All language subtitles for BBC.The.Code.3of3.Prediction.PDTV.XviD.MP3.MVGroup.org.eng

For as long as human beings
have walked upon earth,

we've tried to make sense
of our world

and predict
what the future will bring.

Yet today,

our lives seem more complicated
and unpredictable than ever.

And half the population
of the planet

now live in busy, sprawling cities.

Every day throws up
thousands of different encounters.

A mass of interactions and forces
that seem beyond our control.

WOMAN LAUGHS

It's hard to see how
any of this could be connected.

BABY CRIES

Yet when we start to look
closely at all this complexity,

surprising patterns begin to emerge.

It's these patterns that I believe
point to an underlying Code

at the very heart of existence

that controls not only our world
and everything in it, but even us.

As a mathematician,
I'm fascinated by the patterns
we see all around us.

Patterns that reflect the hidden
connections between everything.

From the movement
of rush hour crowds...

..to the shifting shape
of a flock of starlings.

The cacophony
of a billion Internet searches...

and the vagaries of the weather.

THUNDER ROLLS

CHEERING

Together, these patterns
and connections make up the Code.

A model of our world that describes
not only how it works,

but can also predict
what our future holds.

Around 500 years ago, a ship
was caught in a terrible storm.

As rain lashed the decks

and gale force winds tore
through the rigging,

the ship began to take on water.

The captain had no choice but to run
his ship aground and wait for help.

But help never arrived,
and the natives were hostile.

After eight long months, and with
his crew facing certain starvation,

the captain came up
with an ingenious plan.

He summoned the local chief
and told him his God was angry.

So angry, in fact,
that if they didn't bring supplies
within three days,

God would swallow the moon.

And sure enough,
as the moon rose on the third night,
it had already begun to disappear.

Terrified, the locals ran from
all directions towards the ship,

laden with provisions.

The year was 1504, and the captain?

Christopher Columbus.

And the reason he was apparently
able to command the heavens

was because he had
something like this.

It's a set of lunar tables.

And each one of these numbers
represents a lunar eclipse.

Today's date is June 15th, and it
says that in about five hours' time

the same thing is going to happen
to the moon here in Cyprus.

During a lunar eclipse, the earth
passes between the sun and the moon,

casting its shadow
across the lunar surface.

And there it goes.

The moon has been swallowed up
by the shadow of the Earth.

But the amazing thing is
actually the moon doesn't
completely disappear, cos...

there's a kind of...
red, ghostly moon up there.

And that's because
the light from the sun is being
refracted around the Earth.

Really quite spooky.

I can imagine how terrified
the islanders would have been
when they saw that 500 years ago.

And the only explanation for them
would have been that the gods
really were angry with them.

We now know that the movement of the
planets is incredibly predictable.

By understanding the Code,
we can model their orbits
far back into the past.

And see thousands of years
into the future.

It's thanks to the Code that we're
no longer frightened by an eclipse.

In fact, the Code
is such a powerful thing

that I'm even prepared
to entrust my life to it.

This strange contraption
is five and a half metres high.

Using the force of gravity,

a 30-kilogram ball will hurtle down
the ramp and fire off the end.

And when it does, I will be
sitting directly in its path.

If I get my sums wrong,
I'll be killed outright.

To calculate how far
the ball's going to go,

I need some
key measurements about the ramp.

Little h is 0.98 metres.

The angle is 49.1 degree.

So gravity, I know, on the Earth...

is 9.8 metres per second squared.

Interestingly, you don't have
to know the weight of the ball,
the mass of the ball.

That's not relevant to how far
the thing's going to go.

Two times gravity,
times the height, 5.5,

multiplied by the speed,
divided by 49.1,

take the cosine...

That will give me
a distance of 9.95 metres.

But we've got air resistance,
there's friction on the...
the ramp as well.

What about the wind today? 9.16.

OK, so the predicted distance
is going to be 5.6 metres.

That's where I think
the ball is going to land.

Which means if I set up my deckchair
here, I should be able to watch
the whole thing in complete safety.

OK, release the ball.

And that is the power of the Code.

We can do this again
and again and again...

..and the numbers mean
the ball is going to land
in the same place each time.

