All language subtitles for BBC.Science.and.Islam.1of3.HDTV.x264.AC3.MVGroup

My name is Jim Al-Khalili
and I'm a professor of physics
at the University of Surrey.

Studying the innermost secrets of
atoms and their nuclei has been
at the heart of my working life.

But there's another side to me...

I was born and grew up in Baghdad,

to an English mother
and an Iraqi father,

but left Iraq with
my family in the late '70s

when Sadam Hussain came to power.

By then, science was already
my great passion in life.

As I studied it further,
I saw myself fully part

of the Western tradition, inspired
by names like Newton and Einstein.

But buried away was this nagging
feeling that I was ignoring part
of my own scientific heritage.

I still remembered my schooldays
in Iraq and being taught of a
golden age of Islamic scholarship.

That between the 9th and 12th
centuries,

a great leap in scientific knowledge

took place in Baghdad, Damascus,
Cairo and Cordoba.

So, I want to unearth this buried
history

to discover its great figures

and to assess exactly what their
contribution to science really was.

Are there medieval Muslim scientists
who should be spoken of

in the same breath as Galileo,
Newton and Einstein?

And crucially,
what is the relationship

between science and Islam?

My journey into the science
of the medieval Islamic world

will take me through Syria,
Iran and North Africa.

'I started in the backstreets
of the Egyptian capital Cairo,

'with the realisation that that the
language of modern science still has
many references to its Arabic roots.

'Take scientific terms like
algebra, algorithm, alkali.

'I instantly recognise
these words as Arabic.

'And these are at the very
heart of what science does.

'There would be no modern
mathematics or physics without
algebra.

'No computers without algorithms
and no chemistry without alkalis.

'Surprisingly few people in the west
today, even scientists, are aware
of this medieval Islamic legacy.

'But it wasn't always so.

'From the 12th to the 17th century,

'European scholars regularly refer
to earlier Islamic texts.'

I have here copies of some pages
of the book Liber Abacci by
the great Italian mathematician,

Leonardo Pisano,
otherwise known as Fibonacci.

What's fascinating is that on page
406 is a reference to an older text

called "modum algebre
et almuchabale'

and in the margin is the name
Maumeht,

which is the Latinised version
of the Arabic name, Mohammed.

The person he's referring to
is Mohammed ibn Musa Al-Khwarizmi.

In fact, Arabic names crop up
in many medieval European texts

on subjects as varied as map-making,
optics and medicine.

But I want to start with
Al-Khwarizmi, because his work

touches on a crucial aspect of
all our lives today.

It's thanks to Al-Khwarizmi
that the European world realised
that their way of doing arithmetic,

which was still essentially
based on Roman numerals,

was hopelessly inefficient
and downright clunky.

If I asked you to multiply
123 by 11,

you may even be able
to do it in your head.

The answer is 1,353.

But try doing it
with Roman numerals,

you'd have to multiply
CXXIII by XI.

It can be done, but trust me,
it's not fun.

Al-Khwarizmi showed Europeans

that there's a better way
of doing arithmetic.

In his book entitled
The Hindu Art Of Reckoning,
he describes a revolutionary idea.

You can represent any number
you like

with just ten simple symbols.

This idea of using just ten symbols,
the digits from one to nine,

plus a symbol for zero to represent
all numbers from one to infinity

was first developed
by Indian mathematicians

around the 6th century and
I can't overstate its importance.

Here are the numbers
in Indian Arabic numerals.

Wahid, ithinin,
thalatha, arba'a,

khamsa, sita, saba'a, thamania,
tisa'a.

And here are the numbers we're more
familiar with in the West.

One, two, three, four, five,

six, seven, eight, nine.

And you can see the similarity
between these numbers

and particularly
between the numbers two and three.

If I tip this sideways,

you can see how they look
like numbers two and three.

And what's powerful about these
digits, this numerical system

is how it simplifies
arithmetic calculations.

'But Al-Khwarizmi and his colleagues
went further than just translating
the Indian system into Arabic.

'They created the decimal point.'

This text, written just a century
after Al-Khwarizmi's,

is by a man we know only as
Al-Uqlidisi.

Here he shows that
the same decimal system

can be extended to describe not just
whole numbers but fractions as well.

