What does a brain need to be healthy?
Well, it needs nutrients from the food you eat,
it needs oxygen from your blood,
plenty of water
but there's something else, something equally as important.
It needs other people.
Human beings are extremely social creatures.
We come together, we team up,
we share moments of intense joy and disappointment.
We don't just seek out other people to have a good time.
Your brain function depends
on the social web that you're in.
Your neurons require other people's neurons
to thrive and survive.
I want to show you how our brains
are fundamentally wired to work together...
How this social network that envelops us from birth
is vital for our survival.
Yeah? Ok!
Eagleman, voice-over: Understanding how brains
deal with each other allows us
to understand what bonds our species,
driving us to help one another.
And what makes us hate...
What allows acts of human violence.
It helps us to make sense of our past
and holds the key to our future.
There are 7 billion people
living today...
7 billion brains
moving, choosing, acting,
believing, and connecting with other brains.
Brains are traditionally studied in isolation.
But, in fact, much of circuitry of the brain
has to do with other brains.
We're fundamentally social creatures.
And our society is a complex web of interaction.
On any normal day, we intersect
with an enormous number of people.
Eagleman, voice-over: Our lives are built
on these intersections,
not just between us and our family
and friends and work colleagues,
but also between them and the people they meet.
Even the most basic encounter...
Like getting a cup of coffee...
Eagleman, voice-over: Relies on trust with a stranger.
Can I get a latte, please?
Definitely. Thanks.
Eagleman, voice-over: Everywhere we look,
we see complex social interactions...
relationships forming and breaking,
bonds of love and support,
social networking.
We clump into large groups to share our knowledge.
We got all these random spots in your brain
that get wired up
into an associative neural network.
Eagleman, voice-over: We work to impress each other.
And we swap ideas.
I'll stick around for any questions
that anyone has.
Thank you.
Eagleman, voice-over: Most research looks at
one brain at a time,
but that misses the fact
that a great deal of our brain activity
is dedicated to communicating with each other,
interpreting each other.
Our social drive is deeply rooted
in our neural circuitry.
Take a look at this film from the 1940s.
What do you see happening here?
Is this just a simple animation of some shapes
or something more?
Do you see a chase?
A fight? A love story?
The big one seems to be pushing
the little one around.
Seems like the two triangles
are in a little bit of a squabble.
There are relationships re
in terms of one is more dominant
than the other.
Eagleman, voice-over: Back in the 1940s,
psychologists Fritz heider and marianne simmel
created this film as part of an experiment.
The ball doesn't seem to want to be in there.
It's freaking out.
It's scared.
It looks like a trap to me.
It looks like the small triangle
is being shut out
and, like, trying to peer in.
They are paired in a way
that seems friendly.
Yeah! This is really fun.
It's fun, right? Ha ha!
Eagleman, voice-over: What heider and simmel found,
as I did, is how easy it is to look at moving shapes
and to see meaning and motives and emotion
all in the form of a social narrative.
I kind of get the sense that
they're cats and dogs.
It seemed like the big one might have been,
like his, uh, his dad or something.
Just call it more of, like, a mating ritual
two competitors going for one possible mate.
These are just shapes on a screen,
but we can't help but tell stories about them.
Why? It's because our brains are so primed
for social interaction
that we look for intention and relationships all around us.
One way we navigate the social world is
by judging other people's intentions.
Is she trying to be helpful?
Are we a trustworthy team?
Our brains are good at making these sorts of judgments.
And we do it constantly.
But do we learn this skill from life experience,
or are we born with it?
To figure out which one it is,
I've invited over some people
who don't have much experience with the world.
I've invited them to a puppet show.
These babies are all under 12 months old.
They're just beginning to explore the world around them.
You could say they're all a little short
on life experience.
We decided to run a simple experiment
developed at Yale university.
Here's a duck struggling to open a box.
One bear helps the duck.
The other is mean to the duck.
Ok, bowie, here you go. There are two puppets...
Eagleman, voice-over: When the show's over,
I let the babies choose a bear to play with.
want to play with?
Yeah? Ok, is that the one you want? All right.
Eagleman, voice-over: Almost every one of them
chooses the bear that's been kind.
These babies can't walk or talk.
And yet they already have the tools
to make judgments about others.
Yeah? Ok!
It's often assumed that trust is something
that we learn from our experience in the world.
