What Makes Us Clever? A Horizon Guide to Intelligence (2011) - full transcript
What is intelligence?
8175 backwards?
5718.
What does an entomologist study?
Wow! That was tough. Did a lot of
people get this one in two minutes?
And why do some people apparently
have so much more of it than others?
Where does intelligence come from?
Is it a matter of luck, biology
or just a good education that
makes this guy cleverer than me?
Is there anything that I
or my parents could have done
to make me more intelligent?
Well, scientists have been battling
thorny questions like these for
decades, making intelligence one of
the most studied traits in science.
But it's only really now that we
are beginning to get some answers.
For nearly 50 years,
Horizon has been following
that search to understand
our mysterious mental power,
looking at everything from
our evolutionary history to whether
a computer could outsmart us.
And asking the questions,
how do you test for intelligence?
Is it inherited or innate?
Nature or nurture?
In so doing, science has begun
to redefine our understanding of
what makes every one of us unique.
The benchmark for measuring one
person's intelligence against
another is the iconic IQ or
Intelligence Quotient test.
Most of us will have sat through
one of these at one time or another.
It is the dreaded IQ test, with
sections on spatial awareness,
general knowledge and reasoning.
And it tots up different areas
of skill to create one score.
A single mark that can brand you
with either a low, high
or maybe an average IQ.
Now, we've been judged on the
merits of this test for years now.
What's remarkable about it
is that it was introduced in 1912.
So, essentially, this has remained
the same for almost 100 years.
In 2006, Horizon tested the IQs
of seven experts in their field
to see who would come out on top.
Seven people from seven
very different backgrounds.
All highly successful.
And all seven prepared to do battle
over the elusive nature
of intelligence.
The test lasts 30 minutes.
What it revealed would show how our
understanding of intelligence
has changed since the IQ test
was first devised.
We have spent 100 years on
IQ tests that are basically the same.
Imagine if physics or chemistry or
medicine or biology were the same
today as they were 100 years ago.
That's essentially the state
of the testing industry.
It's unusual to find a methodology
that has changed so little.
And perhaps this reflects the
century-long struggle to work out
how intelligence develops.
In their bid to understand human
intelligence, scientists have looked
for evidence of it in other animals.
During the 1980s,
Dr James Gould searched for
signs of intelligent behaviour
in the complex lives of bees.
Even now, when I look at bees,
it's hard to imagine that these tiny,
nervous little insects
could be intelligent.
Yet, in all this apparent
chaos, there is a
tremendous amount of order.
Bees are not behaving randomly, they
are going about the task of solving
a series of specific problems.
They spend the first few days feeding
the queen and taking care of her.
And then they spend a few days
building honeycomb in the hive.
And then a few days
guarding the hive's entrance and
then, finally, several weeks
gathering food from flowers.
These are all clever things and yet
this behaviour is driven
by biological cues.
All through the life of a bee,
an innate sensitivity to certain cues
helps guide its behaviour.
And this is by no means an exception,
this is the rule in the animal world.
And it makes sense, too.
If the behaviour is sufficiently
predictable and the cues are
sufficiently predictable,
it makes sense for an animal not
to reason out what it ought to do,
but to simply respond automatically.
A good example of this is
tits open milk bottles
because instinctively they peel
back bark to look for grubs.
Gould concluded that, unlike humans,
the short lifespans of many insects
and animals means they simply don't
have enough time to work
out solutions to problems.
Their apparently intelligent
behaviour is just a response to
a series of biological cues.
However, there are animals that
do appear to display a capacity
for intelligent problem-solving.
Research into one species -
chimpanzees - has begun to
reveal greater capabilities
that go beyond pure instinct.
Writer, Danny Wallace,
went to Uganda to find out more.
He was keen to investigate
an experiment to test a chimp's
ability to solve a complex problem.
This box of bananas placed away
from the cage poses a tricky problem.
Ah.
I see what you've done.
'To get the bananas to come
towards me, I would have to pull
both ends of the rope.
'But they were too far apart.'
Right, OK. I can't.
Diana?
Will you be another chimp, please?
Chimp-cam.
'I could see that if
I didn't get Diana involved,
I'd get no bananas at all.
'And that didn't bear
thinking about.'
One, two, three.
We did it, we got the bananas.
Now for the chimps.
Chimp one has a rational choice.
Share the bananas with chimp two
or get no banana at all.
Three, two, one. Release the chimp.
OK. So, he's going a bit mad.
Chimp one can't get the bananas.
Chimp two is going mad, chimp
one is wondering what's going on.
Oh, he has let him out.
That's amazing.
That's incredible.
Chimp one, he's very happy,
and off they go.
That was brilliant.
That was quicker than me.
The chimp appeared to be
making a thoughtful decision,
suggesting that chimps are
intelligent enough to co-operate.
A key human trait.
Yet human intelligence
still sets us apart from our
closest evolutionary cousins.
Thank you for taking part
in this experiment. This is for you.
Scientists have delved
deep into our prehistoric
past to try to find out when we
developed superior intelligence.
When did our ancestors
cease being brute animals
and first become truly human?
When did we learn to think?
Thinking is the defining
trait of humankind.
It has given us machines.
Technology. Power.
No other animal has the ability
to look at the world outside
and transform it.
Where all other animals live from
day to day, we alone plan ahead.
Dream. And create.
Find the day we learned to think
and you would have identified perhaps
the single most important moment
in human history.
But it was not going to be simple.
Thinking leaves no traces.
There are no fossilised
thoughts waiting to be dug out
of the ground and dated.
It was like investigating
a murder scene without a body.
So, scientists had to
look for indirect clues.
Not fossils, but other
evidence for when thought began.
And then they realised that thought
must have come hand-in-hand
with something else.
What are we going to look for,
first of all, that's going to
give us evidence that humans
were behaving in a modern way?
So we look, in a way, for proxies.
But there was one kind of evidence
archaeologists could look for.
The obvious line of evidence is art.
When you get unquestionable art
that's widespread and common,
I think you can say you're
dealing with people just like us.
Only humans create and
can make sense of art.
I'm sure that dozens of dogs
have walked down this street
in the past years
and perhaps not a one has glanced up
in awe or wonder
and thought
to himself, what does this mean?
For a dog, this is colour on a wall.
Perhaps even less than that.
But to a human being,
a painting is far more than
just a collection of colours.
An expression of thought.
Suddenly, what they had
to look for was clear.
Discover the earliest
forms of human art
and you would have found
the day we learned to think.
At Blombos, on the east
coast of South Africa,
anthropologist Chris Henshilwood
had been quietly excavating his
prehistoric cave for over a decade.
This is Blombos cave here.
A very special find.
We're really
looking at what has been left here
almost as if it was
put down here yesterday.
As they dug down through the floor of
the cave, his team were going back to
an ancient time of human habitation
tens of thousands of years ago.
We came down onto this layer
you can see over here,
which really was quite remarkable.
On the surface were lying
the most beautifully made artefacts.
Bone points, spear points as well.
And immediately I realised we had
gone back a very long way in time.
The beautifully crafted objects
were dated to over 70,000 years ago.
But there was still not proof
the people in the cave
were thinking people,
like us.
One type of item started appearing
over and over again.
We noticed large numbers
of pieces of ochre.
8,000 pieces of ochre
in the old levels alone.
Then, one day, Henshilwood
found a piece of ochre
that was different from the rest.
We found this piece of ochre,
brushed up the side and there was
this absolutely remarkable
pattern revealed.
There was huge excitement,
you can imagine.
The ochre piece appeared to have
been marked with a clear image.
What seemed like an abstract
geometric pattern.
This was a deliberate construction
of a series of crosshatches
in each direction.
A line across the top,
a line through the middle
and a line down the bottom.
So it actually
circumscribed that engraving.
As if they had made the crosses
and deliberately surrounded it
with these other lines as well.
Here is the first example of the
ability of humans to store something
outside of the human brain.
You're storing a message
that somebody else who is part of
that same group can pick up and they
will understand what that meant.
This is the beginning of
things like art, writing
and everything else that follows.
It was the earliest
evidence of the thinking brain.
There is still much that we
don't know about the evolution
of human intelligence.
But it was during the second half of
the 19th century that the ideas of
Charles Darwin began to profoundly
influence our thinking.
Francis Galton was
the first scientist
to propose that intelligence was a
biologically-based mental faculty.
He was Darwin's cousin and was much
inspired by reading his book,
On The Origin Of Species.
Galton thought that human mental
abilities were inherited in just
the same way as the plant and
animal traits outlined by Darwin.
And he set out to prove it.
Galton was obsessed
with measuring things.
He was convinced that
everything was inherited,
from arm length to reaction time.
According to his theory, people with
bigger heads, such as himself,
would have a greater capacity
for intelligence than others.
So he started to measure the heads
of a group of Cambridge students
and compared those
measurements to the test results.
But, disappointingly for him,
the correlation between those
two sets of data was low.
The evidence simply didn't stack up.
But Galton stuck doggedly
to his conviction
that intelligence was inherited.
He coined the phrase,
"nature versus nurture",
which has proved to be one of the
most enduring questions at the
heart of the intelligence debate.
