Nova (1974–…): Season 32, Episode 17 - Newton's Dark Secrets - full transcript

When an Englishman buys many of Sir Isaac Newton's journals, he spends years decoding them and discovers a secretive side to the great genius. Apart from inventing calculus, outlining the laws of gravity, writing treatises on optics and the properties of color, and other brilliant scientific discoveries, Newton also practiced alchemy and was a disbeliever in the divinity of Christ (a criminal offense in his time.) He also proved to be a secretive man, who kept many of his thoughts to himself for many years, possibly afraid of the criticism he couldn't abide.

Are you wondering how healthy the food you are eating is? Check it -
In 1936, a huge collection

of scientific documents
and personal papers

was put up for auction
at Sotheby's in London.

World's greatest scientist,
Sir Isaac Newton,

a veritable treasure trove
of knowledge.

Shall we say starting...

These papers had never been seen
by the public,

and a large number of them
were bought

by the famous British economist
John Maynard Keynes.

Going... gone.

Many were written
in secret code,

and for six years, Keynes
struggled to decipher them.

He hoped they would reveal
the private thoughts

of the man who invented a new
branch of math called calculus,

figured out
the composition of light,

and gave us the laws of gravity
and motion

which govern the universe...

The man who is considered
the founder of modern science,

Sir Isaac Newton.

Newton ushered in an age,

the Newtonian age,
and it was premised

on the concept that everything,
virtually, in the universe

was amenable
to scientific understanding.

Newton's work has a beauty
and a simplicity and an elegance

that makes it the greatest work
of science ever done.

But what Keynes found shattered
his image of Isaac Newton,

for in these manuscripts Keynes
discovered an Isaac Newton

unknown to the rest
of the world...

An Isaac Newton who seemed
obsessed with religion

and devoted to the occult.

He is known today

as a sort of a high priest
of the Age of Reason,

but this is
a misconstruction of Newton.

The modern interpretation
of Newton

is about as far
as could possibly be

from what Newton himself

On the one hand we can recognize
him as a scientist,

but on the other hand,
he's pursuing

an activity which we now label
as a pseudoscience.

Now scientists and historians
are trying to reconcile

the Isaac Newton
they thought they knew

with the Isaac Newton

they're discovering
in his private papers.

Our project now must be to see
Newton the way that Newton was

rather than trying to see Newton
the way we want him to be.

What are these mysterious
documents revealing

about one of the greatest
scientists ever?

"Newton's Dark Secrets,"
right now on NOVA.

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In a library in Jerusalem lies
an intensely curious document.

It was written
about 300 years ago,

and only a handful of scholars
have ever examined it.

The author was arguably

the most important scientist
of all time,

a genius who uncovered
the laws of physics

that govern the entire cosmos,
Sir Isaac Newton.

The subject:
Newton's calculation

of the date the Bible said the
world as we know it would end

in the battle of Armageddon,
the year 2060.

If this calculation
were correct,

then we are close to the...
the time of the end.

That's exactly what this sort
of calculation would point to.

When this document came
to public attention recently,

it was headline news.

But why was Isaac Newton making
this dire prediction?

We find it surprising

that Newton sounds
like a televangelist

talking about the end of time.

We only find it shocking

because we've made Newton
something that he's not.

We've made Newton

in a rationalist,
enlightened image.

That's just not Newton.

What these manuscripts reveal

is a very different Newton
than most people conceive of.

This is a Newton who is not
a cold, calculating scientist.

This is revealing Newton
in all his glory,

warts and all, if you will.

So, who was
the real Isaac Newton?

On a small farm in rural England
called Woolsthorpe,

the conflicted life
of Isaac Newton began in 1642.

That same year,
the astronomer Galileo had died,

and his work was still sending
shock waves through Europe.

Galileo had risked his freedom
by challenging

the ancient belief
held by the Catholic church

that the sun moved
around the earth.

Based not on faith
but observation,

he confirmed the earth was
just one of several planets

orbiting the sun.

It was the dawn of
the Scientific Revolution,

an age when science and reason
would redefine the world.

There was a sense
of a whole new era.

The very idea

of having the empirical world
answer our questions...

That idea was taking hold

in a way that had almost
never done so before.

And from a young age, Newton
was gripped by this new outlook.