But these experiments demonstrate
that even as babies, we come equipped
with social antennae
for feeling our way through the world.
The brain comes with inborn instincts
for figuring out who's trustworthy
and who's not.
Eagleman, voice-over: As we grow,
our social challenges become even more subtle and complex.
Understanding others is
one of the most demanding operations
that our brains perform.
They have to interpret words.
And, more than that, inflection,
facial expressions, body language.
"Does she like me?"
"Is he interested in what I'm saying?"
"Do they want my help?"
Society runs on our ability
to read each other's social signals.
Take that ability away
and the world becomes a very strange place.
Car enthusiast John robison has always struggled
to read other people.
Robison, voice-over: When I was a little boy,
I was bullied and rejected by other kids.
And that didn't happen with machines.
You know, I could stand, uh,
by, uh, a tractor on my grandparents' farm.
And I could learn how to adjust it.
And it wouldn't tease me or do anything bad.
It wouldn't run away. It would always be there.
And I could count on it.
And i... i guess I learned to make friends
with the machines
before I learned how to make friends with other people.
Eagleman, voice-over: In time, John's affinity for technology
took him to places his bullies could only dream of.
By 21, he was a roadie for the band kiss.
This was me back with, uh, kiss in the seventies.
Uh, I look older and fatter and stuff.
I don't look the same anymore.
Eagleman, voice-over: Surrounded by legendary
rock and roll excess,
his outlook remained different from other people's.
People would come up to me all the time.
And they would say, "what's this guy like,"
or, "what's that guy like?"
I would say, "yeah, their stage setup,
"they had sunn 2000s bass amps," or...
Or, "gene played sunn coliseums",
and we had seven bass amps chained together.
"We had 2,200 watts in the bass system for that."
But I maybe couldn't tell you the first thing
about the musicians who sang through them.
Now I realize that shows that I did
kind of live in a different world all those years...
a world of machines and equipment.
Eagleman, voice-over: When he was 40, John was diagnosed
with asperger's... a form of autism.
Many regions of the brain are engaged
during social interaction.
But in autism that brain activity
isn't seen as strongly.
And that's paralleled by diminished social skills.
I didn't really understand that there were
complex messages in faces
until I was well into adulthood
and learned about autism.
I knew that people could, uh, display signs of crazed anger.
But if you, um, asked about more subtle expressions...
you know, "I think you're sweet",
"and I wonder what you're hiding,"
or, "I'd really like to do that,"
or, "I wish you'd do this..." Or that.
I...I had no idea about things like that.
Eagleman, voice-over: But then came a transforming moment
in John's life.
In 2008, he was invited to Harvard medical school
to take part in an experiment on his brain
overseen by Dr. Alvaro pascual-Leone.
It was an attempt to try to understand
how activity in one area
affects activity in an area... In another area
and how that affects behavior.
Eagleman, voice-over: The experiment was only meant
to help the scientists gain greater knowledge
about the autistic brain,
but then something unexpected happened.
John was given
transcranial magnetic stimulation or tms.
Magnetic coils were placed next to his head
to generate minute electrical currents in the brain
and alter its activity.
The researchers targeted different regions of
John's brain to see whether interfering
with his brain activity had any effect on his behavior.
They would test me after the session.
I would go home kind of not knowing what to expect.
Eagleman, voice-over: At first there was no result.
But then they targeted
the dorsolateral prefrontal cortex...
a region involved
in flexible thinking and abstraction.
And something dramatic happened.
Somehow I became different.
He contacted us, uh... very excited
to say, you know, "the effects of the stimulation
"seemed to have unlocked something.
"And the effects is still lasting.
And I now can do things that I could never do."
After tms, I was able to, uh, sort of
read signals from other people
and understand what was going on.
So I listened to that, fascinated by it,
and thought, "ok, well, whatever.
It'll go away."
Uh, but it didn't. It...
It actually, um, remains something
that... that had really fundamentally changed in...
In him.
Eagleman, voice-over: Somehow, and entirely accidentally,
the tms had unlocked a whole new world for John.
vegetable sandwich
to bring home.
What have you got...
Robison, voice-over: I'd be tempted to say,
"I couldn't read people and now I can,"
but that's not really true.
Ok. How about
a full-size one of them...
Sure.
It's more accurate to say
I had no idea there were these messages emanating
from other people.
Tms showed me those messages.
And now that I'm aware that they're out there,
everything I do is different.