The infinity of possibilities
that lie in between the integers.

Here is a copy of
Al-Uqlidisi's manuscript

where he showed
how the decimal point

is used for the very first time.

He describes it by using a dash.

Here are the digits 17968,

and there's a small dash over the
nine indicating the decimal place.

The idea of the decimal point is
so familiar to us,

that it's hard to understand
how people managed without it.

Like all great science,

it's blindingly obvious
after it's been discovered.

'The story of numbers
and the decimal point hints

'that even 1,000 years ago science
was becoming much more global.

'Ideas were spreading, emerging out
of India, Greece or even China

'and cross-fertilising.

'And looking on a map that shows
where people lived 1,000 years ago

'gave me my first insight
into why medieval Islam

'would play such an important role
in the development of science.

'Now look at which city lies at the
centre of the known world,

'a place where the widest range of
peoples and ideas

'were bound to collide.

'It's the city where I was born,

'the capital of the Islamic empire,
Baghdad.

'Recent events mean I can
no longer visit the city,

'but these are the home movies of my
cousin Farris, filmed in the 60s.

'The Baghdad we knew then
looked nothing

'like the bomb-wrecked city
it is now.

'I certainly grew up proud
to be associated

'with one of the world's
greatest cities.

'Baghdad was founded in 762 AD
by the caliph Al-Mansur.

'His aim was to make it the glorious
capital of a brand new empire

'united by Islam,
the rising religion of the time.'

The Abbasid caliphs had claimed
their right to rule by declaring

that they were directly related
to the prophet Mohammed,

who had founded the new religion
over 100 years earlier.

But in that short time,

the armies of Islam
had conquered a vast territory.

Starting in a small area
around Medina,

they moved rapidly
out of the Arabian peninsula

and within a few decades
had taken control of the Levant,

North Africa, Spain and Persia.

I think one must bear in mind
that this is an era

in which people believed in God,

and the dramatic successes
of the Arabs

as they poured out of Arabia

were such that a lot of people
did observe

and say they must have God
on their side.

This must be the true god,
and some people did convert,

or if they didn't convert,

they did submit to Arab-Muslim
political control for that reason.

By the early 8th century, Islamic
caliphs ruled a vast territory.

And like most successful emperors,
from Caesar to Napoleon,

they understood that political power

and scientific know-how go
hand in hand.

There were many reasons for this.
Some were practical.

Medical knowledge could save lives.

Military technology could win wars.

Mathematics could help deal
with the increasing complexities

of the finances of state.

Islam as a religion also
played a pivotal role.

The prophet himself had told
believers to seek knowledge

wherever they could find it, even
if they had to go as far as China.

And many Muslims, I'm sure,
felt that to study

and better understand God's creation
was in itself a religious duty.

But there were other less
edifying motives at play.

To many in the ruling elite
of the Islamic Empire,

knowledge itself
had a self-serving purpose.

Because possessing it was seen as
proof of the new empire's
superiority

over the rest of the world.

But with military and
political success, the Islamic
caliphs faced an inevitable problem.

How do you sensibly govern
a hugely diverse population?

Although some of the empire
had converted to Islam,

they were still separated
by huge distances

and adhered to many
different traditions and languages.

In the 8th century AD, the empire's
leader, Caliph Abdul Malik,

had to find a way of administering
this mish-mash of languages.

Like all the great figures of the
Islamic empire, Al-Malik lived in
a culture without portraiture.

All we have are later impressions
of what he might have looked like.

His solution was sweeping in scale

and, inadvertently,

laid the foundations of
a scientific renaissance.

It was this Abdul Malik who said
this bureaucratic chaos has to stop.

We cannot continue
to run the government

and govern all this span of land
with this tower of Babel languages.

He wanted to govern it
with a uniform language

and that language was one
he wanted to understand,

so he demanded that it be in Arabic.

But the choice of Arabic as the
common language of the Empire went
beyond administrative convenience.

The decision had extra force
and persuasiveness,

because Islam's holy book the Qur'an

is in Arabic, and Muslims
therefore consider Arabic

to be the language of God.

The words of the Qur'an
are so sacred

that its text hasn't changed
in over 1,400 years.

By comparison, English has changed
dramatically in just 700 years.