If everything in the world
behaved according to equations
that give definite answers,

we'd be able to predict the future
with absolute certainty.

But unfortunately
things aren't quite that simple.

The natural world often
appears so complex

it's hard to imagine we could
write equations to describe it.

Even though we might glimpse
what we think are patterns,

they seem
almost impossible to understand.

I've come to witness
a mysterious phenomenon

that happens here in Denmark
for a few short weeks every year.

WINGS FLUTTER

BIRDS TWITTER

WINGS FLUTTER

First few appearing, I think.

These are starlings,

making their annual migration
between southern Europe
and Scandinavia.

A single flock
can contain a million birds or more.

Their dance obscures the fading
evening light,

giving the formation
its eerie name -

The Black Sun.

There's another
massive group coming in.

Oh!

There are
thousands of them up there.

It's not really clear why
they do this.

It's maybe like, kind of,
safety in numbers.

The whole shape
looks quite intimidating.

It looks like
one large, black beast,

frightening off any predators

that might be looking
for a bit of dinner before sunset.

Look at that.

Ah.

It's almost hypnotic.

It's amazing.
There are so many of them,

it's a wonder they don't
smash into each other

and sort of knock some out of
the sky. But they don't seem to.

Incredible synchronisation.

Oh!

You're never quite sure
what it's going to do next.

'It's an almost
impossible achievement.

'How can each bird predict the
movements of thousands of others?'

That's extraordinary?

As strange as it seems, by reducing
each starling to numbers,

we can model what's happening
on a computer.

We start with a flock
of virtual starlings,

all flying at different speeds
and in different directions.

And then
we give them some simple rules.

The first is for each bird
to fly at the same speed.

The second rule
is to stay close to your neighbours.

And finally, if you see a predator
nearby, get out of the way.

Three simple rules are all it takes
to create something

that looks uncannily
like the movement of
a real flock of starlings.

Oh, here they come.

Oh!

HE LAUGHS

In fact, a recent study has shown

that even in a flock of hundreds
of thousands of birds,

each starling only has to keep track
of its seven nearest neighbours.

And then...they've all gone.

The sky's clear again.

Who'd have thought that something
so extraordinarily complex

as a constantly shifting flock of
thousands of birds in flight

can have at its heart such
a simple and elegant Code?

WOMAN LAUGHS

CHILD LAUGHS

BABY CRIES

It seems inconceivable
that human beings

could ever be reduced to
a mathematical model like starlings.

CLOCK TICKS

But Iain Couzin studies
how animals behave in groups,

and his research has revealed
some surprising parallels.

How can you possibly begin
to understand something
like this huge mass of people?

Even when you look at the crowd
for a few seconds,

you realise there's so many
complicated factors at play.

I started my research
looking at simple organisms,

organisms like ant swarms,
schooling fish.

And remarkably, our insights
from studying those systems

led to new insights
in studying human crowds.

But people are much more complicated
than a...a fish or an ant.

Exactly, but that's almost
the beauty of this,

is we're thinking
about more interesting things

when we're walking through crowds
than, "How do I avoid that person
and that obstacle?"

You know, we're thinking about
what we're going to cook for dinner
or what our friends are doing.

And so, in actual fact,
we're almost on auto-pilot,

and we're actually using
very simple rules of interaction

just like the schooling fish
and the swarming ants.

So can we learn things
from the ants?

We could learn an huge amount
from the ants.

Ants don't suffer
from problems such as congestion.

Because they're not selfish.
And I'm afraid to say we are.

We want to minimise
our own travel time,

but we don't necessarily care
whether we do so at the expense
of other individuals.

Of all the animals Iain has studied,

human beings are, in some ways,
the most predictable.

We walk at an optimum speed
of 1.3 metres per second,

and prefer to walk in straight lines
to get to our destination.

What happens
is you will naturally fall

into the slipstream of someone
moving in the same direction as you.

And so without you even knowing it,
you're forming a lane.

Similarly, pedestrians moving in the
other direction will also form lanes,

very much like the ants do.

These lanes help us
to avoid collisions.

However, in a large open space,

like the concourse
at Grand Central Station,

the lanes inevitably
cross each other,

which could lead to congestion.