As a boy, he pored over a book

called The Mysteries
of Nature and Art,

a manual for building
mechanical contraptions

and investigating
the natural world.

He was preoccupied

by the things that preoccupy
physicists, by time and motion,

so he made windmills,
he made little boats,

he flew kites that supposedly
"affrighted" the locals.

He tied candles to them
and they were put up,

and they thought
that they were comets.

But from the start, there was
another side of Isaac Newton.

His father died
before he was born,

and when he was
just three years old,

his mother remarried
and moved away,

leaving young Isaac behind
with his grandparents.

Newton later confessed
to such rage that he wanted

to burn his mother and
stepfather in their house.

And by the time he left home
for Cambridge University,

Newton had lived
through two decades

of violent political
and social turmoil...

a bloody civil war,
the beheading of the king

and the restoration
of the monarchy

under Charles II in 1660.

At Cambridge, Newton buried
himself in his studies.

Truth... is the offspring
of silence

and unbroken meditation.

He didn't go anywhere.

I mean, he rarely traveled.

He never went to the Continent.

He was that insular...
I mean, he stayed in his rooms,

he worked seven days a week,
18 hours a day,

and he pushed himself,
drove himself.

He had a library of his own

that had about 1,600
or 1,800 volumes,

but it was very much
a world that came to him

through printed matter or
through manuscripts from others.

The decadent atmosphere
of Cambridge

was something the reclusive
young Newton wanted no part of.

It was a time...

particularly after
the restoration of Charles II,

by many of the antics
of his fellow students...

Drinking, going
after bad young women

in local villages.

To resist temptation,
Newton drew up a plan

that he'd stick to
for the rest of his life.

The way to chastity

is not to struggle directly
with incontinent thoughts

but to avert ye thoughts
by some employment,

or by reading, or meditating
on other things, or by converse.

For he that's always thinking
of chastity

will be always thinking
of women.

He's a very silent,

thoughtful young man
who, I suppose, looks

as though he's utterly tedious
from the outside.

There's no evidence, I think,
that anyone liked him at all,

apart from his friend
John Wickins.

John Wickins was
another Cambridge student.

He and Newton became roommates
after both grew unhappy

living with students
who put pleasure before work.

They have a very
peculiar relationship,

because Wickins is somebody

who is of a higher status
than Newton at Trinity

and seems to have become
Newton's amanuensis,

i.e., his secretary,
over the following 20 years.

But they must have been
very close...

They lived in the same rooms
for 20 years.

As a student, Newton devoured
the latest scientific ideas.

It was widely accepted
by this time

that the planets orbit the sun.

But now the question was
how did the planets move?

What held them in their orbits?

The most popular theory came

from French philosopher
René Descartes,

who thought of the universe as
a giant machine, like a clock.

Descartes said everything...

Even the orbits of planets...
Could be explained simply

as the physical interactions
of parts of this machine.

But Newton had trouble
accepting this view of nature.

Newton's a very smart guy,
and he became convinced

that the only types
of statements

that are acceptable
are ones which you could,

to put it bluntly,
test in the laboratory.

But just as Newton was probing
the limits of Descartes,

the plague struck England.

Thousands died every week.

The university closed,

and Newton returned home
to avoid infection.

And it was here
in the apple orchard

just outside the family home

that the legend of Isaac Newton
was born.

The story, of course,

is that he's lying
in the garden there,

and instead of thinking
about girls,

he's thinking about the moon

and how it goes around the earth
and so on.

And he, uh... an apple falls...

and the story goes that bang,
he suddenly has the idea

that the same thing
that's making the apple fall

is what's holding the moon
in its orbit.

Newton told this tale himself
in his old age,

claiming that with the fall
of that apple,

he realized that what held
the planets in orbit

was not a physical mechanism
like Descartes's clockwork

but an invisible force
he called gravity.

And he was convinced

that the force pulling apples
down to earth

and keeping the moon in orbit
around the earth

were one and the same.

He stayed up late
in the evening,

calculating the strength
of that force

by the light of the fire.

But when the numbers
didn't quite work out,

he put the idea aside...
or so the fable goes.

I doubt that an apple was what
stimulated him to get the idea.

It's almost certainly
an apocryphal story.


I don't think it's even known
whether it ever happened.

I'm extremely skeptical

about the role of fruit
in Newton's life.