But it was Galton's disciple,
a psychologist named Cyril Burt,
whose research was to have a huge
impact on both our thinking about
and our testing of intelligence.
Horizon dramatised Burt's
youthful idealisation of Galton,
which would have
an enduring influence on his work.
Galton was one of Burt's
heroes, maybe the only one.
Of all the psychologists
whose names were mentioned
in my discussions with Burt, I
think the only one that he seemed to
talk about admiringly was Galton.
This is young Loddy, Sir Francis.
Loddy?
Loderick, sir. It's a shortening.
My first name is Cyril,
then Loderick.
Are you good at your
schoolwork, Loddy?
Oh, yes, sir. Very good.
He's a very diligent boy.
He has a diligent father.
He will have inherited
his father's intelligence.
Burt seemed to worship
Francis Galton.
He kept on mentioning the one
occasion on which he met him.
And he certainly tried to
follow in his footsteps.
Oh, no. Do you read classics?
I want to be a scientist.
Burt was particularly drawn
to one of Galton's ideas.
In 1883, Galton had coined the
term eugenics, meaning good birth.
He believed that people of high rank
had greater intelligence and should
be encouraged to marry and have
children to preserve these traits,
while the poor be strongly
discouraged from breeding.
Burt adopted this idea
with enthusiasm.
For example,
Burt has written out on his hand:
"The problem of the very poor.
"They must be segregated, prevented
from reproducing their own kind".
This is the kind of atmosphere,
obviously, to which he was exposed.
Working in the 1930s,
Burt was determined to prove
intelligence was inherited.
He brought together more evidence
for the inheritance of intelligence
than any other person
had done at that time.
His papers were more impressive
in terms of the number of different
kinds of kinships on which
heritables had been estimated.
The fine grain detail in which the
analyses were carried out. And so on.
Burt introduced the IQ test
as a way of measuring
schoolchildren's intelligence.
He was also to influence the
introduction of the 11 Plus test,
which was to become a key decider
of a child's academic future.
By 1945, every child's
intelligence was tested.
In order to study the inherited
element of intelligence,
Burt looked for subjects that were
the same in every way, except the
environment they were brought up in.
Identical twins who had
been separated at birth.
So now, if you can find, when they
are old enough to be IQ tested,
a fair number of pairs of such twins,
you can give them all IQ tests, and
if their measured IQs resemble one
another, that must be due to the only
thing they have in common, namely
their identical genetic make-up.
It cannot be due to their
environment, in theory, because
they don't have that in common.
Burt announced his findings with a
great flourish, stating that he had
found genetics were responsible
for 80% of his subjects' IQ.
In the crucial matter of
separated monozygotic twins,
and the measurement of the genetic
heritability of intelligence,
over the years we have been fortunate
enough to steadily increase our
sample size to the point where our
data, based on 52 pairs of twins,
is some 30% greater than
that of its closest rival.
Burt's research was highly respected
and in 1946 he became the first
British psychologist to be knighted
for his contributions
to psychological testing.
But his ideas on eugenics
had rather lost their appeal.
Adolf Hitler adopted this philosophy
to murder thousands of people he
labelled mentally defective.
The scientific community
began to distance itself
from the idea of engineering
society according to intelligence.
Burt continued to defend his ideas,
but it was only after his death
in 1971
that scientists, including Professor
Leon Kamin, scrutinised his results
and came to some uneasy conclusions.
As the sample size increased
progressively, in successive papers,
one noted an absolutely
incredible thing.
The correlations, the statistical
results that he reported, remained
identical to the third decimal.
Well, theoretically, that
sort of thing could happen.
Also theoretically, the sun might not
rise tomorrow morning, and that's
probably a more probable event than
what one would have
had to have believed
if one took Burt's number seriously.
All of them remain identical
to the third decimal place.
Clearly something
was drastically wrong.
There's universal agreement
among psychologists that Burt
couldn't possibly have
tested 53 pairs of twins.
That at least the last 32 pairs
must be figments of his imagination.
I take perhaps an even
more sceptical view of Burt.
I think it's reasonable to suppose
that he may never have laid eyes on
a separated twin
in his entire lifetime.
But Kamin was convinced that Burt
was motivated only by his genuine
belief in inherited intelligence.
I don't think Burt thought of himself
as a manipulator and misleader
of the public.
I think Burt had the
intellectual audacity to think
that he knew the truth prior to any
actual investigation of the facts,
and therefore on account of noblesse
oblige, he was letting the rest of
us get a handle on the truth
by presenting us numbers that
would help us to accept it.
And he did us the courtesy of
inventing the numbers for us.
Comprehensive proof of the part
genetics play in intelligence
still remained elusive,
but as the '70s got underway,
that didn't deter one man from
adopting a radical new approach.
In a rather sinister echo of
Burt and Galton's theories,
Californian doctor Robert Graham
reasoned that if there were
intelligence genes to be had, he
could find a way of passing them on.
In 2006, after Graham's death,
Horizon looked back at
his extraordinary quest.
My name is Robert Klark Graham
and I had a dream.
To single-handedly saved the
human race, one child at a time.
Robert Graham believed that the gene
pool was going downhill and that
we needed to do something about that.
He had this grandiose plan
to remake all of humanity.
It had the air of James Bond movie
meets Disney, or something.
Using the sperm of clever men,
I hope to create intelligent kids.
He was this strange scientist
that was trying to breed
the super race.
What we're doing is exploring
the possibilities of genetics.
I was accused of being a racist
and a Nazi.
I can't say that I know much
about Hitler or his vision.
Yet my sperm bank was
operational for nearly 20 years.
Despite tremendous controversy,
I was responsible for the
creation of over 200 children.
I would not be here without Robert
Graham, without his existence, and
in a way, I owe him my life.
Well, I'm Tom Grunwal, and live here
in Temecula in southern California.
I'm Andrea Grunwal
and I live with Tom.
I had had two children
with my first wife,
then with my second wife, I
took the steps to have a vasectomy.
The next thing you know,
I'm divorced.
I never really thought I
would ever have another child
in the rest of my life.
Until I met Andrea.
I finally just spilled my gut
and said, Tom, I don't know
how to say this, but I would really
like to have a baby and I don't
know how you feel about that.
And I said,
OK, if you can figure out how,
let's go for it.
I wanted to offer these women
the seed of clever men,
and for me, scientists
were the pinnacle of intelligence.
With proven, measurable,
practical ability.
I figured, let's start at the top.
We were trying to have
outstanding genes and Nobel Prize
winners possessed them.
Due to your outstanding
achievements, you
would be an excellent donor for our
Repository for Germinal Choice.
We hope to create some very bright
children, possibly a genius or two.
I managed to convince three Nobel
laureate scientists to each provide
an anonymous sample for my bank.
I actually was a little surprised
that some of these older fellows were
able to produce specimens so quickly.
Bob was very pleased when we
took that first look at the
specimen under the microscope and saw
thousands of sperm
swimming vigorously.
He beamed with joy.
Good job!
It's peculiar, but
I didn't think it was weird.
My name is Dr Afton Blake
and I live in Los Angeles,
California, in a little place
called Mount Washington.
Om....
When I first called the repository,
they were very friendly.
They came up the next day
to meet me and interview me.
And I think the very next month
I tried my first insemination.
Choose me as your mother.
Then, 10 months after I had
tried the first time, I conceived.
In August 1982,
having been impregnated with donor
codenamed Red 28, Dr Afton Blake
gave birth to a boy she named Doran.
It was ecstasy from
the moment he came out, looked in my
eyes, and stopped crying,
immediately that we made contact
and the bond was like so incredible.
Everybody liked the name Doran, which
means in Greek, a gift from the gods.
I could never imagine life
without him. It was like suddenly,
what did I have before I had Doran?
I didn't know,
because this was everything.
Do you want to hand me the dog?
I am immensely pleased with
the outcome of the mating
between Dr Blake and Number 28.
We've had a splendid result.
I think no question about it.
Doran is about as ideal, as nearly
as we can judge at his early age,
about as ideal as we could hope.
Everyone wanted to know about
my genius sperm bank child.
Doran represented what
Dr Graham was trying to achieve.
Smart, beautiful.
Everybody wanted a Doran.
They just wanted to come to
our bank and get a Doran.
The phone rang off the hook.
We had arrived.
After 20 years in operation,
my genius sperm bank was
ultimately responsible for
the production of 217 children.
We've got lots of baby pictures.
Jessie ended up being the 15th
baby born to the repository.
People used to just be amazed
at his abilities.
I look at myself as being an
intelligent person and I think that
I'm achieving in the world
all that I can achieve.
And that's something that
I don't think can be said
for a lot of people around me.
I really need to make a contribution
to realise myself or my potentials.
And what about
the repository's poster boy,
our second born child, Doran Blake?
He had showed such
great promise as a youngster.
I'm exceptional statistically.
You know what I mean?
I've always understood it that way.
I'm like, OK, so most people
have an IQ here and my IQ is here.
As a child, Doran was
good at everything.
"I". He was in a highly gifted
programme from first grade on.
By the time he got to Exeter,
Doran was taking existentialism and
Buddhism, and he took six separate
music lessons.