To our ears,
Chaucer is almost unintelligible,

whereas any Qur'an can be understood
by anyone who reads Arabic.

Making copies of the Qur'an
has always been a specialised

and highly respected job
since the foundation of Islam.

Calligraphy expert Nayef Scaf,
who lives in the Syrian capital

Damascus, writes for mosques and
in madrasahs all over the country.

These are words he's found
himself writing over and over again.

Words of great
significance for Muslims.

They're the opening line
to each chapter in the Qur'an.

So, what it says is,
"Bismi llahi ar-rahman ar-rahim,

which means, "In the name of God

"the most gracious
and the most merciful."

HE SPEAKS ARABIC

He's saying that the complexity
of Arabic calligraphy

was enforced onto them because
of the spread of Islam,

because they were worried
that the meaning of the words

in the Qur'an would be lost.

If it was read by people who don't
speak Arabic not only would they
misinterpret it,

they wouldn't be able to
distinguish between letters.

So, not only did they add
dots on certain letters,

but also lots of squiggly lines

which change the sound
of the vowels.

It was something they put into
place to ensure that people were

able to have the right pronunciation
when they read the Qur'an.

The consequences
for science were immediate.

Scholars from different lands

who previously had no way
of communicating

now had a common language.

And it was a language that was
specially developed to be precise

and unambiguous, which made it ideal
for scientific and technical terms.

What this meant was the summoning
into existence

of a vast intellectual community,

where scholars from very different
parts of the world

could engage in dialogue,
comparison, debate, argument,

often very fierce argument
with each other.

It was possible for scholars based
in Cordoba in southern Spain

to engage in literary
and scientific debate

with scholars from
Baghdad or from Samarkand.

But I can tell you
that scholars aren't motivated
by the love of knowledge alone.

There's nothing like a large
hunk of cash to focus the mind.

By the early 800s, the ruling
elite of the Islamic empire

were pouring money into
a truly ambitious project,

which was global in scale

and which was to have
a profound impact on science.

It was to scour the libraries
of the world for scientific

and philosophical manuscripts
in any language,

Greek, Syriac, Persian and Sanskrit,

bring them to the empire
and translate them into Arabic.

This became known
as the translation movement.

The effort scholars put into finding
ancient texts was astonishing.

And one key reason for this is
that bringing a book to the caliph,

which he could add to his library,
could be extremely lucrative.

The story goes that the caliph
al-Ma'mun was so obsessed

that he'd send his messengers
out of Baghdad,

far and wide to distant lands,
just to get hold of books

that he didn't possess,
for the translation movement.

And anyone who brought him back
a book that he didn't have,

he'd repay them its weight in gold.

To give some sense of the extent of
the activities between 750 and 950,

somebody called Al Nadim, who wrote
a list of the intelligentsia

of the Abbasid era,
lists 70 translators,

so it was quite a large cohort of
people involved in translations.

And obviously, he only named
the well-known translators.

They could get up to
500 gold dinars a month,

which is probably around $24,000.

Which is a huge sum of money
for what they were doing.

It was a very prestigious,
well-paid, well-patronised activity.

And motivating this global
acquisition of knowledge

was a pressing practical concern,

one that rarely crosses
our minds today.

This is the new Library
at Alexandria, in Egypt.

But fresh in the memory of many
in the empire was the story

of the destruction
of the original library

at Alexandria centuries earlier,

and the shocking loss of thousands
of years of accumulated knowledge.

One of the things that
we tend to forget,

because we live in a age
of massive information storage

and perfect communication
more or less,

is the ever present
possibility of total loss.

That was very important for Islamic
scholars.

They knew extremely well
that writings could be forgotten

or buried or burnt or destroyed,
that cities could pass away.

What we see in Baghdad or Cairo
or Samarkand

is exactly the gathering together
and translation, analysis,

accumulation, storage and
preservation of material

which they were well aware
could be lost forever.

And if there was one branch of
knowledge that everyone from the
mighty caliph to the humble trader

wanted to preserve and enhance,
it was medicine.

These were, after all,
times when few lived to old age.

Writings from the time remind us
that what we might consider

a relatively minor infection today
could be a death sentence.

Religious teachings then
were not just a source of comfort.

They were a constant reminder
that we should never give up.