But when you put an obstacle -
like this information desk -

in the middle of the crowd,
rather than getting in the way,

it acts like a roundabout

and increases the flow through
the station by as much as 13%.

These rules are so effective
at predicting what we'll do,

they can even be used to
simulate crowds of people.

Each individual is actually
described by a set of numbers

as they move through an environment.

Exactly. We're capturing the average
type of behaviour of pedestrians.

We're capturing these
simple and local rules that people
use within crowds

to then make predictions
as to how the whole crowd

is going to flow through
different environments.

We can use this underlying
Code of the crowd

to design buildings
that are more efficient and safer.

Simulations like these
are able to accurately predict

how quickly a building
can be evacuated,

even before it has been built.

As a crowd,
people are incredibly predictable.

There are simple rules that we
follow without being aware of it.

But most of the time,
we don't live on autopilot.

And when the crowd disperses, so too
do the rules of group behaviour.

SIREN BLARES

As individuals with our own free
will, we're much harder to predict.

Or so we think.

Before we gets started,
I would like to mention the rules.

They are very simple.

There are three throws
and there are only three throws.

We use a three-prime shoot,
which means you go one, two, three

and you release your throw on four.

A throw of rock is a closed fist.

You can throw it any way you want
as long as it is a closed fist.

Your paper must be horizontal.

Your scissors must be vertical.

That will be foul.

The game of rock, paper, scissors
is known all over the world.

And some people
take it very seriously.

For those of you who don't know,
and there should be very few,

the throw of paper
covers the throw of rock.

The throw of scissors
cuts the throw of paper,

and the throw of rock
crushes the throw of scissors.

In Philadelphia,
the Rock, Paper, Scissors League

competes four times a week.

The people in this room
are fighting

to go to the world championship
in Las Vegas

and the chance to win 10,000.

Sweetji in the lead.
Rock versus scissors for Sweetji.

You're on the verge of elimination,
Drew Bag.

Third and final set,
winner moves on.

THE CROWD CHANTS AND CLAPS

Rock versus scissors.

And what a match,
to take us down to the final four.

The intriguing thing about this game
is that it should be impossible

to predict what
your opponent's going to do next.

In rock, paper, scissors,
they're all pretty much equivalent.

So each throw beats one
and loses to another,

so essentially
it's a game of even odds.

A bit like a flip of a coin.

But if the game is entirely random,

every player
would be evenly matched.

And yet some people win time
and time again.

It is match point, Sweetji.

B-Pac has no points here
in round number two.

He will need two straight throws.

Can he get through number one?

No. Sweetji!

So now our final match of the night.

Sweetji,
you're going to play dOGulas.

The more we play, the more we're
influenced by our past throws.

Begin.

And that creates patterns that
can be exploited to win the game.

Sweetji came fifth
in the league last year,

and this season
looks set to do even better.

dOGulas!

Rock crushes scissors.

Sweetji still has point...

Rock crushes scissors!

SHE SCREAMS

Sweetji, Philadelphia Rock, Paper,
Scissors City League Champion
here at the Raven Lounge.

Congratulations. Thank you.

So that was five consecutive wins.

What was the key to your success,
do you think? I try to read people.

Yeah, you do, yeah? Or at least try
to think what they're thinking.

You're looking for their patterns
then? Yeah, a little bit like...

Their patterns,
and they'll be trying to learn mine
and go against that.

Rock, paper, scissors reveals
a fundamental truth

about human nature.

We are so addicted to patterns

that we let them seep into
almost everything we do.

And these patterns are the key

to predicting many aspects
of our behaviour.

Even the darkest parts
of our nature.

SCREAMS

Deceased. Female, five foot two.

Complexion, dark. Eyes, brown.
Hair, brown.

When you see this much activity
in such a small geographic area

in such a tight time frame,

that's a warning bell
that something's going on,

we have a predator operating.

Kim Rossmo has 20 years'
experience as a Detective Inspector.

He specialises
in hunting down serial killers.

The victim's body was found
here in the corner

by a police officer that came in
shortly after the crime had occurred.

The prime crime scene would be...

But Rossmo is no ordinary cop,

because he's got a PhD

and uses mathematics to understand
the patterns criminals leave behind.

