[MUSIC PLAYING]
Stanford University.
OK, let's get started.
We pick up with aggression,
competition, et cetera.
And where have we gotten to?
We are now just about
to leap to, instead
of early environment,
early hormonal exposure,
parenatal-- hormones both
pre, before and after birth.
Around that time,
what do they have
to do with adult
behavior in these realms?
So, again, this is tapping into
that same concept from the sex
lectures-- organizational
hormonal effects,
versus activational.
Organizational early in life,
setting up the nervous system
to respond later on to some
sort of activational hormonal
effect.
So the basic theme that's come
through with animal studies
here has been built
around, what if you
have females who are prenatally,
or perinatally, androgenized,
exposed to high
testosterone levels?
And what you see is,
basically, the exact same thing
as from the sex
lectures, which is
you get a powerful
masculinization--
organizational masculinization
effect so that later on these
are females who respond
to even their low levels
of testosterone
in the bloodstream
with increased
levels of aggression,
more aggressive play, bunch
of measures like that,
less maternal behavior when
having offspring-- a pretty
clear literature in terms
of prenatal masculinization
of aggressive behavior, as
well as sexual behavior.
So, as usual, what about humans?
And we go back to
our two diseases
from the other week one was that
congenital adrenal hyperplasia
business, that tumor in
the mother that produces
vast amounts of,
among other things,
an androgen, a
testosterone derivative,
which androgenizes the fetus.
Or the case with that drug
DES, diethylstilbestrol,
where some women in
the '50s took them
for preventing
miscarriage, in some cases
had androgenic effect.
Back to the same
issue as with the sex
lectures, so what's the behavior
of these individuals like?
And, again, people
were over that one.
People were really
interested in this.
Both of them kind of
burst on the scene,
congenital adrenal hyperplasia,
and the DES babies,
around the same time
lots of people started
studying these kids as they
started growing up with a very
simple question
here of, are they
going to be more aggressive
than typical girls?
And, ultimately, will they
be more aggressive women?
And somewhere between
the lines, they're
also asking the
question, are they
going to be more aggressive than
is normal for a typical girl?
So what began to come
out of these studies?
First off, some interesting,
odd, quirky things-- one
is when you androgenize
a female fetus
human, later on as
a child she will
have a higher than average IQ.
Whoa, that's kind
of interesting.
Stay tuned, it turns out
that's not at all interesting.
OK, so that was observed.
Another thing,
more of a tendency
towards being left-handed,
better spatial skills.
And both of those
are attributes that
are more common among
males than females.
What else?
That's all that
sort of stuff having
to do with ancillary issues.
But now, finally, people
were then really focusing
in on the issues of aggression.
And by the time these
girls were, I don't know,
10, 12 years old or so, the
findings were absolutely clear.
These kids were way, way
more aggressive than normal.
How do you know?
Because they were less
interested in playing
with dolls than normal
girls, because they expressed
less interest in
marriage, because they
expressed more interest in
having a career some day.
So these were, obviously, over
the top, rabid, psychopathic,
androgenized, females
because they weren't normal.
They weren't interested
in dolls, or marriage,
and were interested in a career.
This was in every textbook
starting in the late '60s,
and was still there in
textbooks by the mid '80s or so,
endocrinology textbooks.
And somewhere in the
early '70s or so,
probably some male
endocrinologists kind of
discovered that,
you know, wanting
a career if you're female
does not count as aggression.
Actually, they came up with an
even better term-- assertive
dominance.
How's that for a term that just
summarizes an entire worldview
of gender differences?
OK, so some male endocrinologist
finally figured that out.
Or maybe actually
they're finally
started being some female
endocrinologists who
pointed out this was gibberish.
The entire literature
went down the tubes,
had to be started all over.
Oh, wanting a career is not
being assertively, dominantly
aggressive if you're female.
So back to stage one on that
whole literature, lots of work
since then.
What the literature
has generally shown
is the left-handedness is there.
The spatial issue
seem to remain.
The higher IQ is there.
What's up with that?
All that's known is
as an explanation,
you find an equivalently
higher IQ in the parents.
So it's got nothing to do
with the androgenization.
There's some sort of
selection going on, perhaps
who winds up being in a study
like this-- sort of more
educated families.
Who knows what.
But that one turned out
to be a red herring.
What about aggression?
Because now there's
been populations
of androgenized girls who
are now well into adulthood.
What about antisocial behavior?
What about all those
sorts of things?
And, in general, what is shown
is there's not much going on.
The literature has
been pretty ambiguous
in terms of any sort of trends
there of different behaviors,
different attitudes, different
motivations, et cetera,
in these folks as they grow up.
But suppose what you
found was, as adults,
women who had been androgenized
as fetuses were now
17 times more likely to
start brawls in bar rooms,
to snipe at people
from the tops of water
towers, things of that sort.
What would you conclude?
Oh, prenatal testosterone
makes you more
aggressive as an adult-- no.
Same confound with these
folks as from the sex
lectures the other week, which
is these girls were not just
born having been exposed to
lots of testosterone in utero,
and doing something or
other to their brain.
They were born with, basically,
a hermaphroditic profile
of genitals that looked
like males, or intersects,
sexually ambiguous genitals.
These were the kids who
went through a dozen rounds
of reconstructive surgery in
their first half dozen years
of life, their first 10 years of
life, in this part of the body
that everyone is interested in,
but doesn't quite talk about.
And what's up with that?
Why aren't I normal?
And these, once
again, were not girls
who grew up with the only
thing being different
about them their prenatal
hormone exposure.
Basically makes the whole
literature uninterpretable.
So what else in terms of
prenatal hormone effects?
Another literature
that people have
looked at, which in
principle could be extremely
informative, looking
at dizygotic twins,
non-identical twins.
So you were a girl.
You're a dizygotic twin.
And you could have a
sibling who is either
a sister or a brother.
In other words, you may have
spent your time in utero
with your sibling who
either did or did not
secrete a certain amount of
testosterone during that time.
Do you see any sort
of masculinization
of aspects of
aggressive behavior
in girls who are dizygotic
twins with a male sibling
rather than a female one?
And what you wind up
seeing is these kids show,
on the average, more
aggressive play in childhood,
more-- here's the
jargony term-- more rough
and tumble play, more interest
in cars, mechanical things
like that, less interest in
stuffed animals, in dolls--
small effect, very small effect.
Nonetheless, it suggests that
this is another realm where
a little bit of prenatal
exposure to testosterone
will change the
behavioral profile.
Except there's a confound
in these studies, which
is if you were a girl and you
have an identical twin who
is a boy, you are in the
Guinness Book of Records.
OK, let's start that one.
If you are a girl and you
have a non-identical twin--
that's how it works, OK.
I knew I should have checked
the notes before coming.
So you've got a non-identical
twin who is a boy.
Not only do you spend
your prenatal environment
being awash in some of
his dribbling hormones,
but you grow up with him.
And girls who grow up
with boys as brothers-- as
opposed to plants as brothers.
Whoa, what is happening here?
OK, being a girl growing up
with brother brothers increases
the likelihood of rough and
tumble play, because that's
what you do with your
brother-- once again,
uninterpretable literature.
Generally, what you
see is very, very clear
cut androgenization of
aggressive behavior prenatal
testosterone when you're
looking at rodents.
By the time you're looking at
primates, some pretty strong
patterns but nowhere near
as dramatic as in rodent
species looked at.
By the time you look at
humans, maybe just some hints,
but that at the most.
Of the most interesting
realms, literatures,
where people have been thinking
about prenatal testosterone
exposure is work
of a guy in the UK
at Oxford named
Simon Baron-Cohen.
And what he is, is basically
the world's expert on autism.
And he has developed what
is called the hyper male
hypothesis of autism.
For starters, there's a
very, very big gender skew
in autism-- far more frequent
among boys than girls,
among males than females.
And what Baron-Cohen has done
a lot of work on over the years
is first looking
at a whole array
of sex differences between
normal human males and females.
Sex differences, some of
it's the finger ratio stuff.
Some of it is
neural anatomy, some
of those structural
differences in the brain,
having to do with that.
Some of it is functional spatial
skills versus language skills.
Some of it is problem solving.
And there is a gender
difference that
tends to come through with that
on the average in that boys,
males, men, take more
analytical approaches
to social problem solving.
Girls, women, females,
take more empathic ones.
So that's a difference.
OK, so he studied
all sorts of stuff
like that, and obviously
with hormones as well--
all sorts of really subtle
interesting physical
differences, whole
array of these.
And what he has shown is
that individuals with autism,
regardless of their
sex, tend to have
even more exaggerated
versions of
those male typical
profiles-- the finger length,
the analytical focus at
the cost of social empathy,
social affiliation, the
very strong spatial skills,
whole bunch of those.
So he's made a fairly
convincing argument,
I think, that is good.
Something's going on in terms
of prenatal androgenization,
perhaps, which produces a more
masculinized profile, which
taken to its extreme
winds up being autism.
In other words,
normal male behavior
is just skating on
thin ice before going
into this whole realm of sort
of dysfunctional socialization.
Lots of stuff with
that, as we'll
see next week some very
interesting differences
in the wiring of the cortex
of people with autism.
And males show that same
thing, just not as extreme.
OK, interesting footnote
thing-- Simon Baron-Cohen
is apparently the cousin of
Sasha Baron-Cohen of Borat,
which suggests that must be one
interesting family when they
get together for the holidays.
OK, moving back one
more box, however-- no,
I'm not going to do that.
OK, moving back one more box.
Now, instead of
perinatal hormone stuff,
early environment,
what about genes?
What about genes?