Throughout my life, I've felt like I
have not had to work as hard for the
level of achievement that I've
reached as most of my peers did.
I turned out very well.
You know, my IQ was off the charts
and is basically everything
that Robert Graham wanted.
While at least some of the children
did appear to have inherited their
donor's intelligence, the sperm
bank's success at producing geniuses
could never be fully tested.
Most of the children
remained anonymous.
Scientists continued to search
for the inherited component of
intelligence throughout the
1980s and '90s, as genetic research
became increasingly sophisticated.
But even though the genome
was fully sequenced in 2003,
no specific genes for intelligence
have yet been identified.
Behavioural geneticist
Professor Robert Plomin
has analysed the little we do
know about intelligence genes.
We don't know how many genes we're
talking about and if there are
very, very many, they're going to
have very, very small effects and
be very, very difficult to find.
But I think these genetic
differences, when they're expressed,
are going to show up
throughout the brain.
It's not going to be this gene does
that bit of the brain, this gene
affects another bit of the brain.
Now, that's a hypothesis for now but
it's a very testable one when we find
these damn genes,
if we ever do find them.
Scientists have now gathered
data from combined studies of
over 11,000 pairs of twins
to give a more up-to-date measure
of nature versus nurture.
And it shows that Galton,
Burt and Graham were at least
partly on the right track.
A large part of intelligence
is inherited.
You know, this is one of
the most highly heritable
characteristics around, intelligence.
In adults, we're talking
about at least 50 or 60%
of the variance in the population is
due to genetic differences among us.
So, if according to current
estimates, about 50%
of our intelligence is genetic,
then that of course leaves the other
half up for grabs, and that's where
environment or nurture comes in.
Scientists began to look at
the impact of everything,
from diet and supplements,
to good old pushy parenting when
fostering intelligence in children.
David Baddiel
investigated just how far
a fertile educational environment
could affect a child's abilities.
Hello.
Hello, David. Please do come in.
Hello, nice to meet you.
Hello. Hi.
Now, let's deal with...
Zaheib, the younger brother,
answers the first question.
So if this is theta...
OK, so theta is that angle?
This angle.
Right. The vertical must be T...
cos theta. That's very good. OK.
When do you first remember,
either of you, doing a maths problem?
When I was a toddler. Really tiny?
Addition. Really? Addition, yeah.
And what about you? Yeah, same.
You remember when you were
counting 99s?
Oh, yeah. In nursery,
I knew my 99 times table.
How old were you then? In nursery
you did your 99 times table? Yeah.
You were about
three-and-a-half or something.
I can't do my 99 times table! Apart
from 99 times one is 99, that's it!
Beyond that, I'm slightly struggling.
And I'm 44.
Which I think is a multiple.
No, it's not!
OK, so you are starting on A level
maths now? Yeah. It is that right?
Yes. And when are you planning to
take your A level maths? In January.
And what's very special about that?
If I get A,
I'll break the world record.
You'll be the youngest...
Ever. Ever, ever.
Child ever to get A level maths.
Why has it become important to you
to push your children?
Why is that important to you?
To give them something to think
about so that their mind is engaged
in something useful all the time.
Right. It's very important for
them to be independent thinker.
So do you feel that mathematics
specifically is almost a spiritual
training, then, for kids, in that it
will actually train their brains and
their minds to become better
thinkers, better opinion formers?
Is that what you're saying?
That's exactly right because
I did mention maths
is the key thinking tool.
Most of the time, they are
not actually studying.
So how much time do they spend?
When they don't go to school,
they spend on average
about five hours. Right.
During school days,
about three hours.
So they'll have their school day and
then another three hours of study?
Yes, yeah, on average.
It seems quite a lot to me.
But that means most
of the time they are not studying.
Because there are
24 hours in the interval.
Yeah, but then they're sleeping
for quite a lot of that.
Yes, sleeping, yes.
But it isn't just a highly
educational environment that
can enhance intelligence.
Baddiel also looked at a revealing
experiment which showed that
other behaviours instilled in very
early childhood can predict a great
deal about future academic success.
Now, if you had to choose
the one marshmallow or the
three marshmallows,
which one do you prefer?
The three marshmallows? OK.
40 years ago, a rather extraordinary
experiment was carried out in this
nursery at Stanford University.
The nursery is re-running
the experiment for David.
All it consists of is a bell,
a group of four-year-old children
and a plate of marshmallows.
The question is,
can a child resist eating the
one marshmallow in front of them for
the promise of getting three later?
If they don't want to wait the time,
they can ring the bell.
It's like watching a
primeval battle between man
or woman and their own desire.
The waiting time is ten minutes,
just five minutes shorter
than in the original.
First to go is Bridie.
See, she's now thinking,
when's he coming back?
See, I'm not absolutely
convinced that she is now
thinking about the marshmallows.
I think she might be thinking about
whatever, kid's thoughts, now.
Now she's thinking about
the marshmallows.
If Bridie is going
to succeed, she will have to devise
strategies like the children in the
original study, to look away
or stop thinking about the taste
and smell of the marshmallow.
Just 30 seconds to go
and Bridie is still resisting.
I'm feeling a bit sorry for her now.
Ooh. Oh-oh.
She's gone for the bell,
she's gone for the bell.
Is she ringing or is she
just looking at the bell?
Now she's rung the bell, she rang the
bell. I'm so disappointed for her.
Next up is Olivia.
God, has she eaten one?
Oh, my God, she's eaten a marshmallow
before the experiment's started.
But that's ruined it.
That's a shame because she's clearly
one with impulse control issues.
So it's over to Jayden.
I think I know which way she's going
to go, I tell you.
Finally, it's Keira.
Welcome back to Stanford for round
two of the marshmallow experiment.
At first, she seems
to be losing heart.
I think she can't bear it.
I can hear the devil on her shoulder
saying, "eat the marshmallow!"
This must seem so long
if you're a child.
If you think that children
have a relative idea of time that is
about ten times that of an adult.
Some of the children who'd succeeded
before had managed to stop thinking
about the marshmallow
as a real marshmallow.
They'd imagined it away.
I wonder if she's actually
consciously thought, if
I don't look at them,
I won't desire them so much.
So therefore I'll be
able to get through it.
She did it! She did it!
She did it. I'm so pleased for her.
The scientists tracked the lives of
the original children for 40 years.
What they found was that those who
could resist the marshmallow
did better at school.
And not only that, they were less
likely to fall ill, or get divorced.
It seems being able to resist a
sweet at four could predict academic
success and a happier adult life.
This experiment serves as just
one example of the traits
which can be affected by nurture.
Now, after decades of scrutinising
human intelligence, we are beginning
to understand that it can be
affected by many variables,
not only by who your parents are,
but also the environmental
influences on your upbringing.
And it's not just the causes of
intelligence that are wide-ranging.
We're also beginning to broaden our
definition of intelligence itself.
100 years ago, it was simple.
Intelligence was a measure of
problem solving ability,
general knowledge and memory
that could be assessed by one
all-encompassing test.
But now we have to look again at
whether that stood the test of time.
The IQ test has lasted so long
because it's got an almost magical
property.
It seems to show that we have one
general all-round ability, a kind of
all-purpose thinking skill that can
be represented by a single number,
the IQ score.
Very convenient, if you
want to compare people.
Horizon brought together seven
experts from seven very different
disciplines to sit the test.
The IQ test consists of many
sections that seem unconnected.
What does an entomologist study?
There are sections on vocabulary
and general knowledge.
What's the capital of Jordan?
Amman. What's the distance between
London and Hong Kong in miles?
I would suspect it's around a
third of the way around the
globe, so about 8,000 miles.
A section on memory.
Eight, one, seven, five, backwards.
Five, seven, one, eight.
And a section to
test spatial ability.
You're doing just fine.
Wow, that was tough.
Do a lot of people get
this one in two minutes?
I can't see how that works.
Common sense might tell us that
we're good at some of these sections
and bad at others.
But that's not the case.
On average, if we're good at
one of these sections,
we tend to be good at all of them.
And from this comes the idea
that intelligence is some kind
of general, all-round ability.
Based on a range of difficult
IQ problems, the results were
predictable. Well, almost.
In third place, fighter pilot, Gary.
In second place,
IQ specialist, Nathan.
But he was beaten to the top spot
by quantum physicist, Seth Lloyd.
But when the winner was announced,
there was an immediate objection.
So I'd actually like to say this
is unfair because actually these
tests were things that
fit extremely closely with what
I do on a day-to-day basis.
Seth's modesty at coming top in the
IQ-type problems shows why some
people think the IQ test is flawed.
That means the electron,
in some funky quantum sense,
reads zero and one at the same time.
Was Seth good at the tests merely
because of what he does every day?
My job consists of
trying to solve hard mathematical
problems related to the physical
world, like, you know, how does a
black hole evaporate, for instance.
I'm constantly pushed to the very
edge of what I can actually do.
So, it's actually fun for me
to do something like these
puzzles which are relatively easy.
Or did the tests capture
something essential about Seth?
We could say he has a high general
intelligence as revealed by the
tests, and that this means
he's the most intelligent.
But that's not the whole story.