There's a logic in how
the offender hunted for the victim

and the location where
he committed the crime.

If we can decode that and if
we can understand that pattern,

we can use that information to help
us focus a criminal investigation.

The reason it's so hard to catch
serial killers is because there's
often no link to their crimes.

They kill random strangers

in locations they have
no obvious connection to.

It's very common in the investigation
of a serial murder case

to have hundreds, thousands,
even tens of thousands of suspects.

It's a needle-in-a-haystack problem.

Where do you start?

In 1888, the most notorious serial
killer of all, Jack the Ripper,

killed five women
in London's East End.

Since then, countless people
have tried to solve the mystery
of the Ripper's identity.

But Rossmo thinks he
could have tracked him down

without seeing a scrap of evidence.

Because he's worked out where
Jack the Ripper most likely lived.

Based only
on the location of the crimes.

Flower and Dean Street should have
been the epicentre of their search.

And all he used to do it
is an equation.

Inherently, we're all lazy,

and criminals just
as much as anyone else.

They want to accomplish
their goals close to home
rather than further away,

because it involves too much effort,
too much time, too much travel.

The first half of Rossmo's equation

models what's known as
the least-effort principle.

It means that the crime locations

are statistically more likely
the nearer they are
to where the offender lives.

If you have a choice of going to
the corner store for a loaf of bread

or one that's seven miles down the
road, you'll pick the corner store.

It seems a bit gruesome to apply
the same thing to a serial killer

as to going and buying
a loaf of bread or milk.

Well, actually, if we can get over
the horrible nature of these crimes

and recognise that these are
human beings like the rest of us,

we can,
because we understand ourselves,

maybe bet some understanding
of these individuals.

The second half of the equation

describes something
called the buffer zone.

Criminals avoid committing crimes
too close to home,

for fear of
drawing attention to themselves.

It's the interaction of these
two behaviours that allows Rossmo

to calculate the most probable
location of the criminal.

These individuals have to
not only obtain their target -

or capture a victim -

but avoid apprehension by the police
and identification by witnesses.

The technique,
known as geographic profiling,

is now used by police
all over the world.

Police are examining the possibility
that a small explosion

near a branch of Barclays Bank
in West London

was the work of an extortionist.

Police believe the demand

came from the blackmailer
known as Mardi Gra.

In the late '90s, Rossmo
was called in by Scotland Yard

to help catch
the notorious Mardi Gra bomber,

who for three years
waged a campaign of terror

against banks and supermarkets.

A 17-year-old man is recovering
in hospital after being injured

in an explosion at a Sainsbury's
store in South London.

'Police are advising
the public to be vigilant.

'In truth, they can only wait
to see what Mardi Gra does next.'

How many bombs did he
let off during that time?

Total, 36 known linked offences.

So you can see, they range
from the north of Cambridge,

all the way down
to the strait of Dover.

But most of them
are in Greater London.

So this is a map showing
the locations of all the bombs
that were set off?

That's right. There's certainly
a concentration on London,

but it looks
pretty randomly scattered.

So now you're feeding those
locations into the equation?

Right. And what we have here now
is the geo-profile.

And that's going to show us
the most likely location

where the offender lived.

With dark orange being the most
likely or the most probable.

So we can see that the major
focus is around the Chiswick area.

In fact, in the report
we prepared for Scotland Yard,

we even prioritised
postcodes for that.

And how successful
was it in this case?

Well, let me show you
the locations...

of the two brothers,
Edgar and Ronald Pearce.

Right, that is really in
the hot zone, isn't it? Yes.

Edgar's home is in the top 0.8%

of the area of the crimes
in Greater London.

So less than 1%.
That's extraordinary.

Edgar Pearce had demanded
£10,000 a day from Barclays.

And when he and his brother
tried to collect it
from a cash point in Chiswick,

the police were waiting.

Two bothers in their 60s were
remanded in custody by magistrates

in connection with
the so-called Mardi Gra bombings.

Ronald and Edgar Pearce,
both from Chiswick in West London,

each face three conspiracy charges.

Based on the apparently
random location of 36 bombs,

Rossmo's geographic profile narrowed
the location of the Mardi Gra bomber

from 300 square miles
to a postcode in Chiswick.