What do genes have to do
with aggression, competition,
cooperation, empathy, et cetera?
It used to be not that
long ago if you even raised
the possibility that there were
genetic elements to aggression,
you would be hounded
out of certain realms
of social science.
It was viewed as wildly
incorrect, wildly offensive,
hidden agendas out the wazoo.
For some reason, this began to
pass in the early '90s or so.
There were studies in
the mid '80s, conferences
in the mid '80s, where
there were protests.
They were picketed, because
in this meeting that
was considering the
sociology of aggression,
the this of aggression,
the biology,
the genetics, the
inclusion of it,
was the grounds
for the picketing.
A number of those were canceled
by the National Institutes
of Health under public pressure
of certain interest groups, all
of that.
It used to be viewed as
outrageously offensive,
the notion that genes have
anything to do with aggression.
So there's two ways of
showing that that's wrong.
The first is to
sit somebody down
and make them go through the
last 15 lectures in this class.
Or the other is to
reflect on the fact
that you would leave
a three-year-old
in the care of a basset hound,
but not with a pit bull.
Oh, there are breed-specific
differences in behavior.
That, if nothing else,
is a demonstration of it,
that dog breeds have been
bred for 20,000 years or so
to differ in levels
of aggression,
in levels of
affiliation, all of that.
People who for some bizarre
reason follow bullfighting,
there are lines of bulls,
different ranches of Spain
in Mexico, where
they have been famous
for centuries for the particular
fighting style of the bulls
that they breed.
Genes have something
to do with it.
Of course they do,
because hormones
have something to do with it.
And because receptors,
and because enzymes,
and everything with that, it
is impossible to have talked
about any of this stuff on
the far right of the chart
without invoking genes--
a ludicrous view.
So what is known about
the relevance of genes
to aspects of
aggressive behavior?
First off, at this
stage, there's
been a whole bunch of studies--
many of them winding up
in some very visible
journals-- where people find
a gene implicating it in
abnormal levels of aggression,
one of those sorts of behaviors.
Typical strategy-- these might
be genetically engineered
animals to remove that gene.
Or there might be a
spontaneous mutation.
And all of these
report that these
are animals with a whole
bunch of these mutations,
that these are animals
with abnormally
high levels of aggression.
That's kind of a
clean experiment.
If you go in-- and thanks to
a mutation, or chopping out
one particular
gene, and now you've
got a lot more aggression
in that individual.
That kind of suggests
that that gene
has something to do
with aggression, perhaps
a whole lot.
What are all the
problems with that?
Other ways that
that gene could be
affecting behavior,
which indirectly winds up
getting to aggression.
One possibility-- what
if that's a gene that
is relevant to impulsivity?
And this is an
individual who, if you
gave the mouse a
different realm of tests,
would be shouting its love
to the world at an impusively
high rate, just as
it's being aggressive
at an impulsively high rate.
Maybe it's a gene having
to do with impulsivity.
Maybe it's a gene having to
do with one of the things
we heard in the last lecture.
What are the environmental
releasing stimuli
that cause aggression to occur?
What's one of the
most reliable ones?
Pain.
Oh, it turned out a
number of these strains
of mice that were identified
with a gene knock-out.
That here's a gene which
can cause aggression.
It turned out that
these were genes
that made animals that were
much more sensitive to pain.
And they were more
likely in a pain state
to displace aggression
on to something else.
Or, as was shown
in some of these,
these were animals who
were more aggressive.
But they were also
more affiliative.
And they were more everything.
Their generic level of
arousal was a lot higher.
So all these caveats, an
awful lot of the genes
that popped up in the first
generation of those sorts
of studies that looked
solid, that were replicated,
a lot of them instead had
to do with indirect routes,
rather than directly
with aggression itself.
So what about the genes
that have held up?
And in the really
plausible candidate ones,
we've covered some of
these are already--
the serotonin synthesis genes,
and the serotonin receptor
genes, and the dopamine
receptor genes.
All of those have been very
solidly implicated, really
careful research, the
molecular biologists teaming up
with behaviorists
knew what they were
doing-- a genetic component.
And what you know by now
that is absolutely about
is this figure again.
That's the case with
all of these genes.
Oh my God, it's not
genes causing aggression.
We know exactly this
one, modulation,
all that stuff, again
depending on the environment.
And the environment
in the realm of genes
relevant to aggression,
the environment
is overwhelmingly about abuse
and stress early in life.
So that's about as far as
genes will get you there,
which is plenty
good, because this
is exactly how the genes
should be relevant to behavior.
This is how all genes
are relevant to behavior.
Remember our ultimate punchline
from the behavior of genetics--
at the end of the
day, it actually
doesn't make any sense to
ever say what any gene does,
only what it does
in the following
range of environments.
In terms of that, what
you are beginning to find
is this still sort of
growing field which
is beginning to look at
differences in these genotypes,
these different
versions of these genes,
in different populations,
in different cultures.
And that's just beginning
as a literature.
I'm not impressed
enough with the findings
yet that it's worth
passing them on.
But that is going to be
a very interesting field.
Finally, there's always this
puzzle with any of these of,
oh, you've got some gene
that's predisposing you
towards being aggressive if
you were abused in childhood.
We still know nothing
in terms of that gene.
That gene has got
no predictive power
as to whether this will thus
be someone who grows up and is
a sociopathic murderer.
Or if this is someone who grows
up and is just an unbelievably
nasty Monopoly player.
That factor, again,
that same deal-- oh,
major frontal cortical
damage, disinhibition.
You can't regulate
your behavior.
No science in terms of
the neurobiology as to why
one turns into a serial
murder, and the other one who
doesn't catch clues that the
family wants to eat dinner.
Again, it's the same
puzzle over and over.
And, again, you could begin to
guess what the differences are
going to be.
Problems in some of these realms
with these aggressive genes,
and different upbringings,
different stabilities
and families, different
relationships, different role
models, you can be off
and running with that one.
One final domain in
genes and aggression--
and only a handful of
you the other lecture
knew who that guy
Charles Whitman
was, who was the
guy who climbed up
the Texas tower, all of that.
OK, so here's another
chance to score points
in the mass murderer realm.
How many people have ever heard
of a guy named Richard Speck?
Wow, very few-- no hands.
OK.
No, that's a bottle
going up, not a hand.
Richard Speck was once one
of the most notorious people
in America.
Richard Speck was a
nightmare sociopath
who in 1968 committed
a crime that just
stunned the entire country.
People wrote songs about it.
It was just as brutal
as one could imagine.
He broke into the
apartment of eight nurses
living in Chicago,
eight student nurses,
and slaughtered them all.
And this was shocking on a
level that's hard to describe.
Richard Speck was the
nightmare sociopathic murderer.
So he gets sent off to
prison eventually for life.
And in the process at
some point or other,
he's getting some physical exam.
Somebody takes a blood
sample something.
And a lab technician
notices something
interesting in his
blood, examining
the chareotypes, the
structures, of his chromosomes.
And they discovered that
he had an extremely rare
chromosomal abnormality.
Females, XX, males,
XY-- every now
and then you get somebody
where something screws up.
And what you now get is XYY.
You get an extra Y chromosome.
And, suddenly, this had
to be the explanation
for what was going on.
Males are a total pain in
the ass all over the world.
And they've got
those Y chromosomes.
Oh my God.
The guy has two Y chromosomes
in every single cell.
This explains it.
And this suddenly
started this hysteria
about violence and the XYY male.
Senators were
bellowing in Congress
about how we needed to screen
our schoolteachers to make
sure none of the men
had XYY profiles.
The military was all set to
start testing recruits for XYY.
Although it's not clear if
that would get you in or would
that get you out,
how that one worked.
But they were
suddenly interested.
Tons of work went
into it, this flurry
of excitement, special funding.
We need to be on top of this.
And by the early '70s,
what was clear was
there was no
relationship whatsoever.
So that one went down the tubes.
And then one of those
ironic ending departments,
it was eventually discovered
that a lab technician had
blown, had done the
chareotyping wrong.
And he really
wasn't an XYY male,
despite that lab technician
then having called up
the newspapers.
He was a normal XY
sociopathic male.
So that one was up
there for a while,
more realms of don't overvalue
the genetic evidence.
So that shifts us now
one step further back.
And now begin to look
at whole populations--
whole populations not yet on
the genetic evolutionary level.
But what do things
like ecology have
to do with levels of aggression?
What does culture
have to do with it?
What does factors like that?
And there's a really interesting
array of findings out there.
First off, one
important dichotomy
when looking at
traditional human cultures
is how people make their living.
And the one that's
pertinent here
is the dichotomy between
pastoralist people
and everybody else.
Pastoralist people, nomadic
pastoralists people, these
are cow people.
These are people who wander
around with their goats,
or their camels.
These are the
shepherds, in contrast
to traditional
agriculturalists, or far rarer
traditional hunter-gatherers--
so nomadic pastoralists
versus everyone else.
And what a boatload of
anthropology has shown
is nomadic pastoralists have
higher rates of violence
both within group
and between group.
Nomadic pastoralists are vastly
more likely than other groups
to have standing
armies, warrior classes,
to have leadership be
derived from people
who have had the most
success as a warrior,
to have myths built around their
religion that success in war,
violent acclaim in war,
is your gateway to heaven,
or whatever afterlife is
viewed as most desirable.
This is a consistent finding.
Lots and lots of these
cultures, nomadic pastoralists
are the ones who came up with
warfare on a certain level,
and warrior classes.
And this makes perfect
sense, because one feature
of being a nomadic
pastoralist is you're nomadic.
At certain times of
the year, there's
one subset of the whole
village who's off 15 miles
away where there's
some good grazing.