All of a sudden, you can walk around
and engage the world.
And it's a big, big thing.
Ok, thanks!
We don't know
exactly what happened neurobiologically. Um...
But I think it now offers the opportunity for us
to understand what behavioral modifications,
what interventions might be possible
to learn from him that we can then teach others.
Eagleman, voice-over: John's transformation is a reminder
that all the activities of the human brain,
including the subtle interplay of emotions and relationships,
are rooted in the detailed patterns
of trillions of electrochemical signals.
Eagleman, voice-over: Somehow, humans can look at
each other and study
the arrangement of facial muscles
and then process that information
into an understanding of other people's thoughts and emotions.
Eagleman, voice-over: It's an astonishing skill
because the cues are so subtle.
And the processing is so rapid
that the whole operation runs under your radar.
It only takes 33 milliseconds
for your brain to process basic information
about someone's facial expression
and start reacting to it.
So we're gonna put one electrode
right above your eyebrow...
Eagleman, voice-over: So how does it do that?
And the other right on your cheek.
Here we go. Great...
Eagleman, voice-over: I've invited a group of people
to run an experiment.
I've wired them up to a machine
that measures movements in their facial muscles.
And I've asked them to look at photographs of faces.
When participants are looking at a photograph
with a smile or a frown,
we see this activity on the graph
which indicates that their own facial muscles are moving.
Why?
Well, it turns out that
they are automatically mirroring with their own faces
the expressions that they're seeing.
That was fun, right?
The last one?
Yeah. Yeah, it was a fun test.
Eagleman, voice-over: But what purpose does
this mirroring serve?
I've invited a second group of people.
They're similar to the first group,
except for one thing.
This is the most lethal neurotoxin on the planet.
If you were to ingest even a fraction of this,
your brain could no longer tell your muscles how to contract
and you would die of total paralysis.
So it seems unlikely that anyone
would pay to have this injected into themselves, but they do.
This is known as botulinum toxin or Botox.
If you put it into your forehead muscles,
it paralyzes them to reduce wrinkling.
But there's a less well known side-effect.
Eagleman, voice-over: When our participants with Botox
went through the same tests,
their facial muscles responded less.
No surprise there.
But replicating an experiment out of Duke university,
we had both groups look at facial expressions.
And now they were asked to choose the word
that best described the emotion they were seeing.
Panic.
Panicked.
Upset.
Eagleman, voice-over: On average, the Botox group
was worse at identifying the emotions correctly.
Skeptical?
Eagleman, voice-over: It seems that
the lack of feedback from their facial muscles
impairs their ability to read other people.
The paralyzed faces of Botox users
not only makes it hard for us to tell what they're feeling,
those same frozen muscles make it hard for them to read us.
And that tells us something.
When I'm happy or sad,
part of that feeling relies on the unconscious feedback
from muscles in my face.
And our social brains take advantage of that...
so when we're trying to understand
what someone else is feeling, we try on their facial expression.
This automatic mirroring of expressions is
just one way in which we understand others.
The brain also has a deeper way...
one that's best explained at the movies.
One ticket, please.
Thank you.
Eagleman, voice-over: When we go to the movie theater,
we know full well that it's make-believe.
The people on the screen are just acting.
And yet we still react.
We gasp and flinch and cry.
Why do we fall for it?
To understand why we care about other people getting hurt,
you need to understand what happens in your brain
when you get hurt.
So imagine that somebody were to stab your hand
with a syringe needle.
That activates a network of areas in your brain
that we call the pain matrix.
Eagleman, voice-over: There's no single spot in the brain
where pain is processed.
Instead, the perception of pain arises
from several different areas networking together.
Strangely enough, this pain matrix is
at the heart of how we connect with others.
Eagleman, voice-over: Now, when you watch
someone else get stabbed,
your pain matrix becomes activated.
Not the parts that tell you you've actually been touched,
but the parts involved
in the emotional experience of pain.
In other words, watching someone else in pain
and being in pain use the same neural machinery.
And that's the basis of empathy.
To empathize with another person
is to literally feel their pain.
You run a compelling simulation
of what it would be like if you were in that situation.
And our capacity to do this is why stories and movies
and novels are so absorbing
and why they're so pervasive across human culture.
Because whether it's about total strangers
or made-up characters,
you experience their agony and their ecstasy.
You fluidly become them
and live their lives and stand in their vantage points.