Not even test manufacturers would
say the result of this test will tell
you how intelligent somebody is.
They would say it's a small
component of making those
judgments and that you should be
looking at a much broader spectrum of
skills, abilities and aptitudes.
The IQ test looks at a lot of old
knowledge, like, you know what the
capital of Italy is, or, can you add
two-plus-four, can you
compare slavery and freedom,
those are IQ-kinds of tests.
But they don't tell you anything
about whether the person will
actually ever do anything
that's productive in the world.
Professor Howard Gardner
has come up with a newer,
broader way of testing intelligence.
The major move I've made in
the study of intelligence
is to pluralise it.
I've come up with an
alternative view which is called
multiple intelligence theory.
To perform some kind of an
action in the area of music,
or in the area of navigation
is very different than to perform
in a scholastic kind of assignment.
And my whole analysis over many
years suggests it's a mistake.
It's a category error
to lump all these together
and to call them intelligence.
Professor Gardner is convinced
we have at least eight
relatively separate intelligences.
This is completely opposite to IQ,
which assumes that we all have just
one general intelligence.
So, you might be wonderful
at understanding other people
but a disaster at doing crossword
puzzles, or flying an airplane.
So we do know that an individual's
high-performance in one area
simply doesn't predict
high performance in other areas.
Horizon put its line-up of
high-flyers through Professor
Gardner's new intelligence tests
to see if the outcome would be any
different to the standard IQ tests.
But there's no agreed system
for measuring them.
This could be a drawback for
Professor Gardner's approach,
but he still defends the value
of non-academic intelligences.
Wow, this collapsed.
Football players may well not be
scholastically intelligent
and so they
don't do well in a school with
reading and writing and so on.
If we lived
in a non-literate society,
the people who do well in school
would not emerge at all, and perhaps
people who are good at football
would be better hunters, and better
strategists about survival, and
then we'd be calling them smart.
And the people who had the
potential to read and write
would be irrelevant because there'd
been no reading and writing there.
Based on the combined
outcomes of the IQ tests
and the newer intelligence tests,
the results should reveal
who has the most mental flexibility
and all-round intelligence.
Tied equal in third place,
fighter pilot, Gary,
and musical prodigy, Alex.
In second place,
IQ specialist, Nathan.
And in first place,
an interesting tie.
One of the winners did fantastically
well on the standard IQ test,
but the other one wasn't
even in the IQ test top three.
Taken across all the tests, quantum
physicist, Seth Lloyd, shared higher
scores with dramatist, Bonnie Greer.
Horizon's assessment of the
experts show that the IQ test
only identifies a very
particular type of intelligence.
It couldn't predict how
good someone would be at a
wider ranging set of skills.
But the IQ test hasn't
been consigned to the
history books just yet.
It might not pinpoint everyone's
unique intelligence type, but it
has turned out to be useful in a
way no-one could have predicted.
You have 45 minutes
to do the test, OK?
OK.
Write the three letters
between A and E.
And cross out of the middle one.
Bill and Davina are 79 years old.
This is the second time
they've done this test.
If H comes before K, write X,
unless S comes before Q...
The first time was in 1932 when
every 11-year-old in Scotland was
put through an intelligence test.
The results were rediscovered
recently in an Edinburgh basement.
If you want to know how our
intelligence changes as we
get older, these results
are a potential goldmine.
We've brought hundreds of people
back and we got them to sit the exact
same test they had sat
when they were aged 11.
Now, these people were now
79 or 80 years old.
We gave the same instructions,
we gave the same test,
and we gave the same time limit.
It was a little stickier
than I thought it would be.
I walked through it quite happily,
quite honestly.
I felt I must have been very bright
at 11 if I sat that exam and passed.
There were some intriguing results.
Almost everyone had a better score
at 80 than they did at 11.
But some had gone from being
just averagely intelligent
to a much higher level.
Now that's what really drives
our research.
Why are those people who've gone from
IQ 100 at age 11, up to 110 or 120?
What have they done right? What can
be the recipe for successful ageing?
We're finding that
the person with more education,
even though they had the same IQ in
childhood, is doing slightly better
in old age, on average.
The person who had
a more professional job
in old age is doing slightly
better, on average, than the person
who had a manual job despite the fact
that they started at the same level.
The people who smoked
have got slightly less good
mental ability than you would expect.
What's even more remarkable is that
the kids who had higher IQ scores at
11 are the very ones
still alive today.
So it seems high IQ in
childhood is good for survival.
Maybe an IQ score is a record of how
well wired together your brain is,
and that might, highly speculative,
that might be associated
with how well wired up
the rest of your body is.
But if our intelligence can increase
as we grow older, can we go one step
further and boost it artificially?
Marcus du Sautoy
investigated one technique.
At the University of Goettingen
in Germany, they're pioneering
technology that could greatly extend
our control over our own brains.
They're developing a means
to turbo-charge our grey matter.
The aim is to improve the volunteer's
ability to subconsciously learn.
The test itself is simple.
When Leila sees a dot appear on
the screen, she has to tap a
corresponding key on the keyboard.
There is a pattern to
when the dots appear.
But it's impossible to detect.
At least before the artificial
stimulation of her brain begins.
What we want to do
is to facilitate the
excitability of her motor cortex.
And in order to be able to do that,
we have to fix an electrode.
I presume this is perfectly safe.
I mean, I'd be a bit nervous
about having electricity
shot through my brain.
Well, they're very weak currents.
They're so weak,
she doesn't notice anything.
They're so weak that they just
manipulate the membrane potential
of nerve cells a little bit.
So, now we will stimulate
the motor cortex here.
By anodal electricity, positive
electricity, for 10 minutes.
So, now stimulation starts.
So there's now electricity
passing through Leila's brain.
Can you feel anything? No, nothing.
There's no smoke. I can't see any.
And during this stimulation,
Leila will move her fingers and do
the implicit learning paradigm.
Then we will measure simultaneously
how quick she can respond to
the visual target during this time.
What we expect to see is with motor
cortex depolarisation
that's more excitable
and then her reaction time
will improve.
And then we'll see
an increase in speed that she's not
constantly picking up a pattern, but
subconsciously,
she's getting better at learning.
The longer the stimulation lasts,
the greater its effects will be.
In previous experiments lasting 24
hours, permanent improvements
to the brain were forged.
We know from other research,
basic animal research, that
new connections between
individual nerve cells will be built
after about 30 minutes.
And after about a day,
they start to become functional.
So it's really changing the structure
of the brain by doing this? Yes.
It's not just a temporary effect?
Yes, so we have structural
alterations which allow you to move
your fingers quicker in this case.
With measuring the reaction times,
we will see that you'll probably
speed up in the range of 10% or so.
10%, and that's significant, is it?
10%, you wouldn't expect that?
Not without stimulation. Right.
The idea of being able to enhance
our intelligence, if you don't mind
having your brain stimulated, hints
at the dawn of a brave new world.
But if you're going to involve
computers, then why stop there?
Some scientists think the creation
of artificial intelligence
could transport us to new levels
of interaction and understanding.
It's something that has occupied the
minds of technology researchers
for decades,
and Horizon has featured
some of their wilder predictions.
Our descendant will not
be the child of the loin,
but the child of the brains,
the thing we call the computer,
which does not have to pass
through the birth canal.
And does not grow by a tablespoonful
of grey matter every 100,000 years,
which is the case in the rapid growth
of our brain,
but grows a factor
of 10 in power every seven years.
The computer generation.
There's no question that it'll match
us in narrow reasoning power by 1990,
and go beyond us to become the great
new intelligent race of the future.
The artificial intelligences of
the future will be worried about
weighty problems that we
simply can't understand.
And they may condescend
to talk to us. They may...
amuse us on occasion, or play
games that we like to play.
And in some sense,
they might keep us as pets.
Although those predictions haven't
been borne out, work on artificial
intelligence has continued to race
towards the goal of a man-made
super-intelligence, leading one
man to predict that a computer will
equal a human brain's power by 2029.
His name is Ray Kurzweil,
inventor and visionary.
He believes that our
understanding of the human brain
will soon be complete.
25 years from now, we will
have actually mastered
human intelligence.
We'll have both the hardware
and the software to recreate
human intelligence in a machine.
Kurzweil was one of the first to
make a computer that could read.
MACHINE: 'For score and seven years
ago, our fathers brought forth
upon this...'
If his latest prediction is right,
then we will understand
the human brain
at almost exactly the same time
as computers equal its power.
It's this culmination of events
that would lead to the singularity.
There's really a point in human
history where human society will be
profoundly transformed by creating
non-biological intelligence.
Machines that are ultimately
billions of times more capable
than human beings today.
And we will integrate with
this technology, and it will enhance
human potential.
We'll have to wait until 2029
to find out whether Kurzweil's
prediction is correct.
Until then, science can only
continue in its quest to fully
fathom our unique mental abilities.
Understanding what makes my
intelligence different from
that of someone like Einstein's
could be a question of my genes,
or the way I was brought up.
Maybe I'm just intelligent
in a different kind of way?
He was pretty good at physics.
I'm pretty good at...