Another group is
on the other side.
And what this sets you up for
is something that farmers never
have to worry about.
Somebody can't come and rustle
your farm away at night.
But people can come and
steal all your animals.
Warrior classes, so
that at any given point,
if people are dispersed, there
is still a designated age group
of individuals who are out there
to defend the collective herds
of the group.
So you see that.
In the United States,
where that has had
an interesting
manifestation is where
people settled in the
original 13 colonies,
from which part of
the United Kingdom.
And some very influential
studies, really interesting
creative ones, pointing
out that the American South
was disproportionately
settled by sheep people
from the northern ends
of the British Isles--
in other words,
nomadic pastoralists.
Shifting to another realm of
anthropological designation,
these are people who
disproportionately have
come from cultures of honor.
Cultures of honor,
where people are
willing to kill over very
symbolic slights rather
than over material
conflicts, where there
are vendettas within
the group, there
are vendettas
between groups, where
it is honorific
to have to avenge
a death, which you
do not necessarily
find in agriculturalists.
Cultures of honor, and
that goes hand-in-hand
with nomadic pastoralism.
And what you get
there, typically,
are very clear rules
about enforced hospitality
for guests, and very clear
rules of the circumstances
of aggression, retributive
ones, over symbolic affronts.
And that's really clear
difference regionally
in this country.
Interesting sociologist,
University of Michigan,
named Richard Nesbett.
And he grew up in the South.
And I actually heard
him once give a talk
where he talks about how
when he was about 18 or so,
he left the South
for the first time
and joined this very
strange culture at Harvard
University as an undergraduate.
And he was dumbfounded by how
different of a world this was.
People didn't shoot
relatives at picnics,
at barbecues, which
sounded totally facetious.
But when you look
at the higher crime
rates in the American
South, it is not
occurring in urban areas.
Urban crime is
roughly equivalent
all throughout
the United States.
It is not due to
higher rates of what
they call 7-Eleven robberies,
which is just material
gain, a robbery of that sort.
It is murders of honor.
It is people who know each
other at social settings,
people who have some insult,
have something that has nothing
to do with material wealth.
This is where the
disproportionate violence comes
from in the American South.
And prompted by
that, Nesbett did
one of the all-time interesting
studies, this famous, amazing
study.
So he's at the
University of Michigan.
And he recruits
student volunteers
who believe they're going
in to do a hopscotch test,
or some such thing.
And they're going in.
But he made a point of finding
out where everyone came from.
And he got a fairly
even distribution
between the relatively
few students in Michigan
from the American
South, and then students
from the more traditional North.
So we get into the psych
building, each individual who's
coming for their appointment.
And they take the elevator.
And they come out.
And they walk down the hall.
And this is where the
experiment happens.
Nesbett has somebody
working on the project--
a confederate on the project,
I say making a lame pun, OK.
So a confederate on
the project, a person
working on the project.
And this was a big, beefy guy.
And the whole idea was
that this big, beefy guy
was going to do
something insulting
to this individual walking
down the hallway, all male.
Here's what they did.
They clearly did
a lot of thinking
in designing this study, in
terms of what single word
this person was going to say.
And this is what
he wound up saying.
The volunteer would be
walking down the hall.
Here comes this big,
beefy guy moving fast.
And as he comes by him, bumps
into him with his shoulder,
walks past, and says, watch it,
asshole, and then disappears.
Volunteer comes in
to start their study,
and quickly they look at blood
pressure, and heart rate,
and stress hormone levels,
and testosterone levels,
and get a typical participant
in this study from the North.
And they come in.
And they're a little bit
irritated, and what a jerk,
and all of that.
And it's all over with
two minutes later.
Get people from
the American South,
on the average massive stress
response, hypertension,
elevated testosterone levels,
big regional differences.
These are some of the
physiological pictures
of cultures of honor.
What else?
What other interesting things
about ecosystems, or ecology,
or cultural aspects?
Another dichotomy that is
really consistent-- and this one
maps pretty readily on that
pastoralist versus everybody
else-- the sorts of cultures
and the level of violence
that are generated
in cultures that live
in deserts versus rain forests.
And, once again,
deserts are where
you are far more likely to
find nomadic pastoralists, rain
forests, hunter-gatherers,
mixture of hunter-gatherers,
small farm agriculturists--
two totally different worlds
of occupations.
And what you see
is far higher rates
of violence within
group and between groups
in desert dwellers.
And that maps very
logically onto pastoralists
versus everybody else.
Desert dwellers, open
savanna grasslands,
that's where you see
the warrior classes.
That's where you see
raiding of other tribes.
That's where you get that
pattern, virtually none
among the hunter-gatherers.
I might point out
something which
will become sort of focused
on more in a lecture in about
a week or so.
I should point out that desert
dweller nomadic pastoralists
are also the cultures
on this planet that
invented monotheism.
Consistent difference--
desert dwellers
tend more towards monotheism.
And it was invented by
desert nomadic pastoralists.
Rainforest cultures
far disproportionately
tend to be polytheistic.
And this is not
remotely surprising.
If you're living in a
rainforest and there's
10,000 different types of
edible plants around there,
it doesn't take a lot of work
to come up with the notion
that there's lots of different
spirits and gods out there.
What the desert it is about is
one, singular baked truth there
of surviving.
That's where
monotheism was born.
Monotheism,
historically, is more
associated with cultures that
invented warfare, and invented
warrior classes, and raiding,
and things of that sort.
That's kind of interesting.
OK, moving on, more cultural
differences-- one of the great,
great predictors of having a
society with lots of violence
in it, and lots of
warfare elsewhere,
is a culture that has
rots of cultural myths
of victimization.
We have been screwed
historically, because of this,
this, and this, and coupled
with that an ethos of not
turning the other cheek,
but instead of retribution.
Cultures that have
strong histories
and or myths of victimization,
and strong values
built around retribution are
extremely violent societies,
and often really bad
news as neighbors.
What else?
Amazing study that got
published about a year ago,
which is on the
recommended reading list.
This is not required.
But this was a deeply
interesting study.
It
Was one of those
game theory studies.
It was a game a little
bit like prisoner's
dilemma-- not exactly the same,
but the same sort of notions
that you could be very generous
in your game playing style.
You could be absolutely
rationally fair.
You could be exploited, a
whole range of possibilities.
What these guys
did in this study
was take scads of people
from 40 different countries.
No they didn't,
from 16, 19, they
took from a bunch of
different countries.
And just to control for
things, all of the subjects
were university students.
So you're selecting for a
fairly homogeneous bunch,
both within group and across
these different countries.
And what they did was they
had people play these games.
And they had the option for what
is called altruistic punishing,
which we will hear more about
in a little while, which is you
have the option to expend
some of your resources--
your points, your
chips, whatever--
you can spend to punish the
other individual for cheating.
And the question,
of course, becomes,
how much are you willing
to spend to punish somebody
when they've been
cheating against you,
when they've been stingy, when
they haven't reciprocated,
all of that?
First finding,
which is everybody
across all the
countries averaged out
to the same rate, the
percentage of resources
that someone is
willing to expend
on punishing a cheater-- so no
particular cultural differences
there.
But then they identified
another interesting realm
of game behavior here,
which they called antisocial
punishment, which
is where it's not
that you are expending some
of your resources to punish
somebody for having cheated.
It's where you're
expending resources
to punish someone for
having been overly generous.
And that pops up in
certain sorts of games.
It is not terribly
common when it's
the person who is choosing
with their opponent.
But when you have
a third party, you
have no cultural differences
at the rate at which they
are willing to punish cheaters.
But here's where
the differences came
then, the rate at which
people would punish
unexpectedly generous players.
And you got a big spread.
The lowest rate at
which this happened
was, nicely, as it
turned out, people
from this country, which is kind
of nice, people from England.
And, of course, who else?
The ever-useful Scandinavians
with their powerhouses
of the cells and their
other cliches all set.
So the Scandinavians
come through yet again.
But, for once, we're able
to hang out with them
and actually count as
having a good profile--
the lowest rates of
people being willing to do
this nutso anti-social
punishing in those countries.
In between rates-- a number
of Middle Eastern countries,
a large number of Eastern
Bloc countries, in other words
Slavic ones that used to be
part of the Soviet Union, Korea,
and turkey.
Those were the middle ones.
Which ones had the worst rates?
I will just read the
two countries here
that were way up there,
a big gap between them
and the rest of the countries.
One was Greece.
And the other were the Arabic
Emirates on the Saudi Arabian
Peninsula, where people
are willing to spend more
to do anti-social
punishing than they
are willing to spend
to punish cheaters,
extraordinary finding.
People from Muscat, which
was where the university was,
those students were more
willing to punish someone
for being unexpectedly
generous than for somebody
cheating on a game theory social
contract-- totally amazing.
So what's that about?
When they actually
question people,
you see things with
people from there
along the lines
of, if people start
doing that, of being
all generous like that,
it's just going to up
the ante for everybody.
Everybody's going to
have to start doing that.
That's an interesting
piece of reasoning.
But when you look at a larger
level, what these researchers
then showed was a
predictor across all
these different
societies of the rate
of this anti-social punishment
levels of trust in the society.
Some standard metrics
used by sociologists
who were interested in this
concept of social capital--
how much social trust there
is in the society, how
much participation there is,
how much of a sense of efficacy.
And what you see is
the lower the levels
of social capital
in these societies,
the higher the rates of this
anti-social punishment, totally
interesting study.
Next in the realm
of culture, what
are people doing
these days, what
is sort of the science and
the research these days,
trying to make
sense of terrorism,
and the sort of cultures
that give rise to them,
and the sort of ideologies
that give rise to them?