But there is no doubt
that the motion of objects

like apples and the moon
captivated Newton at this time.

The Italian scientist Galileo
had proved

in a famous experiment on motion

that all objects falling
to earth pick up speed,

or accelerate downwards,
at the same rate,

regardless of their mass.

And finding the average speed
of a falling object

was a straightforward process.

For example, if you want to find

the average speed
of an apple falling from a tree,

all you have to do is divide
the distance the apple travels

by the time
it takes the apple to fall.

But Newton was not satisfied
with the average.

What would be the speed
of an apple

which is constantly accelerating
at every point along the way?

What would the apple's velocity
be halfway to the ground?

To find out, you can measure
the apple's average speed

over smaller and smaller periods
of time.

The shorter the time interval,
the closer you get to knowing

the apple's speed
at that moment.

But to find its precise speed
at a single instant,

you have to reduce
that time interval

as close to zero as you can.

Newton invented a way
to make that time interval

infinitesimally small.

What is "infinitesimally small"?

That is smaller than any number
that you can think of.

It's not zero, but it is smaller

than any number
that you can think of.

For the first time,
it was possible

to calculate quantities
that are constantly changing,

like the speed of a falling
apple at any particular moment

or how a planet's position
changes over time.

With this technique,
Newton invented

an entirely new branch of math
called calculus.

And that changed
all of science, of course.

The whole way of looking
at the world changed

because of calculus, yes.

Calculus was
a quantitative understanding

of the way things change...

Not just velocity,

but in physics, in chemistry,
even in populations,

how fast is a population
changing over time.

This mathematical
framework becomes

the language in which
modern science is formulated.

Today, calculus
shows up everywhere

from analyzing the stock market

to modeling global
climate change.

By the time he was
22 years of age,

working on the calculus
at Woolsthorpe,

he was the greatest

the world had ever seen,
and yet no one knew.

Only Newton knew,
and it was his secret.

This was a guy who adored
computation of every kind.

Among the things
that you can see,

if you open his manuscripts,
for instance,

is there are places
where you'll find

he's calculated logarithms
out to 50 places

and things like that,

not because he needed it,
but because he liked doing it.

I mean, it was a pleasure to him
to do that sort of thing.

And if that weren't enough,

Newton overturned
accepted wisdom

about how colors are produced,

performing an experiment
on himself

with a large needle, or bodkin.

I took a bodkin and put it
between my eye and the bone

as near to the back side
of my eye as I could...

and pressing my eye
with the end of it,

so as to make
the curvature in my eye,

there appeared several white,
dark and colored circles.

Fortunately, Newton
found a safer way

to investigate light and color,
using a prism.

From Aristotle to Descartes,

scientists thought sunlight...
Or white light... was pure.

Colors were produced

by physically modifying
white light,

which they believed
passing it through a prism did.

But Newton decided
to see for himself.

Sending sunlight
through a prism,

he produced
the spectrum of colors.

And then he went
one step further.

He sent the red ray of light
through a second prism.

Instead of making a new color,
it remained red.

Newton concluded
that white light is not pure...

but a combination of all
the colors of the rainbow.

He thought of the prism
actually as a separator

of the objects that are
all in the original light.

This was very hard for
almost everybody to swallow,

because it meant that when
you're looking at white light,

you're looking at something

which has all the colors
already in it.

This seemed completely
counterintuitive, and indeed,

frankly it's counterintuitive
to most people today.

Only 25 years old,

Newton had made some of the most
stunning breakthroughs

in the history of science.

But he kept them
almost entirely to himself,

just as he had done
with calculus.

After the plague subsided,
he returned to Cambridge,

where he worked his way up
to an appointment

as the Lucasian
Professor of Mathematics,

the position held
by Stephen Hawking today.

Newton became known
for his prematurely white hair

and for his long-winded lectures
on light.

That belongs to refractions,

possibly founding
their demonstration

on a certain physical hypothesis

not well established,

I judge it will
not be unacceptable

if I bring
the principles of science

to more strict examination...

The introverted Newton had
little time for students,

and they had little interest
in him.

Years later,

one of Newton's laboratory
assistants would recall...

So few went to him,
and fewer that understood him,

that oftentimes he did, in
a manner, for want of Hearers,

read to the walls.

But Newton's study of light
was about to start a revolution.

50 years earlier,
Galileo had built

one of the first telescopes.