You can tell yourself that the stories aren't real,
but some neurons deep in your brain can't tell the difference.
Eagleman, voice-over: Our capacity to feel
another person's pain is part of what makes us
so good at taking other people's perspective...
to step out of our shoes and into their shoes,
neurally speaking.
Eagleman, voice-over: We can't help but connect with others.
We're hardwired to be extremely social creatures.
And that raises a question.
What would happen if the brain were starved of human contact?
In 2009, peace activist Sarah shourd
and her two companions were hiking in the mountains
of northern Iraq... an area that was at the time peaceful.
But they accidentally strayed into Iran,
and they were arrested.
They pulled us apart
and threw us in separate cells
and slammed the door.
And, um, that was the beginning of...
of the next 410 days of my life in that cell.
Well, in the early weeks and, really, months
of solitary confinement, you're reduced
to an animal-like state.
I mean, you are an animal in a cage.
And the majority of your hours are pacing.
And the animal-like state
sort of eventually transformed
into a more plant-like state...
When your mind starts to slow down
and your thoughts become repetitive.
Shourd, voice-over: Your brain turns on itself.
And it becomes the... the source of your worst pain
and your worst torture.
I would relive every detail of my life.
And eventually, you run out of... of memories.
And you've told them all to yourself
so many times, and it doesn't take that long.
Eagleman, voice-over: Extreme social depravation
causes deep psychological pain.
Without interaction, the brain suffers.
Solitary confinement is designed to eat away at
and really attack what essentially makes us human.
Eagleman, voice-over: Sarah's brain used
the scant sensory information it had to construct a reality.
The sun would come in at a certain time of day
at an angle through my window.
And all of the little dust particles in my cell
were illuminated by the sun.
I saw all of those particles of dust as being
other human beings occupying the planet.
And they were in the stream of life.
They were interacting. They were bouncing off one another.
They were doing something collective.
And I saw myself as off in a corner, you know,
walled off by... by myself out of the stream of life.
Eagleman, voice-over: In September 2010
after 410 days in solitary confinement,
Sarah was finally released and allowed to rejoin the world.
But for a long time, she suffered
from extreme post-traumatic stress.
The philosopher Martin heidegger said
we can't talk about being.
We can only talking about being in the world.
In other words, the world around you is a part of who you are.
In a vacuum, you lose your sense of self.
It's not easy for science to study people
while they're experiencing solitary confinement,
but a simple experiment
designed by neuroscientist Naomi eisenberger can give us
an insight into what's happening in the brain
when we feel excluded.
It's based on a game of catch.
While volunteers played a computer game of catch,
eisenberger and her team scanned their brains.
The volunteers thought the other characters were controlled
by other participants,
but, in fact, they were just part of the computer program.
At first, the other characters played nicely,
but after a while, they'd cut the volunteer out of the game
and simply play between themselves.
She found that being left out of the game
activated the pain matrix.
Not getting the ball might seem insignificant,
but to the brain,
social rejection is so meaningful
that it hurts.
Eagleman, voice-over: But that pain, in turn, is useful.
It pushes us in the direction of bonding with others.
We all seek out alliances.
We join with friends, with family, with colleagues.
It could be which team we support...
What style we go for...
What our hobbies are.
It gives comfort to belong to a group.
And that gives us a critical clue
into our success as a species.
Survival of the fittest isn't just about individuals.
It's also about groups.
We're safer. We're more productive.
We overcome challenges.
The drive to work in groups has helped human populations thrive
across the planet
and build entire civilizations.
And yet there's a flipside to this drive to come together.
Because for every "in" group, there are outsiders.
And the consequences of that can be very dark.
History is plagued with examples
of one group turning on another that was defenseless
and posed no threat.
If you were to look at my family tree,
you would see that most of the branches end
in the early 1940s.
This is because my family is ethnically Jewish.
That small social marker was enough
to prompt Nazi genocide.
Under normal circumstances,
you wouldn't find it conscionable
to go murder your neighbor.
So what is it that allows hundreds or thousands of people
to suddenly do exactly that?
What is it about certain situations
that short-circuits the normal social functioning of the brain?
While the Nazi holocaust was on an unprecedented scale,
it wasn't unique.
Genocide continued to occur all over the world.
And within a generation, it returned to eastern Europe.
This time, it was in yugoslavia.