A number of basic
dichotomies-- one
is a camp that
views it as always
abnormal sociopathic behavior.
Another is a camp that
just views terrorism
as extremes of ideology.
The first one is much more
about individual dysfunction--
oh, this is a neuropsychiatric
problem, perhaps.
The second one is
one more a feature
of cultures that have
extremely strong ideologies.
So that's one division in
there as to how to think
about it in the community.
Another division is
really interesting.
And it's one my reading
of this literature
that has totally thrown people
in the field for a loop.
Forever, there has
been a profile,
a demographic and
psychological profile,
of individuals who
are terrorists,
all the way back to the
people who did the Boston Tea
Party in this country, the IRA.
All sorts of stuff like
that, the Haganah, which
was in Israel, terrorist
acts before independence,
studied in a whole
bunch of these
that there tends to be a
rather consistent profile
of these individuals
who would be terrorists.
Young, male, socially isolated,
socially unaffiliated in terms
of relationships, relatively
uneducated background,
history of childhood abuse, and
another factor which has just
completely slipped my mind.
What was it?
Oh you all know.
OK, so that's exactly what
you find in these folks--
a picture of isolated
sociopathic individuals
who already have a history
of anti-social behavior.
These are people who,
if they hadn't stumbled
into this cause,
would be spending
their time mugging old ladies.
That would be that profile.
And you look at
these various groups.
And that has been
a consistent one.
Terrorism in the recent years,
particularly Middle Eastern
fundamentalist, is a
completely different profile.
It is not young men.
It tends to be educated,
well-off people
in their thirties and forties,
overwhelmingly middle class
or upper class backgrounds.
Next, it's not just
middle-aged males.
It's females.
It's women to a much
higher extent than seen
in any previous
sort of population
dealing with terrorism.
Next what you see is
these are individuals
who, on the average,
tend not to have
had any direct exposure
to the suppression
that they are fighting against.
As opposed to the sociopathic
model, a classic picture
with IRA gunman, the father
was taken away by the whoevers,
shot, never came back again.
And they were passed
on the family mantle.
The current picture is
a very different oe--
no direct experience
of the persecution.
Finally, tending not to have
particularly high levels
of religiosity, and this is
this very contemporary profile
where you get these 40-year-old
engineers who are suicide
bombers, where they go home.
They say goodbye
to their families.
They make a video tape sort
of wishing everybody well.
And after having quit their
job and paying the rent one
extra month, and off they
go and blow themselves up.
People, I sense, in the
field haven't a clue
how to make sense of what
this is about, very new,
challenging feature.
One interpretation,
one is of a school
pushed by people
like Phil Zimbardo
here in the psychology
department, incredibly
influential psychologist, who as
a general theme over the years
has argued for the stance that
under the right circumstances,
under the right
coercive circumstances,
virtually anybody could do
anything that is appalling.
Zimbardo, who did the famed
Stanford prison study.
The other view is, OK,
this isn't a lesson
that anybody could wind up being
this violent if, look at them.
They're an engineer.
And they've got a master's
degree, and all of that.
Instead, it is simply an outcome
of a lot of what terrorism
is about these days,
a very novel world
of international terrorism.
Rather than within
country, suddenly you
have a world of people who
need to be able to do things
like get passports, and
fly elsewhere, and be
able to navigate customs,
and things of that sort.
It is suddenly selecting for a
more sophisticated population
of individuals.
You know, the jury's
out on all of this.
But this seems to be a
very challenging thing
for that field.
OK, so now this allows us to
push one step further back.
I'm going to skip over
a few things there.
Now, insofar as we are
looking at culture,
and insofar as we have looked
at anthropological differences,
and insofar as we have
looked at anything having
to do with genes, we now
have to talk about evolution,
because that's where the
genes came from, of course.
So in first pass,
it's absolutely simple
to understand what evolution
has to do with aggression, which
is evolution selects for higher
and higher levels of aggression
because that's what
you need to succeed.
Unless you grew up watching
certain types of television
programs, in which
case evolution selects
for no aggression
occurring because animals
behave for the good
of the species.
So sorting through
that, beginning now
to apply some of our
foundations from that world,
individual selection, kin
selection, reciprocal altruism,
and the modern version
of group selection.
So where do these play out?
First, how do these
play out in terms
of increasing the likelihood
of aggression and antisocial
behavior?
Individual selection, males,
that is absolutely simple.
In every culture on this
planet, and in the vast majority
of social species that
have been looked at,
the majority, the major
cause of aggression
in that society or species
is male male violence
over reproductive
access to females.
That is close to a universal.
That is the most
common form motivator
of violence on this planet,
humans and otherwise.
So that one's easy
to come up with,
in terms of obvious stuff.
One classic study,
insanely controversial one,
that appeared to be the
landmark demonstration of some
of the same in humans--
traditional tribe,
hunter-gatherer down in
Venezuela in the Amazon
called the Yanomamo
who have been
the darlings of high
testosterone male
anthropologists for decades.
These have been intensely
studied people, many decades
now, predominantly by
an anthropologist named
Napoleon Chagnon, who is now
emeritus at Santa Barbara.
But he has been a major
figure in anthropology
for a long time.
And these people are insanely
aggressive, incredibly high
rates of violence between
groups, within groups.
Sufficiently so that
the written monographs
of the Yanamamo, with
titles like Yanamamo,
the fierce people,
things of that sort.
And about 15 years ago,
Chagnon published a paper
in Science using
decade's worth of data
showing that the more people,
particular men in this society,
in this tribe, the more people
you have killed on the average,
the higher your
reproductive success
That's it.
That's it.
That's everything right there.
That's Darwin all
over the place.
Just play it out over time.
And this is dramatic selection
in a traditional human society,
the reproductive rewards
of violence and murder.
Very major, influential
study, picked up
by all the newspapers.
And it has been completely
mired in controversy
ever since, all sorts of
ethical attacks on Chagnon,
most of which that
have not stuck,
but some really, really telling
dissections of the work,
ripping it apart on
statistical grounds.
I don't think it's
actually for real.
But that as easily interpreted
within that framework.
Then more realms of violence,
individual selection,
orangutans raping each,
rape in other species,
rape among humans, which
of course brings up
the question of whether
rape is more about passing
on copies of your genes, or more
about power and subjugation.
And the overwhelming
sense in the field
is it's about the latter.
It does not have a whole
lot to do with a world
where you have to start counting
numbers of copies of genes,
and thinking about
adaptiveness of strategies.
Next, individual selection,
explaining another realm
of violence-- in most
cultures, and in an awful lot
of species looked at, the
second leading cause of violence
is males attacking females
over denial of sexual access.
And this is amazingly
common all over the place,
the second leading
cause of violence
on this planet across humans
and different cultures,
and obvious easy individual
selection explanation there.
Finally, another realm
individual selection,
the world of female
female competition,
and infanticide,
competitive infanticide.
We know how to run all of those.
So lots of reasons
within the framework
of individual selection
to see where you are
increasing rates of aggression.
Next, kin selection-- you're
going to know that one as well.
Two brothers or eight cousins,
and that whole strategy,
and that's why
related individuals
cooperate with each other in
circumstances of aggression.
Chimpanzees--
chimps are function
where females are the ones
who pick up at puberty
and go elsewhere.
So all of the adult
males in a chimp group
are brothers, first cousins,
things of that sort.
And, thus, you get
one of the outcomes
of that, high levels of
male male cooperation.
And as we heard, that has been
reported by Goodall and others
to result in things
that look absolutely
like organized
warfare and genocide,
eradicating all the males in
a group in the next valley
over, purely along
kinship lines.
What else?
Other primates, old world
primates, monkeys like baboons,
aggression is very much
between lineages than within,
same exact kin selection
sort of arguments.
So what happens when
you get to humans?
Things get more
complicated, of course.
The first one being that
a relative, relatives,
is a relative term, in
that it is a sliding scale.
Wonderful quote to that
effect, a Bedouin quote,
which is, it's my
brothers, my cousins, and I
against the world.
And it's my brothers and
I against my cousins.
As in, who counts as an
us, and who counts as a
them is a sliding measure.
It is a relative measure.
What you see is by
the time you get
to humans capacity for very
rapid shifts of us/them
along the lines of relatedness.
Now, one of the readings,
which I can't remember now
if I actually did stick
into an assignment,
but one of the readings looks
at the classic social biological
interpretation of making
sense of aggression
along the lines
of kin selection.
What do you make of child abuse?
What do you make of homicidal
parents, damaging parents?
How do you make sense of that
in a, are you out of your mind?
This is copies of your genes
there, the challenges to that.
And this is a couple, Daley and
Wilson, University of Toronto,
I think, who have for
decades been working
in this area showing
things like a child is
more likely to be
abused by a stepfather
than a biological father.
Wonder what that's about?
Kin selection, that's easy.
A child is more
likely to be abused
by a paternal grandparent
than a maternal one.
Kin selection explanation--
more certainty of paternity
when something is going
through a female line.
So they've been
all these studies
showing that degree
of relatedness
explains a fair amount of
the variability in patterns
of violence within families.
Problems with it--
two problems, one
is there's been a lot of
failure of replications
in other societies.
The Scandinavians, for
example, don't see that pattern
when they study it.
The other is there's
alternative models.
There's economic
models, for example.
When times get tough in
terms of displacement,
family violence increases.
Families with stepfathers,
on the average,
are under more economic
duress than families
with biological fathers, greater
likelihood of violence there.
It is a very
uncontrolled literature.