It used glass lenses to gather
light from distant objects

and focus it for the observer.

But this kind of telescope
had a problem.

Its lenses produced
fringes of color

around the edges of the objects
being observed.

And that meant that the objects
that you looked at

always had this
chromatic aberration:

They always looked colored, even
when the original object wasn't.

And Newton began on the side

to make some things with his
own hands, and he designed

a remarkably and radically
different kind of telescope

from anything
that had been built before.

Newton realized that the edges
of a lens behave like a prism,

breaking white light
into different colors

as it passes through.

So he abandoned lenses
and substituted a mirror

to gather and focus light
from distant objects.

And because the light
never passed through a lens,

it was free of color distortion.

Newton's telescope was
only six inches long,

but Newton bragged
that it could...

Magnify about 40 times
in diameter,

which is more
than any six-foot tube can do.

I have seen with it Jupiter,
distinctly round,

and his satellites.

It was an instrument

that has left its impact
on astronomy ever since.

Our huge telescopes of today
are built on this model.

They're gigantic versions
of this tiny little thing.

These are the telescopes

that sit on the top
of the great mountain peaks.

These are the telescopes
that we launch into space

to peer into the deepest parts
of the visible universe.

Newton regarded his invention
as just a toy,

but a colleague took it
to London,

where it was shown off
to King Charles II.

The effect that it had
on Newton's contemporaries

was immediate and dramatic.

It brought Newton
onto the world stage of science,

and Newton became
an overnight sensation.

Newton was elected a member
of the Royal Society,

a group of leading scientists
in London.

Most of them were awed
by the whiz kid from Cambridge,

and Newton was so delighted
that he promised to send

the Royal Society a paper
he had written on his discovery

that white light is made up
of different colors.

But members of the Royal Society
had no idea

that Newton was studying

something far more mysterious
than light by this time.

His private notebooks reveal

that the same year he became
a professor at Cambridge,

he bought two furnaces,
an assortment of chemicals

and a strange set of books.

Isaac Newton had become
an alchemist.

Alchemy is an ancient
and secret practice

with roots in the Middle East.

By carrying out lengthy and
complex chemical procedures,

alchemists tried to produce

a magical substance called
the philosopher's stone.

The philosopher's stone
was so potent

that even a small quantity
was said to perform miracles:

curing ailments,
conferring immortality

and transforming ordinary metals
like lead into pure gold.

In the 16th and 17th centuries,
there were many, many people

who came to courts in Europe
and claimed

that they possessed
the philosopher's stone,

and they were employed by nobles
and princes throughout Europe

to make gold.

In some instances, it was
immensely profitable.

You could milk a duke or prince

of a substantial amount
of money, no question.

But if you got caught,
it was extremely dangerous.

We know that one
of the customary punishments

for defrocked alchemists,
as it were,

was to be hanged
on a gilded scaffold,

and sometimes they were forced
to wear suits of tinsel

as they were hanged,
to make it a public spectacle.

As Newton immersed himself
in alchemy,

his paper on light was igniting
a firestorm in London.

The job of evaluating
Newton's ideas fell

to another Royal Society member,
Robert Hooke,

who would become
Newton's lifelong nemesis.

The paper got published, and
Hooke wrote a report on this,

and it's a peculiar report,
because effectively speaking

what it says is "I accept
all of Newton's experiments,

"but whatever is new in them,
I already did,

and all of his claims
about light are wrong."

For four years, Newton
and his critics fought it out,

with blow after blow published

in the magazine
of the Royal Society.

The sensitive Newton
was mortified.

Newton was allergic
to criticism...

I mean, really allergic.

He went off the wall
when people criticized him.

The problem for Newton was

having anybody question
what it was that he had done.

He didn't want to tell anybody
about it in the first place,

but if he was forced to do it,

you sure better believe
what he said.

He cannot convince
as many people as he wants

that what he said is true,
and that defeat,

if you like to call it that,
was very bitter for him,

and by the mid-1670s,
he's withdrawn completely

from the international world
of science.

Newton vowed
he would never publish

a scientific paper again.

In the isolation of Cambridge,

Newton threw himself
into alchemy.

Alchemy had been outlawed,
because the British government

feared that frauds would debase
the currency with fake gold.

And for years,
controversy has raged

over why Isaac Newton
took up alchemy.