In the Hadith which is the collected
sayings of the Prophet Mohammed,

it says....
HE READS ARABIC

Which means that God
didn't send down a disease

without also sending down a cure.

It's statements like this that lead
Muslims, even today, to believe

that cures for all diseases
are out there somewhere

and that we need to search
to find them.

'To assess how this optimism
actually affected Islamic medicine,

'I met up with Dr Peter Pormann
in the Syrian capital, Damascus.

'He's a leading expert
on Islamic Medicine,

'who spends much of his time
researching

'here in the Middle East.'

What people don't realise is
that the history

of Islamic medicine is really
the history of our medicine,

because our medicine,
the university medicine,

we used until the 19th century,

it was based to a large extent on the
work of all these Islamic physicians.

Islamic medicine built extensively
on the foundations

laid by the ancient Greeks.

The most highly prized and among the
first to be translated into Arabic

were the medical manuscripts of the
3rd century Greek physician, Galen.

Galen believed that a healthy
body was one in balance.

A balance of four types of fluids
called humours,

which circulate through the body

and any one of which,
if out of balance,

would cause illness
and a change of temperament.

The four humours were yellow bile,

which, if in excess, would cause
the patient to become bilious

or bad-tempered and nauseous.

Blood. Too much of which would cause
the patient to become sanguine,

or cheerful and flushed.

Black bile, which in excess
would cause the patient

to become lethargic or
melancholic or even depressed.

And...phlegm, which in excess

would cause the patient to become
phlegmatic or apathetic

and emotionally detached.

Galen argued that illnesses
are caused by an imbalance

in one of the humours,

so the cure lies in draining
the body of some of that humour.

He recommended techniques
like cutting to induce bleeding

or using emetics to induce vomiting.

'But Islamic doctors were acutely
aware that Galen and Greek medicine

'were only one source
of medical knowledge.

'There were other traditions of
medicine that they were equally keen

'to incorporate into
their understanding
of how the body functioned.

'Medieval Arabic texts refer
to wise women, folk healers
who provided medical drugs.

'This tradition continues today,
as I found when I came across one

'for myself in the back
streets of Hammamat in Tunisia.

'This is Arafez Nabil.

'She's been running her shop
selling medicinal herbs
and spices for over 20 years.

'She believes that her remedies
can cure

'a wide range of medical ailments.'

'In the backstreets of Tunisia
this knowledge is still being used.

'But medieval Islamic doctors were
also aware of other traditions
of medicine from China and India.

'And yet another tradition
of medical guidance
came from within Islam itself,

'and takes some of its ideas from
the Qur'an

'and some from the collected sayings
of the Prophet, the Hadith.

'In a bookshop in Monastir
in Tunisia, I found a copy

'of a very popular book available
right across the Islamic world.'

This book is called
The Prophet's Medicine

and you can see how old it is.

The author was born
between 691 and 751 Hijri,

which places him the 14th century.

Here's an interesting bit,
where it deals with the plague.

HE READS ARABIC

It says, "If you come across a land
where the plague has come down,
then do not enter that land.

"And if the plague comes down onto
your land and you are there,

"then do not leave your homes
in the hope of escaping it."

So that sort of
makes a lot of sense.

But here's quite an amusing part.

It deals with epilepsy and it says
that the Greeks or Galen believes

that epilepsy originated in the
brain, however they were ignorant.

They didn't realise the true cause
of epilepsy, which is the possession

of the body by evil spirits.

And it talks about the cure
for epilepsy being exorcism.

'Hardly scientific.

'But Islam's most tangible
contribution to medicine

'is less in its specific remedies

'and more in
its over-arching philosophy.

'It is, after all, a religion
whose central idea

'is that we should feel
compassion for our fellow humans.

'And accompanied
by Dr Peter Pormann,

'I'm going to see a physical,
bricks and mortar manifestation

'of medieval Islamic compassion.

'This is the Nur al-Din hospital,

'the leading hospital
of the Islamic empire,

'built here in Damascus
and now a museum.'

THEY GROAN WITH EXERTION

This was built in the 1150s, 1154,
I believe.

One of the ideas which are stipulated
in Islam

is the idea to be charitable
and charity. Zakat.

Exactly, and it's an obligation
to give alms and stuff like that.

So, if you're a ruler or you have a
lot of money, what you could do is...