That is sort of viewed
as in the classic,
and in other people's view, the
most ideologically most extreme
way in which social biologists
think about something as
bizarre and challenging as close
relatives killing each other.
One final realm, which is in
terms of this us/them stuff,
the point here being, how do you
decide who is an us and them?
And suddenly, we're in
our world of ethology.
Do we make some us/them
dichotomies more easily
than others?
Do we have prepared
learning to see
some differences as more
salient than others in us/thems?
That remains an immensely
controversial subject
in terms of what are the natural
categories that young kids
divide people up by?
Are kids colorblind in
terms of skin color?
Are kids blind in
terms of body types,
in terms of some such things?
Lots of work in this
area, how unnatural
are some of the
us/them dichotomies
that we tend to come up with?
Stay tuned about 20 minutes, and
you will see not very natural
at all.
As soon as you get to humans,
all this social biology
stuff with kin selection
is interesting, but as
soon as you get to humans you
get to something vastly more
interesting and important.
Back to our recognizing
relatives realm--
the business of how we interact
not with our relatives,
but with people who we
feel as close to as if they
are relatives-- pseudo kinship.
And what you see in
culture after culture
is brilliant manipulative skills
on the part of powers that
be to make some non-relatives
feel more related to each other
than they actually are.
What's this about?
This is military indoctrination.
The whole point, or
one of the main points,
of military training
early on is to get
people to become a
band of brothers,
a band of pseudo
kinshipped relatives,
to increase the
cooperativity later on,
to increase the
odds that you are
willing to give up your life
for the person next to you.
Culture after culture
is great at doing this.
Warrior cultures-- for example,
the Maasai in East Africa,
they have a warrior
stage when you're 15,
you go become a
warrior, roughly 15.
And you stay that
way for a decade.
And you protect the cows.
And you raid the neighbors.
And once you're 25,
you become an elder
and get married then
to a 13-year-old.
But what you've got there is
the entire structure of warrior
life is built around
pseudo kinship.
They live separately
from everybody else.
They use kinship
terms for each other.
For the rest of their
lives, their wife
will refer to somebody
from their warrior class
as her brother-in-law.
Warriors are not allowed
to eat their own food.
They can only share their
food with another warrior,
all built around
generating pseudo kinship.
Other version, that other
more industrialized version,
the Israeli Military,
for example,
allows kids when they are
signing up after high school
to join particular units as
a group, a group of friends
from their high school,
increasing the pseudo kinship
element there.
More of that-- something that
was absolutely unprecedented
when you look at the difference
between kinship and pseudo
kinship.
World War II, United States
hugely heterogeneous country,
obviously, blah, blah,
melting pot, all of that.
And World War II was sort
of the peak of that picture.
And what you got in
many, many fighting units
was something straight
out of central casting
in these inspirational movies.
There's McCarthy from Boston,
and Sapiola from Philadelphia,
and Kewalski from Chicago,
and then the Southern guy,
and the Jewish guy
from who knows where.
And they're all together.
And they're a fighting
unit of American unity,
and all of that.
And what does that produce?
Something that was virtually
unprecedented in warfare.
If you were an American
soldier in World War II
and you were of German-American
or German ancestry,
you would, on the
average, almost certainly
share more genes in common
with the people you were trying
to kill than the people
you were willing to give up
your life for, as you had
classically heterogeneous
troops on the American side--
completely unprecedented,
so this business
of pseudo kinship.
Historically, Vietnam
was apparently
a major failure of military
pseudo kinship mechanisms,
in that something
unprecedented was done there,
which was people were not
kept in stable fighting units.
Instead, people were constantly
shuttling in and out.
And you would get these nutty
circumstances, apparently,
where you'd be there in the
middle of the firefight.
And the person over here is some
kid who showed up this morning.
And the guy here,
if he survives this,
he's shipping out home
to Hawaii tonight.
And who feels like a brother?
No one.
Vietnam had an unmatched degree
of breaking of unity of troops.
Why was that done in Vietnam?
Something that kept happening.
As soon as they allowed
units to remain more stable,
the rates at which soldiers
were shooting their officers
would go way up.
So another, perhaps,
version of cooperation.
Hand-in-hand with
the pseudo kinship
is, of course, the flip
side, pseudo speciation,
the mechanisms, the
psychological, the propagandist
mechanisms that are available
to make them seem as
different from you as possible.
Not just different
sorts of people,
but pseudo speciation-- they
are so different they hardly
even count as humans.
It doesn't count as
much when you kill them.
And endless realms of that
World War II propaganda
in the United
States about various
ethnicities that
we were fighting
against pseudo speciating,
various genocides, the Rwandan
one.
The sort of call to arms there
was kill the cockroaches,
kill the cockroaches, the
Hutu tribes killing the Tutsis
there.
And this was pseudo speciation.
Let me give you an
amazing example which
occurred in this country not
all that long ago around 1990.
An astonishing piece
of pseudo speciation
that happened in this
country-- 1990, first Gulf War.
Kuwait was drilling oil from
underneath the Iraq's land.
Iraq got pissed
off, invaded them.
And, suddenly, we had
the first Gulf War.
The United States goes in
there to drive the Iraqis out
of Kuwait.
And ultimately has
to make the decision
of whether to follow them
into Iraq and overthrow
Saddam Hussein.
And that wasn't done.
But so this war going on.
Very early on, it
was absolutely clear
where it was heading, which was
that the diplomacy was failing.
And the United
States was beginning
to pull together a coalition
of various countries
that would be a unified
force fighting against Iraq.
But it had not yet been
authorized by US Congress
as an act of war.
Suddenly, into
this came a woman,
a refugee from Kuwait City.
Refugee, she was a nurse who
worked in a hospital there.
She had managed to
get out of Kuwait
after the Iraqis had invaded.
And she came and
testified in Congress
about an appalling thing
that she had witnessed,
which was when the Iraqis
came in and took over
their hospital, not only did
they steal all the supplies.
They took the newborn
infants out of the incubators
and left them out to die, and
shipped the incubators back
to Iraq.
Everyone was
flabbergasted by this.
This was every newspaper
in the country, everybody
learned about this.
Everybody suddenly learned,
my God, they leave babies out
to die.
These people hardly
count as human.
And, critically, that war
was authorized by Congress
by just a couple of
votes of senators.
And at least a
half dozen of them
cited this incident in helping
them decide and this was
something that had to be done.
This was a deciding factor
in us going to that war.
And the remarkable thing
is, it never happened.
The nurse was not a
nurse from Kuwait City.
She was the niece of
the Kuwaiti ambassador
to the United States.
She had been trained
by a public relations
firm paid for by
the US government
to make up this story.
And she sat in our
Congress on live TV
in front of the entire
country, lied like crazy.
And we went into that war
with a 92% approval rate-- one
gigantic piece of
pseudo speciation.
My God, they leave
babies out to die.
It will hardly
count killing them.
They're hardly even human.
And the coverage of when it
was revealed what was actually
going on with this person
didn't come anywhere close
to front page in any newspaper
in the country, buried down
in there.
Virtually the entire country
came out of that incident
having learned how
inhumane, those people
hardly count as human.
OK, five minute break.
Our principles of
individual selection,
kin selection,
reciprocal altruism,
begin to give us insight into
circumstances where evolution
should select for
more aggression,
for more warfare
along those lines.
Now, the flip side--
what is it in the realms
of these basic building
blocks of evolution
that will push for more
cooperation, more empathy, more
affiliation, less violence?
Individual selection
level-- we already
know some of these
examples, which
is that whole world of
alternative male strategies,
that whole world of sometimes
if you're a male baboon,
you could pass on lots
of copies of your genes
by fighting like mad
and being high ranking.
And sometimes it's by
bypassing all of that
and being the nice guy, having
an affiliative relationship,
and female choice
being the thing that
winds up increasing the number
of copies of your genes.
So the possibilities of
alternative mating strategies,
the possibilities of, of
course, parental behavior,
and all we need to do
there is switch over
to the world of South
American pair bonding monkeys.
And those are not animals
with particularly high rates
of aggression.
So all of those
are circumstances
where that could potentially
be perfectly genetically
viable alternatives
to natural selection
selects for higher
degrees of violence
because it passes on more
copies of your genes.
OK, kin selection-- so we've
just gone through kin selection
insofar as it can
generate pseudo kinship
and make you a better,
more murderous soldier
who is more willing
to give up your life
for your band of brothers.
And conversely,
pseudo speciation,
they hardly even
count as humans.
The flip side, of course, ways
in which the human capacity
for pseudo kinship can be
used to decrease violence,
and to make things more
peaceable, and to make people
feel more connected
with each other.
This is a ritual in
all sorts of societies
where you generate
pseudo kinship
as a means of generating peace.
One example, traditional Bedouin
society, here's what happens.
You have two groups who have
been having tensions, who've
been fighting, who have been
having some clan warfare,
whatever.
And they have now
figured out a way
to have a treaty to stop
fighting with each other.
Here is the ritual
that is done, which
is a bunch of the old guys
from each of the groups come.
And they sit down.
And they start exploring
each other's genealogies.
Who is your great grandparents?
Who is your great, great, great,
going through all of that.
And at some point, one
of them has the job
of making up an imaginary
relationship between the two
groups.
Chuck, are you kidding?
I had a great, great
grandfather named Chuck also.
We're relatives.
A ritual absolutely transparent
that people go through
there to generate a supposed
rationale for relatedness,
a big ceremony of
pseudo kinship.
Another one is seen in some
aboriginal groups in Australia.
Apparently, this is a
motif that pops up often
in aboriginal rock art.
And, apparently, it's a symbolic
version of this phenomenon.
OK, you've got
somebody wandering
through the great
back of beyond there.