Even Newton's lab assistant
was baffled.

What his aim might be, I was
not able to penetrate into,

but his pains, his diligence...

Yes, those times
made me think he aimed

at something far beyond the
reach of human art and industry.

In the past, many scholars
dismissed Newton's alchemy

as scientifically worthless...

but now they're taking
a second look.

To find out what Newton was
really up to, Bill Newman

has begun deciphering
Newton's coded recipes

and recreating alchemical
experiments Newton did

300 years ago.

If we want to figure out
what's going on

in these laboratory notebooks,
that's the way to do it...

Actually try the experiments
and see what happens.

Newton believed that
in the distant past,

people knew great truths
about nature and the universe.

This wisdom was lost over time,
but Newton thought it was hidden

in Greek myths,
which he interpreted

as encoded alchemical recipes.

In some instances,

he interprets the myths

in a very, very exact way,

so that they correspond
to actual recipes.

But getting these recipes right
is no easy matter.

Like all alchemists, Newton
concealed his ingredients

in bizarre-sounding terminology.

Our body, thus compounded,

is called a hermaphrodite...

being of two sexes,

and it is both father
and mother to the stone.

He used very colorful language

that's typical
of the alchemy of the time.

For example, he talks about "the
green lion," "the sordid whore"

and "the menstrual blood
of the sordid whore."

These are terms that had
very specific reference

in 17th-century alchemy.

One of Newton's recipes,
called "the net,"

comes from the writings
of the Roman poet Ovid.

In his poem "The Metamorphosis,"
Ovid tells the story

of the god Vulcan
catching his wife, Venus, in bed

with the god Mars.

According to the myth, Vulcan
made a fine metallic net

and hung the lovers
from the ceiling for all to see.

In alchemy,

Venus, Mars and Vulcan mean
copper, iron and fire.

Viewed this way, the myth
becomes an alchemical recipe.

And if Bill Newman has
interpreted the recipe correctly

he should get the same results
that Newton got 300 years ago:

a purple alloy known as
"the net," which was believed

to be one step towards
the philosopher's stone.

Behold, the net.

It worked.

A purple alloy with
a striated, netlike surface.

It worked perfectly.

By recreating these recipes,
Bill Newman is finding

that Newton's alchemy contained
key elements of modern science.

It was a systematic process

with results that could be
reproduced and verified.

And historians have
also discovered

that Newton was not alone
in pursuing alchemy.

Other scientists of the day,

including members of the Royal
Society, were alchemists, too.

Perhaps Newton's alchemy was
less an occult practice

than another way to investigate
the natural world.

Alchemy was really
matter theory.

Alchemy was a science which
pursued the most basic questions

of: What is the earth?

What is all of the universe
made up of?

What are the components
of matter?

There was a profound element
to the practice of alchemy

which really makes it deserving

of being called
early modern chemistry.

He's not a madman

playing around with strange
spiritous substances;

he's trying
to actually figure out

how to change
material particles around

to get one thing out
of something else.

And that's not so weird.

Newton's alchemy came
as a surprise

when it was discovered
in the papers bought

by the economist
John Maynard Keynes in 1936.

But other manuscripts
now housed in Jerusalem

contained an even
greater surprise.

For most of his life, Newton
held a dangerous secret.

As a fellow at Trinity College,
he was required

to become a minister
in the Church of England.

But this was something
he violently opposed.

Newton became convinced

that the central doctrine
of Christianity, the Trinity,

or the idea

that Father, Son and Holy Spirit
were all equally divine,

was not true.

The more ancient Christian texts
he read,

the more he believed
Christ was the son of God

but not God's equal.

That God is extremely powerful
and unique,

Newton, as the saying goes,
"reads himself into heresy."

In other words, Newton begins
to minimize, to play down,

eventually to deny
the divinity of Christ.

And Newton comes
to the conclusion very early on

that the Trinity is a blasphemy
on the First Commandment,

because the First
Commandment says

that "Thou shall have
no other gods before me,"

and the worship of the Father,
Son and Holy Ghost,

from Newton's point of view,
is a heresy.

But denying the Trinity
was illegal,

and Newton was
risking everything

by holding these beliefs.

If Newton had been exposed
while he was at Cambridge

as an anti-Trinitarian, his
career would have been over.

He would have been ostracized.