Although his bother, Ronald,
was acquitted,

Edgar Pearce pleaded guilty
and was jailed for 21 years.

So do you think the bomber was aware
that he was creating these patterns?

No, he wasn't.
But it's very difficult for humans

to engage in
completely random behaviour.

Very few of us are aware of
the patterns we leave behind.

WOMAN LAUGHS

From the way we move in a crowd...

..to the choices we make
in a game...

Paper covers rock!

The victim's body was found here...

..or even how we commit murder.

In reality,
these crimes are not random...

None of it is random.

It's all part of the Code.

There are always
tell-tale patterns.

And if we're able to decode them,

we can use those patterns
to model our behaviour.

And this leads
to the intriguing possibility

that if we can reduce human beings
to numbers, we might
be able to predict our future

in the same way as we can predict
the movement of the planets
or the trajectory of a ball.

But the course of our lives never
seems to run entirely smoothly,

and the future rarely turns out
exactly as we'd planned.

I may have a good idea
what I'm going to be doing tomorrow,
or even next week,

but as the weeks turn into months
and months to years,
our future becomes less certain.

Every decision we make,
every situation we encounter,

every person we meet, sends
our life down a different path.

As you watch each stick floating
off downstream, there's no sure way
of predicting their fate.

I might be able to hazard
a guess where a stick
will be in two minutes.

But what about two hours? Two days?

'..Turn into years, our future
becomes far less certain.'

Life sometimes seems
so unpredictable
that we think of it as being random.

But in fact it isn't random at all.

Simply a sequence
of cause and effect.

A freak accident.

I'm so sorry.

A slight delay.

A missed bus.

A broken promise.

There are millions of factors
that intervene to affect
our journey through life,

and the tiniest shift
in any one of these can completely
change its future course.

The white one's caught in a dam,
but the red one's fast.

I think this'd be
a good finishing line.

And here comes the white.
It's way ahead of the red.

And white's the winner.

Right, let's give it another go.

The truth is,
our lives are controlled
by the strangest code of all...

the code of chaos.

Our lives aren't random,
they're chaotic,

a tangled web of cause and effect
in which insignificant moments

can escalate into events
that change our lives forever.

Any difference, no matter how small,
can have a huge effect
on the outcome.

It's this incredible sensitivity
to even the slightest change

which is one
of the defining features of chaos.

Because chaotic systems
appear so random, it's often
difficult to see a pattern.

And that has led us to sometimes
misinterpret our world
in a spectacular manner.

'In this land of many mysteries,
it's a strange fact

'that large legends seem to collect
around the smallest creatures.

'One of these is a mousy little
rodent called the lemming.

'Here's an actual living legend,
for it's said of this tiny animal

''that it commits mass suicide
by rushing into the sea in droves.

This film from 1958

set out to explain
the wildly fluctuating population

of these tiny rodents.

'Ahead lies the Arctic shore,
and beyond, the sea. And still
the little animals surge forward.

'Their frenzy takes them
tumbling down the terraced cliffs,

'creating tiny avalanches
of sliding soil and rocks.'

The legend of suicidal lemmings

was the accepted explanation
for why the Arctic can be overrun
with them one year

and completely empty the next.

'They reach the final precipice.

'This is the last
chance to turn back.

'Yet over they go, casting
themselves bodily out into space.'

This film popularised the belief
that lemmings are stupid,
reckless and suicidal.

The very word "lemming"
has come to mean as much.

The trouble is,
though, it isn't true.

In fact, it's been claimed
that the whole thing was faked.

The film-makers apparently flew in
hundreds of captive-bred lemmings

and drove them over the cliffs
and out to sea.

'Soon the Arctic Sea is dotted
with tiny bobbing bodies.

'And so is acted out
the legend of mass suicide.'

Now, as appalling as this sounds,
the reason for the alleged lemming
abuse stems not so much

from ignoring the moral code,

but rather an ignorance
of the mathematical one.

What no-one knew at the time
was that the incredible fluctuation

in lemming numbers has nothing
to do with mass suicide.

It's all because of chaos.

And there's a simple equation
at its heart.

So, if I want to know how many
lemmings there'll be next year,

what I need to do is take
this year's population, "P",

and multiply that
by the growth rate "R".