And there are very
few sources of water.
There's a water hole up ahead.
You've just walked 10
miles to come to it.
And you suddenly
notice a stranger
coming towards the water hole
from the opposite direction.
And this is a water hole that
is essential for you to survive.
You are not going to be able
to walk far enough to get
to the next water hole.
Maybe what you should
do, just in case
this person winds
up being aggressive,
is you should attack him
first-- a virtual guarantee
of aggression.
Here's a ritual that has
been worked out instead
that bypasses it.
The two individuals sit
down around the waterhole.
And each starts giving
their genealogy.
I am the son of, who's the
son of, who's the son of.
Into the next bar
mitzvah, whatever.
Oh, we're relatives.
Let's share some water.
They don't fall for
it for a second.
But it is a totally artificial
mechanism of pseudo kinship
to make it possible
for two strangers
to share this absolutely
essential for life resource,
and not try to kill each other.
Same sort of thing,
pseudo kinship
in all sorts of historical
examples, of revolutions.
Revolutions generating
pseudo kinship,
what is often the term
people use for each other
after the revolution?
Sisters, brothers unite,
pseudo kinship terms.
In French, for example, there
is in the informal to tense.
And there's the more formal one.
And you're supposed to
use the more formal run
sort of in the outside world.
And in the aftermath of
the French Revolution,
it became illegal to address
somebody, a stranger,
in the formal tense.
It always had to be
with the familial
to tense there, pseudo
kinship, more and more of it.
So this brings up
what is initially
a really, really depressing
set of studies, which turn out
to have a very nice optimistic
resolution to them--
very disturbing work.
Work done by a number
of labs over the years
most notably, Elizabeth
Phelps, who is at NYU.
And this is work using
functional brain imaging,
amygdala, all of that.
You put people in
a brain scanner.
Actually you put one in.
And you put them
in one at a time.
And what you do is you're
flashing up pictures to them,
flashing up pictures
of people, of faces,
of faces at a rapid speed.
So there's virtually no
conscious processing.
This is all tapping
into subliminal stuff.
And what she reported, and
what has been replicated
by a number of other
groups since then,
is that you get
activation of the amygdala
on the average in people
when you subliminally
flash up pictures of
somebody of another race.
Whoa, shit, that is
distressing to have been found.
That is not a good
thing, because this
is totally rapid subliminal
stuff, and replicated,
some of the best people
in the field showing this.
My God, the amygdala
has an us/them
that's, in effect,
there in a quarter
second after seeing something.
This is hopeless.
We are so dichotomized.
This is a disaster.
In the years since then,
much more interesting stuff
has emerged.
And this has predominately
been research
by Susan Fiske at Princeton
showing that it doesn't
necessarily work this way.
OK, here's what you do.
First version,
you tell somebody,
I'm going to be
flashing up pictures
of faces while you're lying
there in the brain scanner.
And what you do
is you force them
to look at the picture in
a way where in a purely
mechanical visual viewing,
you're going to say,
some of the pictures
have a big red dot
right in the middle of it.
And any time one
of those comes up,
I want you to press this button.
In other words, just
process the picture
for just a visual pattern.
You do that.
And the amygdala
doesn't activate
when you see a picture of
somebody of another race.
OK, this is not very exciting.
Now, the next thing
she would do--
get people to start
thinking categorically.
Here's what you do.
She would now have people
going in there saying,
I'm going to give you a bunch of
pictures, flashing up pictures.
And what I want you
to do is to stop.
I'm going to stop
at some of them.
And I want you to look closely.
And tell me, do you think
this person is older than age
30 or younger than age 30?
In other words, what you have
just requested the person to do
is think of the
face in the picture
as belonging to a category,
rather than as an individual.
You're going to look
at this picture now.
And you don't really need
to care who the person is,
or what they look
like, or anything.
All you need to do is think
of them as part of a category.
And when you bias
people like that,
and you flash up the picture
of somebody from another race,
the amygdala gets
even more activated.
You have primed somebody to
think not about individuals,
but to make them think
of people in categories.
Finally, what she shows
is exactly the opposite.
Now what she does
is prime something,
a totally neutral
sort of priming,
to try to get people to think
of the person in the picture
as an individual.
And she asks totally
innocuous, neutral things
along the lines of, I want
you to look at the picture.
I know this sounds silly.
But I want you to
look at the picture.
And tell me, do you think is
this the kind of person who
likes Coke or Pepsi?
Totally sort of
diagonal orthogonal
to all of this stuff,
get someone doing that.
And now the amygdala
doesn't activate.
All you need to do in that study
is subliminally prime someone
to think of someone who
they're about to look
at as an individual, rather
than as part of a category,
than as part of a group.
This is not rebuilding society
so that we change our us/thems.
This is a minor prompt 30
seconds before somebody has
the pictures flashed at them.
That's all it took
in these studies.
More good news emerged,
which was that you would also
see separate of these
sorts of manipulations,
long-term developmental
aspects that were predictors
of this phenomenon.
People who grew up in racially
and ethnically diverse
neighborhoods didn't have
this amygdala effect.
People who had had a
significant relationship
with a significant
other of another race
did not have this
amygdala reaction there.
So the easy solution to
this being depressing--
OK, early childhood, exposure
throughout life, that's great.
That's very good news.
But even more remarkable in
her studies is just a prompt.
Prompt somebody to think of
that person as an individual.
And your amygdala is not doing
an us/them with them anymore.
Now, this whole business
about if you grew up
in a diverse neighborhood,
that taps into a whole field
called contact theory.
The notion that
aggression is decreased,
affiliation is increased,
if people have grown up
with lots of contact with
people from other cultures,
other societies other
religions, all of that,
or if people live
in contact with it.
And, in general, what this
large literature shows is
it does work that way.
Contact theory, growing up
in diverse neighborhoods,
growing up in
diverse communities,
increases the likelihood
of a broader umbrella
of what counts as an us.
That's good.
Where does it not work?
One realm where most of
the studies have shown this
is a realm that's
totally heartwarming.
And it would be
great if it did work.
But most of the studies
show that it doesn't.
These are the circumstances
where somebody puts up
the money to take some really
poor Irish Catholic kids
in Belfast, and some really poor
Irish Protestant kids in there
during the worst of
the civil unrest there.
And they get to go to someplace
wonderful and far away.
And they all go to
summer camp together.
And they have teams that
are mixtures of the kids
by different religions.
And they're growing.
They're growing to recognize
each other as individuals.
Or the versions, lots of
which have been tried,
of sort of retreats or even
camps of Palestinian teenagers,
Israeli teenagers.
These are the leaders
in the future.
They will go back and
have learned they're not
so different after all.
They're kind of just like us.
What those studies
have generally shown
is that doesn't work.
It works for only
a little while.
You can't just pull it off
on a two-week camping trip.
It takes more
sustained exposure.
It basically requires growing
up in, or living sustainedly in.
So that's been a disappointment.
One additional disappointment
with the contact theory
literature, which is one of the
papers, which again I think I
put in the suggested reading.
OK, so you've got
two different groups,
two different populations,
two different ethnicities,
whatever.
And they are living in
generally the same area,
but nonetheless segregated
within group in smaller areas.
One scenario-- here's the region
where these two groups live.
And there's an absolute
boundary between them.
Here, instead, there's sort
of an undulating boundary.
It's less clear.
And, critically, there
is more surface area.
There is more interfaces
between the two groups.
There's more domains
of experiencing people
from the other group.
Finally, versions
where instead you
have pockets of different
groups embedded in other ones.
And that being a completely
different scenario
where, in fact, you maximize the
perimeter that you get there.
And what's been shown
in this one study
that I recommended that you
guys look at is the more
contact, the more
interfaces, between the two
groups and living situations
doesn't guarantee that people
will get along better.
What you will find is there's
intermediate points where
the contact profile
increases aggression,
because what it does
is you just barely
have a critical mass
of people on your side
to be an effective group
to fight with them.
You see totally
different outcomes,
depending on the
spatial characteristics
of the subgrouping.
And what the people
showed in this paper was
they then analyzed the
different ethnic distributions
in the Balkans, the Bosnian
War, the Croatians, all of that,
and seeing that this was
extremely predictive of where
the violence took place in
terms of where you had what they
viewed as the least optimal
set of interfaces of contact
between groups.
More contact is not
necessarily always equal,
more understanding and
we're all just the same.
More contact can equal, in
some cases, more irritation,
and more resources, and more
unity to do something about it.
OK, more of pseudo kinship--
so this whole notion, again,
of pseudo kinship,
we are species
where we're not
recognizing individuals
by smell, all of that.
We're doing that
cognition stuff.
But don't forget the
[? kibbutz ?] study.
But we're doing that
cognition stuff.
And, thus, we can
do pseudo kinship.
And, thus, we could
be manipulated
by powers that be, by
governments, by religions,
and to viewing non-relatives
as more related to us,
and all of that.
These are very
abstract processes.
And it brings up another realm,
an extremely abstract realm,
that pushes for more
cooperation and less violence.
And this goes back
to what I was talking
about the other day, the
neurobiology of symbols,
how we code for certain
types of symbols,
certain metaphors in our brain.
And that's back to
that whole world
of, you're using the
same part of the brain
for disgusting food and
moral disgust, warm drink,
warm personality, that
weird concrete literalness.
Because you've got a
pretty metaphors somewhere
when humans started
developing them,
the outcome of that
being that metaphors
can be extraordinarily powerful.
And a number of
researchers-- probably
the person most visible in
this realm, an economist
University of Michigan
named Robert Axelrod
as doing a whole lot of
work showing, in a sense,
the importance of
symbols in peacemaking.