Well, anyway,
2029 is not so far away
so maybe we'll just have to wait
and see who's so clever then.
8175 backwards?
5718.
What does an entomologist study?
Wow! That was tough. Did a lot of
people get this one in two minutes?
And why do some people apparently
have so much more of it than others?
Where does intelligence come from?
Is it a matter of luck, biology
or just a good education that
makes this guy cleverer than me?
Is there anything that I
or my parents could have done
to make me more intelligent?
Well, scientists have been battling
thorny questions like these for
decades, making intelligence one of
the most studied traits in science.
But it's only really now that we
are beginning to get some answers.
For nearly 50 years,
Horizon has been following
that search to understand
our mysterious mental power,
looking at everything from
our evolutionary history to whether
a computer could outsmart us.
And asking the questions,
how do you test for intelligence?
Is it inherited or innate?
Nature or nurture?
In so doing, science has begun
to redefine our understanding of
what makes every one of us unique.
The benchmark for measuring one
person's intelligence against
another is the iconic IQ or
Intelligence Quotient test.
Most of us will have sat through
one of these at one time or another.
It is the dreaded IQ test, with
sections on spatial awareness,
general knowledge and reasoning.
And it tots up different areas
of skill to create one score.
A single mark that can brand you
with either a low, high
or maybe an average IQ.
Now, we've been judged on the
merits of this test for years now.
What's remarkable about it
is that it was introduced in 1912.
So, essentially, this has remained
the same for almost 100 years.
In 2006, Horizon tested the IQs
of seven experts in their field
to see who would come out on top.
Seven people from seven
very different backgrounds.
All highly successful.
And all seven prepared to do battle
over the elusive nature
of intelligence.
The test lasts 30 minutes.
What it revealed would show how our
understanding of intelligence
has changed since the IQ test
was first devised.
We have spent 100 years on
IQ tests that are basically the same.
Imagine if physics or chemistry or
medicine or biology were the same
today as they were 100 years ago.
That's essentially the state
of the testing industry.
It's unusual to find a methodology
that has changed so little.
And perhaps this reflects the
century-long struggle to work out
how intelligence develops.
In their bid to understand human
intelligence, scientists have looked
for evidence of it in other animals.
During the 1980s,
Dr James Gould searched for
signs of intelligent behaviour
in the complex lives of bees.
Even now, when I look at bees,
it's hard to imagine that these tiny,
nervous little insects
could be intelligent.
Yet, in all this apparent
chaos, there is a
tremendous amount of order.
Bees are not behaving randomly, they
are going about the task of solving
a series of specific problems.
They spend the first few days feeding
the queen and taking care of her.
And then they spend a few days
building honeycomb in the hive.
And then a few days
guarding the hive's entrance and
then, finally, several weeks
gathering food from flowers.
These are all clever things and yet
this behaviour is driven
by biological cues.
All through the life of a bee,
an innate sensitivity to certain cues
helps guide its behaviour.
And this is by no means an exception,
this is the rule in the animal world.
And it makes sense, too.
If the behaviour is sufficiently
predictable and the cues are
sufficiently predictable,
it makes sense for an animal not
to reason out what it ought to do,
but to simply respond automatically.
A good example of this is
tits open milk bottles
because instinctively they peel
back bark to look for grubs.
Gould concluded that, unlike humans,
the short lifespans of many insects
and animals means they simply don't
have enough time to work
out solutions to problems.
Their apparently intelligent
behaviour is just a response to
a series of biological cues.
However, there are animals that
do appear to display a capacity
for intelligent problem-solving.
Research into one species -
chimpanzees - has begun to
reveal greater capabilities
that go beyond pure instinct.
Writer, Danny Wallace,
went to Uganda to find out more.
He was keen to investigate
an experiment to test a chimp's
ability to solve a complex problem.
This box of bananas placed away
from the cage poses a tricky problem.
Ah.
I see what you've done.
'To get the bananas to come
towards me, I would have to pull
both ends of the rope.
'But they were too far apart.'
Right, OK. I can't.
Diana?
Will you be another chimp, please?
Chimp-cam.
'I could see that if
I didn't get Diana involved,
I'd get no bananas at all.
'And that didn't bear
thinking about.'
One, two, three.
We did it, we got the bananas.
Now for the chimps.
Chimp one has a rational choice.
Share the bananas with chimp two
or get no banana at all.
Three, two, one. Release the chimp.
OK. So, he's going a bit mad.
Chimp one can't get the bananas.
Chimp two is going mad, chimp
one is wondering what's going on.
Oh, he has let him out.
That's amazing.
That's incredible.
Chimp one, he's very happy,
and off they go.
That was brilliant.
That was quicker than me.
The chimp appeared to be
making a thoughtful decision,
suggesting that chimps are
intelligent enough to co-operate.
A key human trait.
Yet human intelligence
still sets us apart from our
closest evolutionary cousins.
Thank you for taking part
in this experiment. This is for you.
Scientists have delved
deep into our prehistoric
past to try to find out when we
developed superior intelligence.
When did our ancestors
cease being brute animals
and first become truly human?
When did we learn to think?
Thinking is the defining
trait of humankind.
It has given us machines.
Technology. Power.
No other animal has the ability
to look at the world outside
and transform it.
Where all other animals live from
day to day, we alone plan ahead.
Dream. And create.
Find the day we learned to think
and you would have identified perhaps
the single most important moment
in human history.
But it was not going to be simple.
Thinking leaves no traces.
There are no fossilised
thoughts waiting to be dug out
of the ground and dated.
It was like investigating
a murder scene without a body.
So, scientists had to
look for indirect clues.
Not fossils, but other
evidence for when thought began.
And then they realised that thought
must have come hand-in-hand
with something else.
What are we going to look for,
first of all, that's going to
give us evidence that humans
were behaving in a modern way?
So we look, in a way, for proxies.
But there was one kind of evidence
archaeologists could look for.
The obvious line of evidence is art.
When you get unquestionable art
that's widespread and common,
I think you can say you're
dealing with people just like us.
Only humans create and
can make sense of art.
I'm sure that dozens of dogs
have walked down this street
in the past years
and perhaps not a one has glanced up
in awe or wonder
and thought
to himself, what does this mean?
For a dog, this is colour on a wall.
Perhaps even less than that.
But to a human being,
a painting is far more than
just a collection of colours.
An expression of thought.
Suddenly, what they had
to look for was clear.
Discover the earliest
forms of human art
and you would have found
the day we learned to think.
At Blombos, on the east
coast of South Africa,
anthropologist Chris Henshilwood
had been quietly excavating his
prehistoric cave for over a decade.
This is Blombos cave here.
A very special find.
We're really
looking at what has been left here
almost as if it was
put down here yesterday.
As they dug down through the floor of
the cave, his team were going back to
an ancient time of human habitation
tens of thousands of years ago.
We came down onto this layer
you can see over here,
which really was quite remarkable.
On the surface were lying
the most beautifully made artefacts.
Bone points, spear points as well.
And immediately I realised we had
gone back a very long way in time.
The beautifully crafted objects
were dated to over 70,000 years ago.
But there was still not proof
the people in the cave
were thinking people,
like us.
One type of item started appearing
over and over again.
We noticed large numbers
of pieces of ochre.
8,000 pieces of ochre
in the old levels alone.
Then, one day, Henshilwood
found a piece of ochre
that was different from the rest.
We found this piece of ochre,
brushed up the side and there was
this absolutely remarkable
pattern revealed.
There was huge excitement,
you can imagine.
The ochre piece appeared to have
been marked with a clear image.
What seemed like an abstract
geometric pattern.
This was a deliberate construction
of a series of crosshatches
in each direction.
A line across the top,
a line through the middle
and a line down the bottom.
So it actually
circumscribed that engraving.
As if they had made the crosses
and deliberately surrounded it
with these other lines as well.
Here is the first example of the
ability of humans to store something
outside of the human brain.
You're storing a message
that somebody else who is part of
that same group can pick up and they
will understand what that meant.
This is the beginning of
things like art, writing
and everything else that follows.
It was the earliest
evidence of the thinking brain.
There is still much that we
don't know about the evolution
of human intelligence.
But it was during the second half of
the 19th century that the ideas of
Charles Darwin began to profoundly
influence our thinking.
Francis Galton was
the first scientist
to propose that intelligence was a
biologically-based mental faculty.
He was Darwin's cousin and was much
inspired by reading his book,
On The Origin Of Species.
Galton thought that human mental
abilities were inherited in just
the same way as the plant and
animal traits outlined by Darwin.
And he set out to prove it.
Galton was obsessed
with measuring things.
He was convinced that
everything was inherited,
from arm length to reaction time.
According to his theory, people with
bigger heads, such as himself,
would have a greater capacity
for intelligence than others.
So he started to measure the heads
of a group of Cambridge students
and compared those
measurements to the test results.
But, disappointingly for him,
the correlation between those
two sets of data was low.
The evidence simply didn't stack up.
But Galton stuck doggedly
to his conviction
that intelligence was inherited.
He coined the phrase,
"nature versus nurture",
which has proved to be one of the
most enduring questions at the
heart of the intelligence debate.