But not all lemmings will survive,

so there's a bit of the equation
which tells me how many lemmings
will die during the year.

So that's R times P times P.

So we can rewrite this equation

as the growth rate R times P
times one minus P.

Now, this equation isn't specific
to lemmings,

it actually applies
to any animal population.

And the interesting part
of the equation
is this number R, the growth rate.

Because when we choose
different values for R,

we get a very different behaviour
for the population growth.

The growth rate determines how
quickly a population expands.

For most species of mammal,
this is usually below 2.

With a growth rate in this range,
the equation predicts

that a population will rise until
it stabilises at a fixed value.

But it turns out lemmings
are one of the fastest-reproducing
mammals on the planet.

Let's take R equals 3.1.

The lemmings
don't stabilise now, but ping-pong
between two different values.

So the population is high, then low,
and back to high again, low again.

But when the growth rate reaches
a value just over 3.57

then something incredibly
unexpected happens.

Rather than levelling off
at a fixed number,

or fluctuating between two values,
their population erupts into chaos.

A plague of almost biblical
proportions one year can plummet
to near extinction the next.

It's almost impossible
to predict how many lemmings
you're going to have.

In fact, there doesn't seem to be
any pattern to this at all.

And of course, this is exactly
what's seen in reality.

Unpredictable
boom-and-bust lemming populations.

Lemmings are one of the few
creatures on Earth
that breed so quickly

their growth rate can sometimes
exceed this tipping point.

It's such an odd phenomenon
that mass suicide
seems like a plausible answer.

But the real explanation
comes from the Code.

From this equation.

The problem is we can never know
exactly how many lemmings
are born or how many die.

And just the smallest difference
in the growth rate R, produces
a totally different answer.

And this is true
of all equations that model chaos.

Although they can explain how
something happens,

they're almost useless
at predicting the future.

I can use an equation to calculate
where this ball will land,

because even if I'm slightly out
in any of my measurements,

it will only make a small
difference to the final result.

The ball will be released
from the ramp at 49.1 degrees.

But if this ball behaved according
to the laws of chaos,

the tiniest shift in the
ball's position

or the angle of release could
dramatically alter its trajectory.

I'd have no idea whether it
would just simply fall harmlessly

off the end of the ramp.

Or be sent into orbit.

I'd have no idea
where to put my deckchair.

It turns out
that much of the world is chaotic,

making it almost impossible
to predict.

But that doesn't stop us trying.

Knowing whether the sun
is going to shine

or the heavens are going to open,
is a British obsession.

But trying to plan our lives
around the vagaries of the weather

seems almost futile.

Even though we have precise
equations that can describe
how clashing air masses interact

to create clouds,
wind and rainfall,

it doesn't really help us
very much with our predictions.

THUNDER CRASHES

That's because
we can never know the exact speed
of every air particle.

The precise temperature
at every point in space,

or the pressure
across the whole planet.

And just a small variation
in any one of these

can produce
a vastly different forecast.

This is a map of how
the weather looks right now.

The blue lines represent
cold fronts and the red lines
represent warm fronts.

In order to make a prediction

what we do is to take
the mathematical equations
for the weather

and create a model.

Now the trouble is, I can't know
the precise atmospheric conditions,

so I take as much data as possible.

Then I make small variations in
the data and run the model again

and again and again and what I get
is different predictions according
to those slight variations.

So for the weather tomorrow,
the predictions are petty similar.

We've got a lot of blue lines
together predicting a cold front.

A lot of red lines together
predicting a warm front.

But look what happens when
I look a little bit further ahead.

So two days, three days ahead...

so you can see these
different predictions
are beginning to spread out.

You can still see some sort
of pattern in the weather

but if I move a week ahead...

..and I couldn't hazard a guess as
to what the weather's going to be.

There are red and blue lines
all over the place.

One prediction says it's going
to be hot, the other says cold,

and if I go ten days ahead,

it just looks like
a scrambled mess of spaghetti.

There's absolutely no way to make
any prediction that far in advance.

And that's why beyond just
a few days,

the weather forecast
can be so spectacularly wrong.

Once we understand
that the atmosphere is chaotic,

we can appreciate that the smallest
change in the initial conditions

can dramatically alter
what will happen.