The Bosnian war from 1992 to '95
saw atrocities on both sides.
In one of the worst, more than 100,000 Bosnian muslims,
known as bosniaks, were slaughtered
by serbians in actions known as ethnic cleansing.
One of the most horrible incidents
happened here at srebrenica.
Eagleman, voice-over: Over the course of just 10 days,
8,000 people were systematically killed.
How does something like this happen?
Here in 1995, thousands of bosniaks took refuge
inside this united nations compound,
because this village was surrounded by siege forces.
But then on July 11th, the u.N. Commanders made the decision
to expel all the refugees.
And they delivered them right into the hands of their enemies,
who were waiting just outside this gate.
Women were raped,
and men were executed, and even children were killed.
And this was just the beginning of what would be
the largest genocide on European soil since the holocaust.
The Dutch were there.
I mean, the world was there. You know, the u.N.
The serbs were there as perpetrators.
Everything was mixed.
The refuges were there, the babies were crying.
I was there being protected with that u.N. I.D. Card
that said "u.N. Language assistant," whatever.
Eagleman, voice-over: Hasan nuhanovic's status
as a u.N. Translator made him part of a protected group.
But his family members were marked out
by their identity as muslims.
At that very moment when my family
was being sent out of the compound
to actually die, I lost my...
I lost my mother, my brother,
and my father.
You know, like, you are in a situation
when your family is being killed.
And I was thinking, my god...
I mean, why?
Eagleman, voice-over: One of the most striking things is
that the perpetrators weren't strangers.
They were people with whom
his family had previously shared a great deal.
The continuation, you know, of...
Of the killings, of torture,
was perpetrated by our neighbors.
You know?
The very people we have been living
with for decades.
They were capable of killing
their own school friends.
I remember they said
they arrested a dentist
who was a bosniak,
the best dentist in the town.
They tied him up from a light pole,
like this in front of the post office.
He was hanging there like this.
And they beat him with a metal bar.
They broke his spine.
And he was there dying for days
while serb children went to school,
walking by his body, you know?
I mean, there are universal values.
And these universal values
are kind of very basic:
Don't kill...
April '92, this don't kill
suddenly disappeared.
It was like, "go and kill."
It was, allowed to kill.
This is where hasan's family is buried.
And each year, there are new bodies
that are found and identified,
and they're brought here.
Many of these graves are fresh.
And across the human species,
this is just one genocide of many.
Genocides keep happening...
Rwanda, Darfur, nanking, Armenia.
And my interest is in understanding why.
Traditionally we ask this question
through the lens of history or economics or politics.
And those are all important vantage points.
But I think for a complete picture,
one more lens is needed.
We need to understand genocide as a neural phenomenon.
I've been researching this back in my laboratory.
And here is my main question, when we interact with someone,
does our brain function differ
according to which group they are in?
For every "in" group we belong to,
there's at least one group that we don't.
And that division can be based on anything...
race or gender or wealth or religion.
We put 130 participants in this scanner.
Eagleman, voice-over: And here's what they saw...
six hands on the screen.
And the computer randomly picks one of these.
And then that hand gets stabbed by a syringe needle.
Now, that activates the pain matrix,
which is what comes on line
when you're in pain or you see someone else in pain.
Now here's the trick...
we now added a label to each hand...
Jewish, Christian, Muslim, hindu, atheist, scientologist.
Would they care as much
when they see a member of their out group getting stabbed?
So here's what we found:
Here's a subject.
And when he watched
a member of his "in" group
getting stabbed, there was a large neural response
in this area of his brain.
But when he watched a member of one of his "out" groups
get stabbed, there was essentially a flat line.
We scanned a range of volunteers.
And there are individual differences,
but the trend is clear.
A single word label is enough to change
your brain's basic pre-conscious response
to another person in pain...
in other words, how much you care about them.
Now, you might have opinions about religion
and its historical divisiveness,
but even atheists here care more
about other atheists' hands getting stabbed
than they do about other people.
So it's not really about religion.
It's about which team you're on.
This is just the first step in understanding
how we get to this.
To understand how groups of people can commit atrocities,
it can help to look at the behavior of individuals
like psychopaths.
Some of the most callous, inhumane crimes ever recorded
have been committed by psychopaths.
But what's different about their brains
that allows them to act that way?
There are networks in the medial prefrontal cortex
that underlie social interaction.
When we interact with other people,
this area becomes active.
