two-dimensional.
But, of course, when I pull them out,
we see that the books are three-dimensional at heart.
The information is three-dimensional.
The holographic principle says that this is an illusion
not just this, but you, me, the earth, the stars,
even space itself
everything that's three-dimensional
is actually an illusion.
The true reality is the books lining the wall.
The true reality lives in two dimensions.
Freeman: And this explains why quantum objects look fuzzy to us.
They are projections
that don't actually exist in three-dimensional space.
Tong: And what we think of as this three-dimensional world
is just a holographic projection
from a surface somewhere in the universe
to create the space we see.
It's as if Plato's prisoners had it right all along.
The shadows are real.
What's behind them was the illusion.
Freeman: Right now, there is no way to prove
whether the holographic principle
is the genuine description of reality
or the shared delusion of theoretical physicists.
But there may be another explanation
for quantum weirdness.
What if reality gets blurry
because it was never there to begin with?
Some scientists say
our reality could be a deliberately created illusion.
Using the tools of science,
we catch glimpses of the vast structure of creation.
There is so much we cannot see.
Why is the truth so hard to find?
Perhaps it's because the universe we live in
is just a small part of a larger reality...
And we are all just living in a world of dreams.
[ Alarm blaring ]
[ Alarm beeps, blaring stops ]
Have you ever had a recursive dream...
[ Alarm blaring ]
[ Alarm beeps, blaring stops ]
...a dream with a dream within a dream?
[ Alarm blaring ]
[ Alarm beeps, blaring stops ]
Jan westerhoff has.
And for all he knows, he might still be dreaming.
Or you might be dreaming this.
Westerhoff: How do you know whether waking up this morning
was actually a real awakening?
Perhaps you just woke up into another dream.
The reason why you should worry about this
is that there is actually a significant chance
that we are dreaming right now.
Let's do the numbers.
Freeman: According to jan,
most people spend 8 hours asleep and 16 hours awake every day.
About 20% of sleep is spent in the r.E.M. State,
when you dream.
20% of 8 is 1.6, which means...
Westerhoff: We know that, at this very moment,
you have a 1 in 10 chance of dreaming right now,
which is actually quite a significant probability.
Freeman: Jan doesn't actually believe he lives in a dreamworld,
but as a philosopher at the university of durham in england,
his job is to question how and why things are the way they are.
And despite what the numbers say,
logic tells you you are probably not asleep.
If this was a dreamworld,
why would it be bound by the laws of causality?
Why don't fire-breathing dragons go rampaging through London,
destroying the city?
Well, they don't.
What you saw was just an illusion.
Reality follows a strict set of rules,
even though it gets a little blurry at the quantum level.
What might explain that?
Well, perhaps we are living in a simulation
made by a higher-order reality.
Freeman: In other words, reality may not be a dream,
but it could be a computer simulation.
Imagine a time, perhaps centuries from now,
when our descendants have the power
to model fully functional human brains in computers.
These simulated minds could be placed
in computer-simulated worlds,
perhaps even re-creations of the past.
They would never know they weren't real.
What if this has already happened?
Westerhoff: How do we know that the present year we are in here
is actually the original rather than some sort of rerun
where some weird event in the past had been changed
just to see what kind of ramifications it had?
Freeman: Believe it or not,
there is a chance we are all part of a giant simulation.
Imagine, for example, that I buy a dalí print.
I get really excited about this
because I just love melting clocks.
Now the problem here is that, according to experts,
about 90% of all dalí prints on the market are fake.
So the chance that I've got a fake here is 0.9.
Huh?
Freeman: What are the odds that our world is a fake?
Huh?
Huh?
Some say as high as 1 in 20.
But jan says the percentage isn't important.
If there is any chance at all that you are simulated,
then you can't dismiss the possibility
that you are simulated.
But here is the thing
even if this is all a dream, does it really matter?
Even if this is just a dream cake
and I paid for it with dream money, it still tastes great.
So presupposing this all continues,
does it really matter whether it's a dream or a simulation?
I can still plan my life, causes will have effects,
and actions will have consequences.
Is reality real?
It certainly seems real to us.
But we now know the reality we perceive
is just a small slice of what really is.
And, perhaps, in the long run, that doesn't matter.
What matters most to us is the reality we know.
As the philosopher-king Marcus aurelius wrote
2,000 years ago, "The universe is change.
Our life is what our thoughts make it."
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