The movement of just one molecule
of air can be magnified over time

to have a huge effect
on the weather as a whole.

We refer to this phenomenon
as the "butterfly effect".

The idea that something
as small as the flap
of a butterfly's wings

might create changes
in the atmosphere

that could ultimately
lead to a tornado
on the other side of the world.

CRASHING THUNDER

As a crowd, the patterns we make
are incredibly predictable.

Even as individuals our actions
are controlled by the Code.

And by untangling chaotic systems
like the weather,

we've uncovered evidence of the
Code in what we once thought of

as impossibly complex.

When we look at things
from a different angle,

surprising patterns emerge.

Patterns that can reveal
defining truths
about ourselves and our future.

In 1906, an unfortunate cow
laid down its life

for a place
in mathematical history.

One.

Ten.

264.

417.

'The cow was the subject
of a guess-the-weight competition
at a village fare.

'The lucky person who came closest

'would win the slaughtered
animal's meat.'

1,020.

2,137.

'The amazing thing
was nobody guessed correctly.'

..570.

'And yet everybody got it right.'

4,510.

To show you how they did it,

I'm not going to use a cow, I'm
going to use a jar of jelly beans.

450?

800?

12,000.

7,000.

How many jellybeans do
you think there are in this jar?

Um,

50...

80 thousand.

80 thousand?

No, actually 50,000.

50,000. OK, yeah.

It's incredibly difficult
for anyone to guess how
many jellybeans there are.

I asked 160 people
and most were way off the mark.

Everything from 400
right up to 50,000 beans.

In fact only four people
got anywhere near the correct
answer of 4,510.

Plus 1,500, plus 3,217, plus 83... .

If I add all the answers together
and take the average, I get the
combined guess of the entire group.

Plus, 4,000, plus 5,000,

463,

Plus 853, plus 1,000,

plus 5,000...

Which gives a grand total

of 722,383.5.

Somebody thought there
was half a bean in there.

Now there are 160 guesses made,
so let's see how close
they are collectively.

Wow, that's extraordinary.

You remember there were 4,510.

The average guess
to the nearest bean is 4,515.

I thought it would be close, but I
didn't think it would be THAT close.

That is ridiculous.

Though we had guesses that were
all over the place, up in 30,000s
right down in the 400s,

collectively we get something
which is just 0.1% away

from the real number
of beans in there.

So as individuals the guesses
are just that, guesses.

But when you take them collectively
they become something else entirely.

5,000. 1,450. 9,200.

What tends to happen
is that more or less as many people

will underestimate the number
of jellybeans as overestimate it.

1,763... 6,000.

A few people will be
way off the mark either way,
but that doesn't matter.

Provided you ask enough people,
the errors should
cancel each other out.

1,000. 1,275. 700?

The accuracy of the group is far
greater than the individual.

We call it
"the wisdom of the crowd".

160 people is a powerful tool
for working out how many jellybeans
there are in the jar.

But imagine what you could do
with a crowd of millions.

That's exactly
what they use here at Google.

With access to over two billion web
searches a day,

Google have found a way of tapping
into the wisdom
of the biggest crowd on Earth.

And by doing so,

they've been able to reveal
the forces that control our lives,

and harness them
to make predictions about us.

'Think of the things that people
search for on a daily basis.

'Think of the things that YOU
search for on a daily basis.'

I searched for cities in Mexico
and films in Hackney today.

Lots of people may be searching
for the similar...

a similar thing,
movies in Hackney, for example.

And if you look at that query
over the past three years,

um, what the pattern of searches
for that term looks like.

Google had a hunch
they could use all our searches

to make predictions about our lives.

They wanted to see
if they could match the pattern
of certain searches

with events in the real world.

Google began by seeing if they
could predict outbreaks of flu.

So flu has a nice seasonal pattern

and because it has that pattern
every year over many years,

we're able to...to take that trend

and say which search queries
match that pattern.

So we built a database
that included over 50 million
different search terms.

50 million?

Yes. Wow, yeah.

We didn't only include things
that may be related to flu.

We included things
like Britney Spears or...

Everything people search
for would be included.