But in the brain of someone with extreme psychopathy,
this area has a lot less activity.
A psychopath doesn't care about you.
He might be able to run a simulation
of what you're going to do or how you might react,
but when it comes to an emotional understanding
of what it's like to be you, he doesn't get that.
To him you're just an obstacle
to be worked around or manipulated
rather than a fellow human being.
So what accounts for genocide?
Is it driven by armies of psychopaths?
Well, that can't be it
because psychopaths only make up
a small fraction of the population,
but genocide typically engages a wider community.
So here's the question:
How do you get ordinary citizens on board?
At the university of leiden in Holland,
Dr. lasana Harris has been conducting an experiment
to understand a piece of this puzzle.
So now we're going to start the experiment.
What you're going to see is
a bunch of pictures of different people.
Your job is just to react naturally to those pictures.
Eagleman, voice-over: Lasana is looking at activity
in the brain areas involved in human social interaction,
in particular, the medial prefrontal cortex.
This comes on line when we think about other people.
It's less active
when dealing with something inanimate, like a cup.
What lasana found is that this region has
a similarly low response
when we deal with certain types of other people.
What he sees now are stereotypical images
of people from different social groups.
What we see here is at this network of brain regions,
including medial prefrontal cortex,
is less active when our participant
looks at the homeless people.
So what this pattern of activity suggests
is a type of mental avoidance.
They are not thinking about the mind of the homeless person
in the same way they thought
about the mind of the college students
that they saw or the businesspeople.
So if for instance you imagine
that interacting with a homeless person
will be unpleasant, it will make you will feel bad.
You may feel some demand to donate some of your money
and all of these unpleasant pressures
that come along with it.
By shutting off those systems,
you never experience those feelings.
Eagleman, voice-over: To a brain that responds this way,
homeless people are dehumanized.
They're viewed more like objects.
And that can enable us to not care.
Of course if you don't properly diagnose
this person as a human being, which is happening here,
then the different moral rules we have
that are reserved for human people may not apply.
Eagleman, voice-over: So under the right circumstances,
our brain activity can look more like a psychopath's.
But to understand how we can get to genocide,
we need to understand one more thing about group behavior.
Genocide is only possible
when dehumanization happens on a massive scale.
Not just a few individuals,
but whole sections of the population.
We're talking about a group of people committing atrocities.
Eagleman, voice-over: And if all the members
of that perpetrating group are complicit,
it's as if they've all somehow experienced
the same reduction in brain activity
when they think about their "out" group.
This can be understood and studied
like a disease outbreak,
a kind of group contagion...
one that's most often spread deliberately.
The perfect tool for this job is propaganda.
It plugs right into neural networks,
and it dials down the degree
to which we care about other people.
Just like all sites of genocide,
that's what happened in the former yugoslavia.
The people who went on to torture and kill
their neighbors were bombarded with propaganda.
State-controlled broadcasters demonized
the Bosnian muslims with distorted news stories.
I read you from the beginning
that somebody is, uh, helping muslims, uh, and arming them.
Eagleman, voice-over: They went so far as to claim
that the muslims were feeding serbian children
to the lions at the zoo.
Across place and time,
the language of propaganda changes very little.
It always plays the familiar tune of dehumanization:
Make your enemy less than human, make them like an animal.
Propaganda is a weapon.
And over the course of human history, it's become an art
and a science.
And it's become
ever more dangerous.
Eagleman, voice-over: In our connected age,
any extremist group
can reach millions of people with a keystroke.
The Internet is the perfect carrier for propaganda messages
to reach the people most likely to act upon them...
young men.
Eagleman, voice-over: The political agendas around us
actually manipulate the brain activity inside of us.
So is there any way to stop what's happened in the past
from continuing into the future?
One possible solution lies in a 1960s experiment
that was conducted not in a science lab but a school.
Eagleman, voice-over: It was 1968,
the day after the assassination of Martin Luther King.
Is there anyone in this United States
that we do not treat as our brothers?
- Yeah. - Who?
The black people.
Who else?
Eagleman, voice-over: Jane Elliott was a teacher
in a small town in Iowa.
And she wanted to show her class
what prejudice really felt like.
How are black people treated?
They don't get anything in this world.
Why is that?
Because they're a different color.
Eagleman, voice-over: These two men were in that class.
This was Rex back then...
And this was ray.