And it makes perfect sense.
You take the extreme
rationalist view
of humans as economic machines.
And what peacemaking is
going to be purely about
is figuring out
contested resources
and how they are going
to be divided up.
And what Axelrod
and others show,
instead, is this whole
irrational realm of,
be respectful of
somebody else's symbols.
And figuring out how you're
going to divide up the land
suddenly becomes a
lot less important--
the power of symbols over
rational contested resources.
And he studied things like
how a critical thing that
happened in peace coming
to Northern Ireland
was at one juncture a bunch
of the Sinn Fein, however
that's pronounced, the
ex-military wing of the IRA
that were just beginning
to have extremely
mistrustful negotiations with
some of the Protestant unions
and all of that.
They did something outrageous.
They sent a 50th
wedding anniversary gift
to this guy Ian Paisley,
who was the murderous head
of the Protestant
death squads there.
Somebody just
decided to try this.
And this was a
massive breakthrough.
Anyone who saw that movie
Invictus or have read about,
the utter brilliance
of Nelson Mandela,
of having spent his
time in prison learning
to be completely
fluent in Afrikaans
so that when he was sitting
down and starting to negotiate
with these people, the fact that
he could sit there and speak
in their language,
a language that
is so laden with
symbolic importance
to Afrikaners, that that
was a gigantic symbolic coup
of Mandela embracing
the sport that
was the very symbol of
apartheid, of Mandela doing
very subtle things
that a number of people
pointed out who were
involved in the negotiations.
OK, Mandela, just when
he's gotten out of prison,
and he's about to meet
with some of the leaders
of the government, and some of
the most right wing opponents
to any sort of peace.
And so we need a
conference room.
And, no, that's not what he did.
He insisted they would have the
meetings in his home, his home
that he had just returned to.
OK, well let's clear off
the dining room table.
No, that's not what he did.
He would insist they did this
in the living room, where
they would sit down on
stuffed armchairs and couches.
And something that he did,
apparently, always at these
is he would sit down on the
couch, and gesture to whoever
was likely to be the
most impossible foe,
and say, come sit next to me.
Sit next to me on the couch.
And would proceed to jump
up at various points to say,
can I get you some more tea?
Do you want some more--
there would be food.
There would be biscuits.
There would be whatever--
brilliant, brilliant use
of symbols.
If I'm sitting
here, and this guy
keeps jumping up and getting
me more cookies just when I
was getting a hankering
for some more cookies,
maybe not so
different after all.
People who get cookies
for other people
make the world more peaceful,
or something or other.
What Axelrod has also
shown in some of his work
is the potential for it--
really interesting stuff.
He will, for example, he
and people working with him,
have interviewed, say, Hamas
leaders in Palestinian,
and the Gaza, and the West
Bank, some of the most
opposed to the existence of
Israel, most confrontational
of groups.
And he gets quotes from their
leaders along the lines of,
if the Israelis would
ever once just say,
we got screwed in 1948.
And we're sorry it happened.
We would be willing
to make peace.
And then he goes and talks
to some Israeli generals
who are some of the
most right wing ones.
He selects them for that.
And they sit there.
And they say stuff like, if the
damn Palestinians would ever
just get the anti-Semitic
garbage out of their school
books, we'd be able to
think seriously about peace
the next day.
It's not about water rights.
It's not about return of land.
It's just about, are
they going to respect
our symbols and the
legitimacy of our history,
and the accuracy of it?
Enormously, potentially
powerful interventions there.
OK, so kin selection-- most
importantly, pseudo kinship.
Moving on now--
reciprocal altruism.
Where does that come in, in
terms of potentially making
for more peace?
And what's clear
is, in principle,
it should never do it if you
are playing only a single round
of a game with someone, a
game in the prisoner's dilemma
sense, because there's
absolutely no reason
to cooperate,
because you are never
going to face the person again.
And this is something that was
called by a zoologist Garret
Hardin the tragedy
of the commons,
and the circumstance
of shared resources
but limited responsibility, and
limited repeated interactions.
You have to select
for selfishness.
You have to select for what
is termed a Nash equilibrium,
where the only possible
rational thing to do
there is to not cooperate.
So how do you ever
get cooperation
to evolve in groups
of organisms?
So back to the same Axelrod,
his work with computer
tournaments there,
with a tit for tat,
seeing that under some
circumstances one of them
can dominate.
Tit for tat is a
great optimal one.
In the real world,
though, how do you ever
jump start cooperation?
How do you ever get one
of those strategies going
when the starting state is
complete lack of cooperation?
We already know one example,
which is founder populations,
that whole business about get
an isolated population has
a higher coefficient
of relatedness, inbred,
out of kin selection.
Establish high degrees
of cooperation.
They come back.
And it's this group
selection phenomenon of,
you better become as
cooperative as them.
Or you're not going
to be able to compete.
And you could see
the same exact thing
in circumstances where
it is not a founder
effect of a population
goes away for a while
and then comes back, but where
a population is functioning
in that way amid a sea
of non-cooperators.
In New York City
in the 1980s, there
was this totally
weird phenomenon
in that there were
two ethnic groups that
were moving into New York
at a much higher rate
than in the past--
Korean immigrants
and Lebanese immigrants.
And both groups happened to
gravitate towards grocery
stores-- the Korean community
fruit, vegetable stands,
the Lebanese community more
regular old grocery stores.
And they were
incredibly successful.
And these popped up
all over the place.
And the people who already
had the fruit and vegetable
stands and stuff started
complaining that they
were at an unfair disadvantage.
How come?
Because these Korean
shop owners would
cooperate with each other.
They would give each
other interest-free loans.
That's not fair.
That's not fair that they're
being nice to each other.
We can't compete.
And the same thing with the
Lebanese grocery owners,
that you had people
doing reciprocal altruism
in a community of trust.
And what they were
immediately doing
was out competing
the non-cooperators.
And amid these bizarre demands
for, like, banning Korean fruit
and vegetable stands,
or some-- like,
this was a point
of great hostility
during that period
in New York City
because those people
were cheating.
They cooperated with each other.
So either join in.
Or you will be
driven to extinction.
So that is one possibility.
What are the other circumstances
in formal game theory
play that favors the
emergence of cooperation?
Critical one--
repetition, that you're
going to play against this
individual more than just once.
If it's run time, it's
tragedy of the commons.
There is absolutely no reason
to select for cooperation.
Repeated interactions,
and it opens up
the possibility of
you being punished
for being a cheater,
what they call
the shadow of
future retribution.
One qualifier with
that, though-- you
need to have multiple
rounds of interactions.
But it can't be a
known number of rounds.
You can't know how many
rounds it's going to be.
Think through this.
You know that this is
the very last round
you are going to play.
And what's the only logical
thing to do is to cheat?
The very last round
functions as if it
was a tragedy of the commons
single game, single round game.
So the only logical
thing to do is
to cheat in the very last round.
In which case, the only
logical thing to do
is to cheat in the
next to the last round,
and the next to the last.
A known number of
rounds of interactions
immediately does in
cooperation because it sort of
flows backwards with this
collapse of the system.
The next thing that favors it
is what is called open book
play by people in the
business, which is you
will be playing against a
number of different individuals,
and pairs, cycling through.
And the critical
thing is when you
begin to play with
someone else, they
can know your record as to how
you played in previous games.
In other words, once
you bring in reputation,
when reputation can be
possible, suddenly you
select for cooperation.
Next, what's shown is that
if you have people playing
in multiple games
with each other,
especially when
they're unsynchronized,
you select for
cooperation as well.
What's this about?
What you do is if one of
the games makes it very,
very easy in terms of
payoff for cooperation
to get established,
if you intermix rounds
of that game with a game in
which there is very little
motivation for cooperation
starting, what you see
is a psychological bleed over.
If you are cooperating with
this person in this game, which
is now done here now
down here, it greatly
increases the odds of one doing
the other game of beginning
to cooperate as well.
Multiple games, and
it does not take
much to see that this is
more like the real world
than playing prisoner's dilemma
with one single individual.
Next, the possibility
of punishing someone
when they are a creep.
And that's what we
heard about before, what
is termed now in the field
altruistic punishment.
If somebody does
something crummy to you,
you are allowed to
expend a certain amount
of your resources to take
more of the resources
away from them.
That selects for cooperation.
Something that
even selects faster
is second party
altruistic punishing.
You are not taking
part in the game.
You're watching these
two individuals,
But you have the power to
use some of your resources
to punish a cheater--
an outside enforcer.
That selects for
cooperation even faster.
Then something that is even
more effective, which is
termed secondary
altruistic punishing.
Here's what you do.
What you do is
people are observers
of other people's interactions,
and seeing if they're cheating.
And they can do some
altruistic punishment
if they think this individual
is a jerk and all of that.
But here's what you do.
If there is a circumstance
where somebody cheats
and this third party
individual doesn't punish them,
they get punished.
What's that about?
That's honor code violations.
That's the expectation
that you are
supposed to report someone
who has had an honor code
violation.
And if you don't, you
will get punished.
That selects for cooperation
really fast also.
And all of these-- these have
been computer tournaments,
and all of that.
You know that world
of research by now.
Finally, more subtle
stuff, gives the person
the opportunity to
drop out of the game,
to secede from the game.
Give the person the opportunity
to not play against you,
but to choose, I'll play against
all these other individuals,
but not that one.
Begin to put that
power in there.
And you select for
cooperation that much faster.
So that's some good news.
Final level, the group selection
level-- group selection
not in our behaving for
the good of the species,
but as we know the more
modern version of it,
selection for
traits that are only
manifest at the level
of whole groups.