But it was Galton's disciple,
a psychologist named Cyril Burt,
whose research was to have a huge
impact on both our thinking about
and our testing of intelligence.
Horizon dramatised Burt's
youthful idealisation of Galton,
which would have
an enduring influence on his work.
Galton was one of Burt's
heroes, maybe the only one.
Of all the psychologists
whose names were mentioned
in my discussions with Burt, I
think the only one that he seemed to
talk about admiringly was Galton.
This is young Loddy, Sir Francis.
Loddy?
Loderick, sir. It's a shortening.
My first name is Cyril,
then Loderick.
Are you good at your
schoolwork, Loddy?
Oh, yes, sir. Very good.
He's a very diligent boy.
He has a diligent father.
He will have inherited
his father's intelligence.
Burt seemed to worship
Francis Galton.
He kept on mentioning the one
occasion on which he met him.
And he certainly tried to
follow in his footsteps.
Oh, no. Do you read classics?
I want to be a scientist.
Burt was particularly drawn
to one of Galton's ideas.
In 1883, Galton had coined the
term eugenics, meaning good birth.
He believed that people of high rank
had greater intelligence and should
be encouraged to marry and have
children to preserve these traits,
while the poor be strongly
discouraged from breeding.
Burt adopted this idea
with enthusiasm.
For example,
Burt has written out on his hand:
"The problem of the very poor.
"They must be segregated, prevented
from reproducing their own kind".
This is the kind of atmosphere,
obviously, to which he was exposed.
Working in the 1930s,
Burt was determined to prove
intelligence was inherited.
He brought together more evidence
for the inheritance of intelligence
than any other person
had done at that time.
His papers were more impressive
in terms of the number of different
kinds of kinships on which
heritables had been estimated.
The fine grain detail in which the
analyses were carried out. And so on.
Burt introduced the IQ test
as a way of measuring
schoolchildren's intelligence.
He was also to influence the
introduction of the 11 Plus test,
which was to become a key decider
of a child's academic future.
By 1945, every child's
intelligence was tested.
In order to study the inherited
element of intelligence,
Burt looked for subjects that were
the same in every way, except the
environment they were brought up in.
Identical twins who had
been separated at birth.
So now, if you can find, when they
are old enough to be IQ tested,
a fair number of pairs of such twins,
you can give them all IQ tests, and
if their measured IQs resemble one
another, that must be due to the only
thing they have in common, namely
their identical genetic make-up.
It cannot be due to their
environment, in theory, because
they don't have that in common.
Burt announced his findings with a
great flourish, stating that he had
found genetics were responsible
for 80% of his subjects' IQ.
In the crucial matter of
separated monozygotic twins,
and the measurement of the genetic
heritability of intelligence,
over the years we have been fortunate
enough to steadily increase our
sample size to the point where our
data, based on 52 pairs of twins,
is some 30% greater than
that of its closest rival.
Burt's research was highly respected
and in 1946 he became the first
British psychologist to be knighted
for his contributions
to psychological testing.
But his ideas on eugenics
had rather lost their appeal.
Adolf Hitler adopted this philosophy
to murder thousands of people he
labelled mentally defective.
The scientific community
began to distance itself
from the idea of engineering
society according to intelligence.
Burt continued to defend his ideas,
but it was only after his death
in 1971
that scientists, including Professor
Leon Kamin, scrutinised his results
and came to some uneasy conclusions.
As the sample size increased
progressively, in successive papers,
one noted an absolutely
incredible thing.
The correlations, the statistical
results that he reported, remained
identical to the third decimal.
Well, theoretically, that
sort of thing could happen.
Also theoretically, the sun might not
rise tomorrow morning, and that's
probably a more probable event than
what one would have
had to have believed
if one took Burt's number seriously.
All of them remain identical
to the third decimal place.
Clearly something
was drastically wrong.
There's universal agreement
among psychologists that Burt
couldn't possibly have
tested 53 pairs of twins.
That at least the last 32 pairs
must be figments of his imagination.
I take perhaps an even
more sceptical view of Burt.
I think it's reasonable to suppose
that he may never have laid eyes on
a separated twin
in his entire lifetime.
But Kamin was convinced that Burt
was motivated only by his genuine
belief in inherited intelligence.
I don't think Burt thought of himself
as a manipulator and misleader
of the public.
I think Burt had the
intellectual audacity to think
that he knew the truth prior to any
actual investigation of the facts,
and therefore on account of noblesse
oblige, he was letting the rest of
us get a handle on the truth
by presenting us numbers that
would help us to accept it.
And he did us the courtesy of
inventing the numbers for us.
Comprehensive proof of the part
genetics play in intelligence
still remained elusive,
but as the '70s got underway,
that didn't deter one man from
adopting a radical new approach.
In a rather sinister echo of
Burt and Galton's theories,
Californian doctor Robert Graham
reasoned that if there were
intelligence genes to be had, he
could find a way of passing them on.
In 2006, after Graham's death,
Horizon looked back at
his extraordinary quest.
My name is Robert Klark Graham
and I had a dream.
To single-handedly saved the
human race, one child at a time.
Robert Graham believed that the gene
pool was going downhill and that
we needed to do something about that.
He had this grandiose plan
to remake all of humanity.
It had the air of James Bond movie
meets Disney, or something.
Using the sperm of clever men,
I hope to create intelligent kids.
He was this strange scientist
that was trying to breed
the super race.
What we're doing is exploring
the possibilities of genetics.
I was accused of being a racist
and a Nazi.
I can't say that I know much
about Hitler or his vision.
Yet my sperm bank was
operational for nearly 20 years.
Despite tremendous controversy,
I was responsible for the
creation of over 200 children.
I would not be here without Robert
Graham, without his existence, and
in a way, I owe him my life.
Well, I'm Tom Grunwal, and live here
in Temecula in southern California.
I'm Andrea Grunwal
and I live with Tom.
I had had two children
with my first wife,
then with my second wife, I
took the steps to have a vasectomy.
The next thing you know,
I'm divorced.
I never really thought I
would ever have another child
in the rest of my life.
Until I met Andrea.
I finally just spilled my gut
and said, Tom, I don't know
how to say this, but I would really
like to have a baby and I don't
know how you feel about that.
And I said,
OK, if you can figure out how,
let's go for it.
I wanted to offer these women
the seed of clever men,
and for me, scientists
were the pinnacle of intelligence.
With proven, measurable,
practical ability.
I figured, let's start at the top.
We were trying to have
outstanding genes and Nobel Prize
winners possessed them.
Due to your outstanding
achievements, you
would be an excellent donor for our
Repository for Germinal Choice.
We hope to create some very bright
children, possibly a genius or two.
I managed to convince three Nobel
laureate scientists to each provide
an anonymous sample for my bank.
I actually was a little surprised
that some of these older fellows were
able to produce specimens so quickly.
Bob was very pleased when we
took that first look at the
specimen under the microscope and saw
thousands of sperm
swimming vigorously.
He beamed with joy.
Good job!
It's peculiar, but
I didn't think it was weird.
My name is Dr Afton Blake
and I live in Los Angeles,
California, in a little place
called Mount Washington.
Om....
When I first called the repository,
they were very friendly.
They came up the next day
to meet me and interview me.
And I think the very next month
I tried my first insemination.
Choose me as your mother.
Then, 10 months after I had
tried the first time, I conceived.
In August 1982,
having been impregnated with donor
codenamed Red 28, Dr Afton Blake
gave birth to a boy she named Doran.
It was ecstasy from
the moment he came out, looked in my
eyes, and stopped crying,
immediately that we made contact
and the bond was like so incredible.
Everybody liked the name Doran, which
means in Greek, a gift from the gods.
I could never imagine life
without him. It was like suddenly,
what did I have before I had Doran?
I didn't know,
because this was everything.
Do you want to hand me the dog?
I am immensely pleased with
the outcome of the mating
between Dr Blake and Number 28.
We've had a splendid result.
I think no question about it.
Doran is about as ideal, as nearly
as we can judge at his early age,
about as ideal as we could hope.
Everyone wanted to know about
my genius sperm bank child.
Doran represented what
Dr Graham was trying to achieve.
Smart, beautiful.
Everybody wanted a Doran.
They just wanted to come to
our bank and get a Doran.
The phone rang off the hook.
We had arrived.
After 20 years in operation,
my genius sperm bank was
ultimately responsible for
the production of 217 children.
We've got lots of baby pictures.
Jessie ended up being the 15th
baby born to the repository.
People used to just be amazed
at his abilities.
I look at myself as being an
intelligent person and I think that
I'm achieving in the world
all that I can achieve.
And that's something that
I don't think can be said
for a lot of people around me.
I really need to make a contribution
to realise myself or my potentials.
And what about
the repository's poster boy,
our second born child, Doran Blake?
He had showed such
great promise as a youngster.
I'm exceptional statistically.
You know what I mean?
I've always understood it that way.
I'm like, OK, so most people
have an IQ here and my IQ is here.
As a child, Doran was
good at everything.
"I". He was in a highly gifted
programme from first grade on.
By the time he got to Exeter,
Doran was taking existentialism and
Buddhism, and he took six separate
music lessons.