It's almost certain

that it wouldn't have involved
being put to death,

but definitely prison
would have been one possibility.

Newton was eventually excused
from becoming a minister,

but he wrote more
about theology and alchemy

than science and math combined.

Only recently made available
to the public

at the National Library
in Jerusalem,

these documents are now
revealing that for Newton,

religion and science
were inseparable...

Two parts of the same
lifelong quest

to understand the universe.

Newton himself wanted
to design a universe

in which God was absolutely
present and absolutely powerful.

There's an enormous irony there.

In the 18th century,
gangs of interpreters,

most of them French, will take
the God out of Newton's world.

It's a very common image
of what the Newtonian world was,

that it was soulless,
that it was mechanical,

that it really wasn't
theologically motivated at all.

Now, ironically,
that's very anti-Newtonian,

because Newton argued
that God had to be present;

you couldn't read him out
of the universe.

The most beautiful system
of the sun, planets and comets

could only proceed
from the counsel and dominion

of an intelligent
and powerful being.

Newton owned more
than 30 Bibles,

and he examined them
as rigorously

as he did the natural world.

Correlating Biblical passages
with astronomical information,

he redated ancient history,

drawing up elaborate charts
and chronologies

that show civilization starting
around 980 B.C.

I have hundreds and hundreds
of pages

of computations and workings
and reworkings

where he tries to probe this

over a period
of close to 30 years.

Time and time again
he'll come back to it,

calculating and recalculating,
trying to make it work,

just the way he tried to make
his theories of light work.

With the same fervor that
he brought to science and math,

Newton also combed the Bible
for keys to the future.

What he was trying to do
is determine

when the end would come,
when Christ would return,

when all the apocalyptic events
of the end times

would come to a head.

And that date is now alarmingly
close... the year 2060.

Newton is not a man
who keeps his theology

in a box that he brings out
only on Sundays

and then a man who does
his science as a working man

the rest of the week.

Newton sees his work
as a seamless unity,

and his project is to understand
the truth of God.

Most people today think
of religion and science

as completely different spheres.

In Newton's day, science,

the investigation of the natural
world, was a part of religion.

It was... all questions in some
ways ended in divine knowledge.

Alchemy and religion

might have continued
to dominate Newton's thoughts,

but in his early 40s,
he received a surprise visit

that would refocus him
on physics.

It was the astronomer
Edmond Halley,

now known for the comet
named after him.

He asked Newton
an esoteric-sounding question

about planetary orbits.

My question is this:

What kind of curve
would be described
by the planets,

supposing the force
of the attraction
toward the sun

to be reciprocal
to the square of
the distance from it?

An ellipse.

An ellipse... how do you know?

I've done the calculation.

You have?

How did you calculate it?

I'll show you.

Uh, should be here somewhere.

Oh, don't worry.

I will redo the calculations.

I'll send you a copy.

Halley's question would change
science forever.

Through years of observation,
scientists had discovered

that the planets move around
the sun not in perfect circles

but in slightly elongated,
elliptical orbits.

But no one could explain why.

Halley and many other scientists
had begun to suspect

that the planets were attracted
to the sun

by some kind of force.

They guessed

that this attraction became
weaker with distance

in a mathematical relationship
called the inverse-square law.

For example,
the inverse-square law says

that when a planet is twice
as far from the sun,

the gravitational attraction
it feels is four times weaker.

But no one had been able
to prove

this resulted
in elliptical orbits.

Several months later, Halley
received a paper from Newton.

It was Newton's
mathematical proof

that a planet obeying the
inverse-square law of gravity

must travel
in an elliptical orbit.

Newton may have used calculus
to arrive at this

but he had not published
this new form of math,

and his proof was written

in the traditional language
of Euclidian geometry.

But Newton wanted more
than a mathematical proof.

He wanted to know how
the planets move through space.

For the next 18 months,

Newton worked on this question
day and night.

He barely ate, he barely slept,
and he saw no one.

When you look at what he did
during that time,

it's difficult to believe

that any one human being carried
out this amount

of novel mathematical and...
mathematical physics research.

Finally, he submitted a 500-page
draft of his masterpiece,

the Principia Mathematica,

to the Royal Society
for publication.

It is the greatest book of
science ever written bar none.

It is the most magnificent work,

it is the most
all-encompassing work,

it is the most daring book

of any scientific treatise
ever written.