When Google looked back over
the past five years of data,

there were certain search terms
whose popularity exactly matched

the pattern of flu cases.

So people were searching
for things like "symptoms"

or "medications"
or "sore throat".

There are other things
like complications.

So you're saying that
the sort of number of search
terms for flu-related things

almost exactly mirrors the actual
cases of flu that we see
in the population? That's true.

It is an indicator of flu activity
just based on lots of people
searching for these terms.

We were amazed by this finding.

As soon as they see this pattern
of search terms

Google can predict
there will be an outbreak of flu.

Often before people
had even gone to the doctor.

This is the extraordinary power
of the Code.

But it's just the tip
of the iceberg.

The searches we make
can be used to predict

where we'll go on holiday.

What model of car
we're going to buy.

Or how we're going to vote,

often before we know ourselves.

It's even been possible to forecast
the movement of the Stock Market

from the number of negative
words used on Twitter.

Analysing such vast amounts
of data, doesn't just allow us
to make predictions.

It can also tell us something
fundamental about ourselves.

You look out at a city like this
and it looks like, you know,
some arbitrary jumbled mess.

Yet the city IS people.

It's not the buildings
and the streets.

They're the stage upon which
the real actors

are playing out
the story of civilisation.

Geoffrey West is a physicist
who's spent his life trying to see
meaningful patterns in the universe.

And how he's turned
his attention to the dynamics
of human life in cities.

So you can see there's all kinds
of infrastructure here.

There's the obvious, the roads, the
electrical lines, the sewer lines.

They're an extraordinary network
that is sustaining New York City.

You know,
coming at it as a physicist,

I had this hunch that there is
an underlying code to all this.

West amassed data
about cities all over the world.

And the patterns he found mean that
for any given population size,

he can predict the amount of roads,

electrical wiring
or office space that city has.

But he also discovered something
much more surprising.

One of the most interesting results
we discovered was that, um...

Wages scale
in a very systematic way

and the rule that came out was that
if you doubled the size of the city,

you get this marvellous
15% increase in the wages.

If you live in a large city,
you're going to earn more? Yes.

So what, if there
are two mathematicians

in two different cities - one twice
the size - doing the same job,

one will have a bigger income?
On the average,
that is what the data say.

Was that a surprise to you
to see that? A huge surprise.

I thought there was
something wrong with the data.

And then it was like, "Of course!
That's why cities exist."

Incredibly, it's not just people's
salaries that increase.

When a city doubles in size,
every measure of social
and economic activity

goes up by 15% per person.

That's 15% more restaurants
to choose from.

15% more art galleries to visit.
15% more shops to go to.

In short, life gets 15% better.

You know it looks like
it's a magic formula

that we as social human beings
have discovered...

..this 15% bonus, so to speak,
is, I believe, the reason

that people
are attracted to cities

and why there has been
this continuous migration

from the countryside
and into the cities.

And at some deeper level,
actually drive our civilisation.

According to Geoffrey West,
humankind has an ultimate number.

It's this extra 15%

or 1.15.

He believes it's the most important
driving force in humanity.

This single number, 1.15,

predicts our future.

It will bring us together
in ever expanding cities

and shape our destiny for
as long as human beings exist.

Five hundred years ago,
when faced with an eclipse,

many of us would have believed it
was the work of an angry god.

But as we've unearthed
the language of the Code,

we've discovered that the apparent
mysteries of our world

can be understood
without invoking the supernatural.

And this for me
is what's so remarkable.

That despite the incredible
complexity of the world we live in,

it can all, ultimately,
be explained by numbers.

Just like the orbit of the planets,
life too follows a pattern.

And it can all be reduced
to cause and effect.

In the end,
even the flip of a coin

is determined by how fast
it's spinning

and how long it takes
to hit the ground.

The ultimate symbol of chance
isn't random at all.

It only appears that way.

When we don't understand the Code,

the only way we can make sense
of our world is to make up stories.

But the truth
is far more extraordinary.

Everything has mathematics
at its heart.

When everything is stripped away
all that remains is the Code.

Find clues to help you solve
the Code's treasure hunt at...

Plus get a free set of mathematical
puzzles and a treasure hunt clue

when you follow the links
to the Open University.

Or call 0845 366 8026.

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