Throughout my life, I've felt like I
have not had to work as hard for the
level of achievement that I've
reached as most of my peers did.
I turned out very well.
You know, my IQ was off the charts
and is basically everything
that Robert Graham wanted.
While at least some of the children
did appear to have inherited their
donor's intelligence, the sperm
bank's success at producing geniuses
could never be fully tested.
Most of the children
remained anonymous.
Scientists continued to search
for the inherited component of
intelligence throughout the
1980s and '90s, as genetic research
became increasingly sophisticated.
But even though the genome
was fully sequenced in 2003,
no specific genes for intelligence
have yet been identified.
Behavioural geneticist
Professor Robert Plomin
has analysed the little we do
know about intelligence genes.
We don't know how many genes we're
talking about and if there are
very, very many, they're going to
have very, very small effects and
be very, very difficult to find.
But I think these genetic
differences, when they're expressed,
are going to show up
throughout the brain.
It's not going to be this gene does
that bit of the brain, this gene
affects another bit of the brain.
Now, that's a hypothesis for now but
it's a very testable one when we find
these damn genes,
if we ever do find them.
Scientists have now gathered
data from combined studies of
over 11,000 pairs of twins
to give a more up-to-date measure
of nature versus nurture.
And it shows that Galton,
Burt and Graham were at least
partly on the right track.
A large part of intelligence
is inherited.
You know, this is one of
the most highly heritable
characteristics around, intelligence.
In adults, we're talking
about at least 50 or 60%
of the variance in the population is
due to genetic differences among us.
So, if according to current
estimates, about 50%
of our intelligence is genetic,
then that of course leaves the other
half up for grabs, and that's where
environment or nurture comes in.
Scientists began to look at
the impact of everything,
from diet and supplements,
to good old pushy parenting when
fostering intelligence in children.
David Baddiel
investigated just how far
a fertile educational environment
could affect a child's abilities.
Hello.
Hello, David. Please do come in.
Hello, nice to meet you.
Hello. Hi.
Now, let's deal with...
Zaheib, the younger brother,
answers the first question.
So if this is theta...
OK, so theta is that angle?
This angle.
Right. The vertical must be T...
cos theta. That's very good. OK.
When do you first remember,
either of you, doing a maths problem?
When I was a toddler. Really tiny?
Addition. Really? Addition, yeah.
And what about you? Yeah, same.
You remember when you were
counting 99s?
Oh, yeah. In nursery,
I knew my 99 times table.
How old were you then? In nursery
you did your 99 times table? Yeah.
You were about
three-and-a-half or something.
I can't do my 99 times table! Apart
from 99 times one is 99, that's it!
Beyond that, I'm slightly struggling.
And I'm 44.
Which I think is a multiple.
No, it's not!
OK, so you are starting on A level
maths now? Yeah. It is that right?
Yes. And when are you planning to
take your A level maths? In January.
And what's very special about that?
If I get A,
I'll break the world record.
You'll be the youngest...
Ever. Ever, ever.
Child ever to get A level maths.
Why has it become important to you
to push your children?
Why is that important to you?
To give them something to think
about so that their mind is engaged
in something useful all the time.
Right. It's very important for
them to be independent thinker.
So do you feel that mathematics
specifically is almost a spiritual
training, then, for kids, in that it
will actually train their brains and
their minds to become better
thinkers, better opinion formers?
Is that what you're saying?
That's exactly right because
I did mention maths
is the key thinking tool.
Most of the time, they are
not actually studying.
So how much time do they spend?
When they don't go to school,
they spend on average
about five hours. Right.
During school days,
about three hours.
So they'll have their school day and
then another three hours of study?
Yes, yeah, on average.
It seems quite a lot to me.
But that means most
of the time they are not studying.
Because there are
24 hours in the interval.
Yeah, but then they're sleeping
for quite a lot of that.
Yes, sleeping, yes.
But it isn't just a highly
educational environment that
can enhance intelligence.
Baddiel also looked at a revealing
experiment which showed that
other behaviours instilled in very
early childhood can predict a great
deal about future academic success.
Now, if you had to choose
the one marshmallow or the
three marshmallows,
which one do you prefer?
The three marshmallows? OK.
40 years ago, a rather extraordinary
experiment was carried out in this
nursery at Stanford University.
The nursery is re-running
the experiment for David.
All it consists of is a bell,
a group of four-year-old children
and a plate of marshmallows.
The question is,
can a child resist eating the
one marshmallow in front of them for
the promise of getting three later?
If they don't want to wait the time,
they can ring the bell.
It's like watching a
primeval battle between man
or woman and their own desire.
The waiting time is ten minutes,
just five minutes shorter
than in the original.
First to go is Bridie.
See, she's now thinking,
when's he coming back?
See, I'm not absolutely
convinced that she is now
thinking about the marshmallows.
I think she might be thinking about
whatever, kid's thoughts, now.
Now she's thinking about
the marshmallows.
If Bridie is going
to succeed, she will have to devise
strategies like the children in the
original study, to look away
or stop thinking about the taste
and smell of the marshmallow.
Just 30 seconds to go
and Bridie is still resisting.
I'm feeling a bit sorry for her now.
Ooh. Oh-oh.
She's gone for the bell,
she's gone for the bell.
Is she ringing or is she
just looking at the bell?
Now she's rung the bell, she rang the
bell. I'm so disappointed for her.
Next up is Olivia.
God, has she eaten one?
Oh, my God, she's eaten a marshmallow
before the experiment's started.
But that's ruined it.
That's a shame because she's clearly
one with impulse control issues.
So it's over to Jayden.
I think I know which way she's going
to go, I tell you.
Finally, it's Keira.
Welcome back to Stanford for round
two of the marshmallow experiment.
At first, she seems
to be losing heart.
I think she can't bear it.
I can hear the devil on her shoulder
saying, "eat the marshmallow!"
This must seem so long
if you're a child.
If you think that children
have a relative idea of time that is
about ten times that of an adult.
Some of the children who'd succeeded
before had managed to stop thinking
about the marshmallow
as a real marshmallow.
They'd imagined it away.
I wonder if she's actually
consciously thought, if
I don't look at them,
I won't desire them so much.
So therefore I'll be
able to get through it.
She did it! She did it!
She did it. I'm so pleased for her.
The scientists tracked the lives of
the original children for 40 years.
What they found was that those who
could resist the marshmallow
did better at school.
And not only that, they were less
likely to fall ill, or get divorced.
It seems being able to resist a
sweet at four could predict academic
success and a happier adult life.
This experiment serves as just
one example of the traits
which can be affected by nurture.
Now, after decades of scrutinising
human intelligence, we are beginning
to understand that it can be
affected by many variables,
not only by who your parents are,
but also the environmental
influences on your upbringing.
And it's not just the causes of
intelligence that are wide-ranging.
We're also beginning to broaden our
definition of intelligence itself.
100 years ago, it was simple.
Intelligence was a measure of
problem solving ability,
general knowledge and memory
that could be assessed by one
all-encompassing test.
But now we have to look again at
whether that stood the test of time.
The IQ test has lasted so long
because it's got an almost magical
property.
It seems to show that we have one
general all-round ability, a kind of
all-purpose thinking skill that can
be represented by a single number,
the IQ score.
Very convenient, if you
want to compare people.
Horizon brought together seven
experts from seven very different
disciplines to sit the test.
The IQ test consists of many
sections that seem unconnected.
What does an entomologist study?
There are sections on vocabulary
and general knowledge.
What's the capital of Jordan?
Amman. What's the distance between
London and Hong Kong in miles?
I would suspect it's around a
third of the way around the
globe, so about 8,000 miles.
A section on memory.
Eight, one, seven, five, backwards.
Five, seven, one, eight.
And a section to
test spatial ability.
You're doing just fine.
Wow, that was tough.
Do a lot of people get
this one in two minutes?
I can't see how that works.
Common sense might tell us that
we're good at some of these sections
and bad at others.
But that's not the case.
On average, if we're good at
one of these sections,
we tend to be good at all of them.
And from this comes the idea
that intelligence is some kind
of general, all-round ability.
Based on a range of difficult
IQ problems, the results were
predictable. Well, almost.
In third place, fighter pilot, Gary.
In second place,
IQ specialist, Nathan.
But he was beaten to the top spot
by quantum physicist, Seth Lloyd.
But when the winner was announced,
there was an immediate objection.
So I'd actually like to say this
is unfair because actually these
tests were things that
fit extremely closely with what
I do on a day-to-day basis.
Seth's modesty at coming top in the
IQ-type problems shows why some
people think the IQ test is flawed.
That means the electron,
in some funky quantum sense,
reads zero and one at the same time.
Was Seth good at the tests merely
because of what he does every day?
My job consists of
trying to solve hard mathematical
problems related to the physical
world, like, you know, how does a
black hole evaporate, for instance.
I'm constantly pushed to the very
edge of what I can actually do.
So, it's actually fun for me
to do something like these
puzzles which are relatively easy.
Or did the tests capture
something essential about Seth?
We could say he has a high general
intelligence as revealed by the
tests, and that this means
he's the most intelligent.
But that's not the whole story.
Not even test manufacturers would
say the result of this test will tell
you how intelligent somebody is.