After the publication
of the Principia,

Newton... Newton is the man.

I mean, very few people
can understand

what this thing is about,
but a lot of people can see

there's something important
in here.

What people saw was that Newton
was providing a new framework

for understanding the universe,

building on centuries of work
by his predecessors.

Galileo had spent years
studying motion on earth

and determined that projectiles
always follow a curved path

called a parabola.

But Galileo believed that
motion of celestial objects,

like the moon,
was very different.

Galileo still believed
that there were differences

between the terrestrial
and the celestial.

He retained the idea...
That was ancient...

That motion was different
up at the moon and above.

Newton disagreed.

He thought the same laws
must govern motion on earth

and in the heavens.

To demonstrate this,

he would have to devise
a set of laws so powerful

they could explain
motion everywhere.

He began the Principia
with a set of ground rules...

His famous three laws of motion:

An object in motion will remain
in motion forever

unless acted on
by an external force;

an object's rate of acceleration
is proportional

to the force exerted on it;

and for every action, there is
an equal and opposite reaction.

These laws allow scientists to
make such accurate predictions

about how objects move
that they are still used today

to send rockets into space
and explore other worlds.

But explaining
the orbits of the planets

required another ingredient.

This brought Newton back

to the work he had begun
20 years earlier on gravity.

To show how gravity works
on earth and in the skies,

Newton designed
a thought experiment.

He imagined firing a cannon

from the top
of an extremely tall mountain.

From his first law of motion,

he knew the cannonball would
travel in a straight line

at a constant speed forever.

But gravity pulls
the ball downward.

If its speed is low,

the cannonball hits the earth
near the mountain.

The higher the speed, the
farther away the ball lands.

If you throw it faster,
it comes... farther away;

even faster, farther away.

Even faster, it may go
a thousand miles.

Even farther, it may actually go
almost halfway around the earth

and there hit the earth.

Newton imagined that
if its speed were high enough,

the cannonball would travel
all the way around the earth

and settle into orbit.

The orbit of the cannonball
around the earth

was a balancing act between
the cannonball's tendency

to fly off in a straight line,

and its being yanked back
towards the center of the earth

continuously by
the force of gravity.

So in Newton's picture of the
world, there were two things:

the natural tendency
of an object

to travel in a straight line,

which was true on earth
or in space or anywhere,

and there was
the attraction of gravity,

which was true
on the surface of the earth,

and it was true up in space.

Newton's breakthrough was

to see that the moon's orbit
around the earth

and a cannonball's motion
on earth

were governed
by the same law of gravity.

That is a beautiful way
of persuading you, me

and probably his colleagues

that cannonballs falling
to the earth

and the moon falling
to the earth

is one and the same law
of physics... gravity.

The moment that
he realized that,

almost everything else follows
from that.

Newton reasoned

that if gravity governed motion
on the earth and the moon,

why not on Jupiter
and its moons,

which he had seen
with his reflecting telescope?

Why not the entire solar system?

In a bold leap,
Newton proclaimed

that this invisible
force operates

everywhere in the universe.

It's an incredible leap.

It's beyond anything anybody
had imagined at the time.

Newton called it the
universal law of gravitation,

and he wrote it in one simple
mathematical equation.

It's so important
because it really tells us

how nature operates
in a fundamentally new way.

Newton is saying,

"The same thing that is going on
in the heavens

is going on on earth
and vice versa."

It gives us a guidebook to
answering the age-old question

of what causes the rise
and fall of the tides.

It gives us answers

to the orbits of the planets
and their positions.

It's a tremendous act
of intellectual triumph,

one of the great keystone,
cornerstone pieces

of our intellectual heritage.

It was a total revolution.

The universal law of gravity
was a complete revolution

in the way that we think about
the world, the solar system,

therefore the universe...

Whatever the size of
the universe was in those days...

And therefore the way
we think about ourselves.

The Principia showed a promise

that gravity by itself
could account

for virtually all the motions we
know of in our planetary system,

and the rest of science,
to this day,

has built off
of that foundation.

Newton turned out to be
more correct about that

than he could possibly
have been confident of.

But Newton was not able
to enjoy his success for long.

As soon as the Principia
was published,

Newton's old rival,
Robert Hooke, claimed

he has come up with some
of the key ideas first.