A always loses to B. But groups
of A always defeat groups of B.
All of the stuff
we've been seeing,
people suddenly cooperating with
each other as a small group,
and driving the non-cooperators
out of business,
that's a group selection
argument going on there.
So you can have that as
a means for generating
a lot of cooperation.
That's great.
That makes the world
a better place,
unless there is
a downside to it.
And back to
chimpanzees, what do you
have when a bunch
of related chimps
are having not individual fights
with males from the next valley
over, but functioning
as a group?
You are having an example
of group selection, which
thus brings up one of the
most profoundly scary things
on this planet,
which is when you've
got a bunch of males
who are getting
along well with each other.
And they're beginning to
look at the neighbors,
because lots of males
cooperating together
can make for some
very bad neighbors.
As some people in the
field have emphasized,
a decrease in homicide
within a group
is a prerequisite for inventing
genocide between groups.
So group selection is not always
this magical founder effect
of everybody wanting to
learn the new folk songs.
What you've got instead
are circumstances
where it can go very wrong.
Final amazing example
showing the emergence
of cooperation--
and this was not
a game theory demonstration.
This was not an experiment.
This was a real
event that happened,
and an extraordinary one.
This occurred during World
War I. A lot of people
have heard about a phenomenon
that happened there,
a historical incident
that was very, very cruel,
but pales in comparison to
what I'm about to tell about.
In 1914, the first Christmas
of World War I, somehow
the decision was made
that there was going
to be a truce on Christmas Day.
All of the fighting up
and down the trenches
was going to cease for 24 hours.
And it has been documented.
It was amazing and bizarre.
Men out of the
trenches playing soccer
with each other from different
sides-- a bunch of German
and French guys playing against
some British and German guys
on the other side,
people exchanging gifts,
people exchanging
helmets as souvenirs,
people singing together,
people getting drunk together
from the two opposite sides.
And, eventually,
when the officers
got them to go
back to their job,
they returned to trying to kill
each other-- amazing, bizarre
incident.
What was very striking
about it is it extended,
actually, two or three
days extra longer than
planned because the
officers couldn't
get people to stop doing this.
That's very cool.
But that's an outside
force already establishing
the cooperation.
Here's something much,
much more impressive.
And this happened
in World War I.
And it didn't take a bunch of
generals or heads of states
to negotiate a truce--
the way in which truces
would spontaneously
merge over and over again
across the trenches.
How do you generate a
reciprocally altruistic
cooperative relationship
with the enemy
in the trenches
over there, where
you don't speak
the same language
and you don't even
see their faces?
Here's what you do.
You take your best gunner.
And have him come
up and lob a shell
20 yards behind the trench
there, and blow up a tree.
Now have you gunner lob a shell
to hit the exact same spot
again, and do it
again, and do it again.
Do it a bunch of times.
What are you communicating
to the other side?
This guy's really good.
And we're choosing not to put
the missile down on top of you.
What are you going
to do about it?
And then the other side would
get out their best gunner
and do the thing in return.
And you have just worked
out a non-aggression pact.
And this occurred
over and over again
in the trench warfare,
documented in letters
by soldiers back home
to parents, saying,
hi Mom and Dad.
Things are OK here.
I hope you're worrying
less, because we've
worked out something.
Things are a lot better here.
There's a lot less
people getting hurt.
Working it out along those
lines, working out a tit
for tat vulnerability
where you had
to have a forgiving tit
for tat, what if somebody
messed up and
accidentally dropped
a shell into the trench
on the other side?
They got one shot back.
Letters, dear Mom and
Dad, things are OK here.
We had an incident
the other day.
We had this new gunner
who didn't really
understand how things worked.
And I heard he killed
four people on their side.
They shot one back.
They took out three
of our people.
But everything is OK now.
Tit for tat, complete
with a forgiving element--
this happened again,
and again, and again,
in the trench warfare.
And the only thing that
stopped it from spreading
is the fact that
the officers kept
insisting that nobody
else was doing this.
And these guys were going to
get shot and court marshaled
if they didn't stop this.
And if they had only
had cell phones,
if they only had
communication, if they only
had a way of knowing
up and down the line
that everybody was
doing this, they
would have stopped the
war-- not with a treaty,
not with generals, not
with heads of state,
not with diplomats,
but simply a bottom
up way of evolving cooperation.
And they would have
stopped the war
if they knew that they
weren't the only ones wanting
to do this-- amazing
historical incident.
OK, so this gets us to
the end of aggression.
As you probably noticed,
this has gone on way long.
This is the longest
amount of material
we spend on anything
in the course.
And each year, it
actually gets longer.
And I actually think I
know the reason for it.
Three and a half
lectures ago, where
did I start off talking
about my recent exposure
to human aggression,
which was my doing it,
and tripping up that
jerk playing soccer.
And everybody was all excited.
Let me tell you
about another time,
the most serious
time I have ever been
exposed to human aggression.
This took place
when I was about 20.
And this was first
year that I was
doing research in East Africa.
During that time, the famed
notorious dictator Idi Amin
was running Uganda.
And he was a nightmare.
He was just killing
people left and right,
destroying the country, as
documented, cannibalizing.
Was a nightmare of a dictator.
Around the time,
he made a mistake.
This was spring of 1979, which
is he invaded Tanzania and took
over some of the
land there, thinking
the Tanzanians
wouldn't fight back.
And he miscalculated.
The Tanzania army
counterattacked, and drove them
out of Uganda, and decided to
drive all the way to Kampala,
the capital of Uganda.
And they overthrew Idi Amin.
He fled the country.
And the country was liberated.
They continued through there.
And they opened up a corridor
to the Kenyan border.
So it was now a swath all
through the southern part
of the country that was
controlled by Tanzania.
So the day after the
Tanzanians got things
to the Kenyan border,
I went into Uganda.
OK, why?
This was amazing.
This was history happening.
You were hearing on the BBC
that people were dancing
in the streets in Kampala.
They had been liberated,
amazing chance to see history.
This was-- through
our college, I
had been spending a lot
of time with Quakers,
and wrestling with those
issues, and figured
if there is anything that
counts as a just war,
this would be it.
What does this seem like?
All these philosophical
principles.
This, actually, of course,
was not what was going on.
I was a 20-year-old male.
And somebody had been staying
with me, and no longer was.
And I was all bummed out.
And, thus, I did sort of
a very 20-year-old male
adolescent primate thing,
which is figuring some violence
would do some good things
for my brain neurochemistry.
And I wanted to go see a war.
So I went off to Uganda,
hitching through there.
And it was
appropriately exciting.
And some things happened that
scared the bejesus out of me.
And at some point, I finally
decided I have had enough.
I want to go back to Kenya.
I want to feel safe again.
So I'm hitching back.
But I had one last
thing that I want
to do, which was
since I was a kid,
I had grown up reading
about the explorers,
and the search for the source
of the Nile and all of that.
The source of the white
Nile is in Uganda.
It comes out of Lake Victoria
in a town called Tororo.
And there's a spot
there, a bridge
where you can go and stand.
And here is where the
Nile River begins.
And I had to see
this before leaving.
And I managed to get
a ride into there.
And I managed to get over to
this bridge, and stood there.
And there was this
sort of dam thing
that was built that
this bridge was on top.
And there was this sluice where
all the water came spritzing
out, and started the Nile.
And I stood there.
And I looked over the side.
And what I saw was there
was a Ugandan soldier
who had been taken down there.
There was a staircase along the
side down to some sort of panel
for controls or whatever.
And a Ugandan soldier
had been taken down
the steps, his hands
tied behind his back,
and a rope tied
around his throat
and attached to the panel.
So that as the
water level rose, he
would eventually be
swept off his feet
and would be strangled
and drowned in the water.
And this body had obviously
been there for days.
It was bloated.
It was floating there.
It was being bashed
around on the waves.
There were crocs
trying to get at it.
And looking at this guy, a total
storm of emotions-- thinking,
good, that's what you deserve
being in the army for Amin.
Then thinking,
no, wait a second.
This is probably some poor
guy who was forced to do it
and was just following orders.
Then thinking, no, I know
what I think of soldiers
who just follow orders.
Then thinking, whoa, I would
love to get a lot closer
and see what's
happening down there.
And thinking, I want to get as
far away from here as possible.
And I stood there for
an hour and a half
at that spot staring at this guy
until some Tanzanian soldiers
chased me away from there.
And I think now, 33
years later, that I
lecture longer and longer about
aggression each year because
of that guy.
What do we do here
in our business?
We have this general notion
that if we are rational,
if we are learned,
if we are scholarly,
if we respect thoughts
and truth and all of that,
we will make the
world a better place.
All of us who are professorial
have somewhere in there
this totally ridiculous
belief that if you're
allowed to lecture at
a subject long enough,
it will give up and go away.
And that will be the cure
for world aggression.
If everybody can
only be lectured
to about the frontal cortex,
it will solve world violence.
But the basic problem
is that aggression is
such a messy set of behaviors.
Schizophrenia-- no question
about it, bad news.
Alzheimer's disease, childhood
cancer, global warming,
all of these
unassailably bad news.
But aggression is a whole
lot more complicated,
because of that point
where we started with,
which is the same
exact behaviors,
and depending on the
context, it could
be something that would get
a medal for someone, someone
you will want to mate with, vote
for, reward, cheer on, join in.
And in another setting,
it is the most frightening
possible thing that
can happen to us.
And it's the same behaviors
in all those cases.
And it's for that reason,
that violence is always
going to be the hardest
subject for us to understand
biologically.
And it's for that
reason, that it's always
going to be the one we have
to try hardest to understand.
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