How many in here have blue eyes?
Ok. How many in here have brown eyes?
Ray, voice-over: Jane says we're going to have
this exercise.
And she right away launches into the propaganda
of blue eyes are better than brown eyes.
Blue-eyed people are better than brown-eyed people.
Eagleman, voice-over: Ray and Rex both have blue eyes.
You brown-eyed people are not to play
with the blue-eyed people on the playground
because you are not as good as blue-eyed people.
Eagleman, voice-over: The brown-eyeds were denied
privileges given to the blue-eyeds,
and they had to wear special collars.
You'll begin to notice today
that we spend a great deal of time
waiting for brown-eyed people.
Do you remember, uh...
What your own behavior was like when you were on top?
I was tremendously evil to my friends.
How so?
I was going out of my way
to pick on my brown-eyed friends
for the sake of my own promotion.
What did you do?
I recall telling Mrs. Elliott, Jane,
that she should keep the yardstick at hand
in case those brown-eyeds got out of control.
I don't see the yardstick.
Do you?
It's down over there.
Hey, miss Elliott, you better keep that
on your desk.
Don't let the brown-eyed people get out of hand.
At that time, my hair was quite blond
and my eyes were quite blue.
And I was the perfect little Nazi.
I looked for ways to be mean to my friends,
who minutes or hours earlier
had been very close to me.
Eagleman, voice-over: But the next day,
there was a reversal of fortune.
Yesterday I told you that brown-eyed people
aren't as good as blue-eyed people.
That wasn't true.
I lied to you yesterday.
Oh, boy...
The truth is that brown-eyed people
are better than blue-eyed people.
Rex, voice-over: A person you trust stands before you
and says, "I was wrong."
Now here's the truth,"
takes your world and shatters it
like you've never had your world shattered before.
You blue-eyed people
are not to play with the brown-eyed people.
Blue-eyed people go to the back.
The brown-eyed people come to the front.
Tell me a little more
about what it was like when you were in the down group.
You have such a sense of loss...
of personality and self...
that it makes it almost impossible to function
with what's going on in the room.
Should the color of some other person's eyes
have anything to do with how you treat them?
No, no.
All right.
Then should the color of their skin?
No.
Should you judge people...
No...
By the color... No...
Of their skin?
No.
Eagleman, voice-over: If I were just gonna riff...
guess at it... it's that, uh,
one of the most important things we learn
as humans is perspective taking.
And kids don't often get
a really meaningful exercise in that.
And when you're forced into understanding
what it's like to stand in someone else's shoes,
that opens up a lot of cognitive pathways for you.
I remember saying something to my dad
about a comment he made, saying,
"no, that's not appropriate."
And it did change within the family.
But you talk about a little kid
making that statement, it's huge.
But it reaffirmed that you could do that...
you could begin to change.
The brilliance
of the blue eyes/brown eyes experiment is
that the teacher, Jane Elliott, switched which group was on top.
And that allowed the students to extract the larger lesson,
which is that systems of rules can be arbitrary.
They learned that the truths of the world are not fixed,
and they're not even necessarily truths.
And this is what empowered the children
as they grew to see through the smoke and mirrors
of other people's political agendas
and to form their own opinions...
surely a skill that we should be teaching to all of our children.
Should the color of some other person's eyes
have anything to do with how you treat them?
No.
Eagleman, voice-over: When people are armed
with an understanding of how propaganda works,
the power of propaganda is reduced.
As we come to understand
the deep importance of cooperation,
we stand a chance not only of reducing dehumanization,
but achieving our potential as a species.
Genocide doesn't have to be the norm.
Instead our fundamentally social nature can hold
the key to our success as a species.
Our future, our survival is
intimately, permanently bound up
with that of the people around us.
Our social drive is at the root
of extraordinary acts of bravery and generosity.
Who you are has everything to do
with who we are.
Our brains are so fundamentally wired to interact
that it's not always clear
where each of us begins and ends.
Our species is more than just 7 billion individuals
spread out across the planet.
We're something more like a single vast super-organism.
Because what your friends know and love as you is
really a neural network embedded
in a far larger web of other neural networks.
In this age of digital connection,
we desperately need to understand
the links between humans.
If we want our civilizations to have a bright future,
we'll need to understand how human brains interact...
the dangers and the opportunities.
Because there's no avoiding the truth
that's etched into our neural circuitry: We need each other.