They would say it's a small
component of making those
judgments and that you should be
looking at a much broader spectrum of
skills, abilities and aptitudes.
The IQ test looks at a lot of old
knowledge, like, you know what the
capital of Italy is, or, can you add
two-plus-four, can you
compare slavery and freedom,
those are IQ-kinds of tests.
But they don't tell you anything
about whether the person will
actually ever do anything
that's productive in the world.
Professor Howard Gardner
has come up with a newer,
broader way of testing intelligence.
The major move I've made in
the study of intelligence
is to pluralise it.
I've come up with an
alternative view which is called
multiple intelligence theory.
To perform some kind of an
action in the area of music,
or in the area of navigation
is very different than to perform
in a scholastic kind of assignment.
And my whole analysis over many
years suggests it's a mistake.
It's a category error
to lump all these together
and to call them intelligence.
Professor Gardner is convinced
we have at least eight
relatively separate intelligences.
This is completely opposite to IQ,
which assumes that we all have just
one general intelligence.
So, you might be wonderful
at understanding other people
but a disaster at doing crossword
puzzles, or flying an airplane.
So we do know that an individual's
high-performance in one area
simply doesn't predict
high performance in other areas.
Horizon put its line-up of
high-flyers through Professor
Gardner's new intelligence tests
to see if the outcome would be any
different to the standard IQ tests.
But there's no agreed system
for measuring them.
This could be a drawback for
Professor Gardner's approach,
but he still defends the value
of non-academic intelligences.
Wow, this collapsed.
Football players may well not be
scholastically intelligent
and so they
don't do well in a school with
reading and writing and so on.
If we lived
in a non-literate society,
the people who do well in school
would not emerge at all, and perhaps
people who are good at football
would be better hunters, and better
strategists about survival, and
then we'd be calling them smart.
And the people who had the
potential to read and write
would be irrelevant because there'd
been no reading and writing there.
Based on the combined
outcomes of the IQ tests
and the newer intelligence tests,
the results should reveal
who has the most mental flexibility
and all-round intelligence.
Tied equal in third place,
fighter pilot, Gary,
and musical prodigy, Alex.
In second place,
IQ specialist, Nathan.
And in first place,
an interesting tie.
One of the winners did fantastically
well on the standard IQ test,
but the other one wasn't
even in the IQ test top three.
Taken across all the tests, quantum
physicist, Seth Lloyd, shared higher
scores with dramatist, Bonnie Greer.
Horizon's assessment of the
experts show that the IQ test
only identifies a very
particular type of intelligence.
It couldn't predict how
good someone would be at a
wider ranging set of skills.
But the IQ test hasn't
been consigned to the
history books just yet.
It might not pinpoint everyone's
unique intelligence type, but it
has turned out to be useful in a
way no-one could have predicted.
You have 45 minutes
to do the test, OK?
OK.
Write the three letters
between A and E.
And cross out of the middle one.
Bill and Davina are 79 years old.
This is the second time
they've done this test.
If H comes before K, write X,
unless S comes before Q...
The first time was in 1932 when
every 11-year-old in Scotland was
put through an intelligence test.
The results were rediscovered
recently in an Edinburgh basement.
If you want to know how our
intelligence changes as we
get older, these results
are a potential goldmine.
We've brought hundreds of people
back and we got them to sit the exact
same test they had sat
when they were aged 11.
Now, these people were now
79 or 80 years old.
We gave the same instructions,
we gave the same test,
and we gave the same time limit.
It was a little stickier
than I thought it would be.
I walked through it quite happily,
quite honestly.
I felt I must have been very bright
at 11 if I sat that exam and passed.
There were some intriguing results.
Almost everyone had a better score
at 80 than they did at 11.
But some had gone from being
just averagely intelligent
to a much higher level.
Now that's what really drives
our research.
Why are those people who've gone from
IQ 100 at age 11, up to 110 or 120?
What have they done right? What can
be the recipe for successful ageing?
We're finding that
the person with more education,
even though they had the same IQ in
childhood, is doing slightly better
in old age, on average.
The person who had
a more professional job
in old age is doing slightly
better, on average, than the person
who had a manual job despite the fact
that they started at the same level.
The people who smoked
have got slightly less good
mental ability than you would expect.
What's even more remarkable is that
the kids who had higher IQ scores at
11 are the very ones
still alive today.
So it seems high IQ in
childhood is good for survival.
Maybe an IQ score is a record of how
well wired together your brain is,
and that might, highly speculative,
that might be associated
with how well wired up
the rest of your body is.
But if our intelligence can increase
as we grow older, can we go one step
further and boost it artificially?
Marcus du Sautoy
investigated one technique.
At the University of Goettingen
in Germany, they're pioneering
technology that could greatly extend
our control over our own brains.
They're developing a means
to turbo-charge our grey matter.
The aim is to improve the volunteer's
ability to subconsciously learn.
The test itself is simple.
When Leila sees a dot appear on
the screen, she has to tap a
corresponding key on the keyboard.
There is a pattern to
when the dots appear.
But it's impossible to detect.
At least before the artificial
stimulation of her brain begins.
What we want to do
is to facilitate the
excitability of her motor cortex.
And in order to be able to do that,
we have to fix an electrode.
I presume this is perfectly safe.
I mean, I'd be a bit nervous
about having electricity
shot through my brain.
Well, they're very weak currents.
They're so weak,
she doesn't notice anything.
They're so weak that they just
manipulate the membrane potential
of nerve cells a little bit.
So, now we will stimulate
the motor cortex here.
By anodal electricity, positive
electricity, for 10 minutes.
So, now stimulation starts.
So there's now electricity
passing through Leila's brain.
Can you feel anything? No, nothing.
There's no smoke. I can't see any.
And during this stimulation,
Leila will move her fingers and do
the implicit learning paradigm.
Then we will measure simultaneously
how quick she can respond to
the visual target during this time.
What we expect to see is with motor
cortex depolarisation
that's more excitable
and then her reaction time
will improve.
And then we'll see
an increase in speed that she's not
constantly picking up a pattern, but
subconsciously,
she's getting better at learning.
The longer the stimulation lasts,
the greater its effects will be.
In previous experiments lasting 24
hours, permanent improvements
to the brain were forged.
We know from other research,
basic animal research, that
new connections between
individual nerve cells will be built
after about 30 minutes.
And after about a day,
they start to become functional.
So it's really changing the structure
of the brain by doing this? Yes.
It's not just a temporary effect?
Yes, so we have structural
alterations which allow you to move
your fingers quicker in this case.
With measuring the reaction times,
we will see that you'll probably
speed up in the range of 10% or so.
10%, and that's significant, is it?
10%, you wouldn't expect that?
Not without stimulation. Right.
The idea of being able to enhance
our intelligence, if you don't mind
having your brain stimulated, hints
at the dawn of a brave new world.
But if you're going to involve
computers, then why stop there?
Some scientists think the creation
of artificial intelligence
could transport us to new levels
of interaction and understanding.
It's something that has occupied the
minds of technology researchers
for decades,
and Horizon has featured
some of their wilder predictions.
Our descendant will not
be the child of the loin,
but the child of the brains,
the thing we call the computer,
which does not have to pass
through the birth canal.
And does not grow by a tablespoonful
of grey matter every 100,000 years,
which is the case in the rapid growth
of our brain,
but grows a factor
of 10 in power every seven years.
The computer generation.
There's no question that it'll match
us in narrow reasoning power by 1990,
and go beyond us to become the great
new intelligent race of the future.
The artificial intelligences of
the future will be worried about
weighty problems that we
simply can't understand.
And they may condescend
to talk to us. They may...
amuse us on occasion, or play
games that we like to play.
And in some sense,
they might keep us as pets.
Although those predictions haven't
been borne out, work on artificial
intelligence has continued to race
towards the goal of a man-made
super-intelligence, leading one
man to predict that a computer will
equal a human brain's power by 2029.
His name is Ray Kurzweil,
inventor and visionary.
He believes that our
understanding of the human brain
will soon be complete.
25 years from now, we will
have actually mastered
human intelligence.
We'll have both the hardware
and the software to recreate
human intelligence in a machine.
Kurzweil was one of the first to
make a computer that could read.
MACHINE: 'For score and seven years
ago, our fathers brought forth
upon this...'
If his latest prediction is right,
then we will understand
the human brain
at almost exactly the same time
as computers equal its power.
It's this culmination of events
that would lead to the singularity.
There's really a point in human
history where human society will be
profoundly transformed by creating
non-biological intelligence.
Machines that are ultimately
billions of times more capable
than human beings today.
And we will integrate with
this technology, and it will enhance
human potential.
We'll have to wait until 2029
to find out whether Kurzweil's
prediction is correct.
Until then, science can only
continue in its quest to fully
fathom our unique mental abilities.
Understanding what makes my
intelligence different from
that of someone like Einstein's
could be a question of my genes,
or the way I was brought up.
Maybe I'm just intelligent
in a different kind of way?
He was pretty good at physics.
I'm pretty good at...
Well, anyway,
2029 is not so far away
so maybe we'll just have to wait
and see who's so clever then.