And later, others attacked it

because Newton did not explain
what gravity is,

just how to calculate
its strength.

Newton himself
didn't understand it.

How can this object
attract this object?

There is nothing
in between them.

That seemed to them

as going back to some sort
of an occult philosophy.

In fact, some think
Newton's idea of gravity

was related to the occult
practice of alchemy.

Newton was fascinated
by an alchemical process

called the
"vegetation of metals,"

in which inert metals
seem to come to life

and grow like plants.

Today, we know
this is just the reaction

of mercury and silver
with a solution of nitric acid.

But Newton thought
these kinds of reactions showed

that mysterious,
invisible forces

he called "active principles"

were at work everywhere
in nature.

Perhaps he thought of
the invisible force of gravity

in the same way.

Newton pursued alchemy

because it gave insight into
the active principles of nature.

Gravity was an occult force...
It didn't have an explanation...

And Newton believed
that it was possible

that gravity was
one of those forces,

one of those active principles.

And so in that sense,

Newton's alchemy
could give insight into gravity.

Yet by the early 1690s, after
more than 20 years of research,

Newton's alchemical experiments
had yielded

no scientific breakthroughs

like those he'd made
in math and physics.

We're not quite sure exactly
what he was trying to do.

He certainly was looking
for something,

and, you know, it's obviously
something quite big,

and he obviously
did not find it,

because he opted not
to publish anything about it.

I think there's no question
that he was disappointed,

because he was looking for
ultimate answers to questions

and he had failed in alchemy

as he had not failed
in any other pursuit.

Finally, Newton had what many
think was a nervous breakdown.

He made wild accusations
against his few friends

charging one,
the philosopher John Locke,

with trying
to "embroil" him with women.

Locke is puzzled
by the whole thing:

you know, "What's up
with Isaac there?"

He wasn't running
a brothel on the side

and bringing Sir Isaac to it.

When Newton explained
that he was sick

and had gone without sleep
for five nights,

his friends forgave him.

He was knackered.

If he had a breakdown,

I think it was probably
because of exhaustion.

Whatever the cause,
Newton's illness was brief.

Within a few months, he seemed
to have regained his composure.

And soon a strikingly different
Isaac Newton

began to take shape.

Newton moved to London and was
appointed Master of the Mint,

a well-paid job
that put him in charge

of issuing new currency and
cracking down on counterfeiters.

About two dozen counterfeiters
were executed

while Newton was in charge.

Newton became
a member of parliament,

president of the Royal Society
and was knighted.

He commissioned at least
14 portraits of himself.

It is an extraordinary change.

He's very much this icon

and he settles into that role,
I think, in London,

and likes the... the role
of the great man.

A year after Robert Hooke died,

Newton published his second
great masterpiece, Opticks,

which expanded
on his work with light.

At the end of this book,

Newton finally wrote up some
his key ideas about calculus

40 years after
they were conceived.

And although
he had given up alchemy,

he continued to devote
himself to theology.

Right up to his death,

he tried to keep his heresy
as secret as possible,

and he thinks, "There's no point
trying to convince these people

"of what I'm doing, because
the time is not right.

"These people aren't fit
to receive

the kind of word
that I'm giving out."

Newton died in 1727.

He was 84 years old.

He was buried among kings
and queens in Westminster Abbey

beneath a monument to his
scientific achievements...

His alchemy and passionate
but heretical religious beliefs

virtually unknown.

Now, 2½ centuries later,

a new picture
of Sir Isaac Newton is emerging

along with a new understanding
of the roles

that science, religion and
alchemy played in his life.

He sees his world as one world,

he sees his pursuit of truth
as one pursuit,

and whether it takes him
to books of theology

or to books of nature,

whether it be books of astronomy
or books of alchemy,

it doesn't matter to him.

What Newton does
is brilliantly to use

the tools appropriate to every
field in which he worked.

He's an ingenious
and energetic builder

who's astonishingly brilliant
at composing gorgeous monuments

of the most
intensely clever design.

Sometimes these appear
as great books,

like the Principia itself.

Sometimes they appear
in experiments.

But we would be wrong
to look for a single key

which unlocks the whole mystery
of Isaac Newton.

The man was a complete genius.

I mean, people like Newton...
if I shoot off the hip,

maybe once in 500 years...
At best.


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