You could really be charitable.
..and set up a nice hospital
like this one.

And within the hospital, Islam
actively encouraged

a high degree of religious
tolerance,

something we take for granted
in modern secular society.

The hospital was open
to all communities,

so you'd have Christians and Jews
and Muslims obviously

and maybe other denominations both as
patients and also as practitioners.

Like a Christian studies
with a Muslim, a Muslim says
my best student was a Jew,

and so the medicine which was
practised here transcended religion.

Typically, how many
physicians would there be?

Well, it depends.
For certain hospitals,

we hear figures of 24 or 28
physicians. Wow.

Physicians would do the rounds
in the morning.

Do the prescriptions.

Things haven't changed
over the ages, yeah.

'As a result
of the translation movement

'those physician now became aware
of the latest remedies

'from as far away
as India and China.

'And as the new drugs filtered
in from the rest of the world,

'hospitals started to set up
a new kind of facility

'within their walls - the pharmacy.'

So, this notion of a pharmacy in a
hospital, is that a new innovation?

The whole package, certainly
that's new, and what is interesting,

if you look for innovation
on the level of pharmacy,

if you look at Baghdad
or even Damascus,

it's at this crossroad of cultures.
So loads of new things come in,

like musk, for instance, you have
Indian drugs, there's an Indian pill,
for instance,

which is good for headaches
and bad breath,

but also gives you sexual
appetite, and stuff like that.

Cures your headache,

gives you...fresh breath,
and gives you...

So it's like toothpaste,
Viagra and aspirin.

That's right. All in one. Fantastic.

So, let's walk in here.

'Peter wants to show me perhaps
the most ghoulish aspect of
Islamic medicine, surgery.'

Here you have
a wonderful illustration.

This appears to be the first
anatomical illustration in history.

You see it says "adala",
which means muscle.

So, these are the different
muscles, which move the eyelids.

So it was understood
that the muscles controlled the lens
and the eye. Absolutely. Yes. Yeah.

Move the eyelid, and stuff like that.

The other thing we have here,
which is really nice,

is we have some ophthalmological
instruments,

for instance it's a hook,

could be used to pull back
your eyelid, that sort of thing.

These instruments were very useful
to the doctor.

Although these tools might look
crude, eye surgery was one of
Islamic medicine's great successes.

One innovation was to improve
an older technique for curing
cataracts called "couching"

which, in their hands,
had a success rate of over 60%.

In a living subject,
the cornea would be clear.

Then you'd be able to see
the pupil clearly, with the cataract
sitting behind the pupil.

'To see how couching stands
the test of time, I'm meeting up
with eye surgeon Mr Vic Sharma.'

The cataract is the lens inside
the eye, which sits behind the pupil.

As with time and age the cataract,
the lens gets cloudier and cloudier,

that's what is referred to
as a cataract.

'I've brought along a replica
of a medieval couching knife

'and a description of the treatment
by Albucasis,

'which is the Latin name
for the great 10th-century
Islamic surgeon Al-Zahrawi.'

He says, "You take the couching
needle in your right hand, if it be
the left eye..." and so on.

"Then thrust the needle firmly in,
at the same time rotating it with
your hand

"till it penetrates the white of
the eye and you feel the needle has
reached something empty."

So, he's talking about
how to dislodge. Exactly.

So, maybe you can show me.
We've got some eyes here.

Yeah. I'll give it a try.

And what they would have done
is attempted to go in

by the white of the eye, at the edge,

where the cornea is, and what they
attempted to do was sweep around,

try to break those ligaments of that
lens

and get the lens to drop away
from the pupil,

to allow more light to enter in
through pupil

and to brighten the subject's vision.

You haven't got the capacity to
focus. Yeah, you have no lens now.
That was a big problem

until people starting compensating
for that with specs later on.

Right. What is your feeling about
how advanced and successful...?

Well, they were in the general
ball park, the right place.

They were trying to remove the
cataract away from the visual axis.

They had some understanding
of the anatomy of the eye

and that the lens was
behind the pupil

and that's what was causing
the visual loss.

And so removing that... That general
principle is still the same.

There are accounts of it still
being used in certain parts
of the world presently.

'Looking back at medieval Islamic
medicine with modern scientific eyes
is frustrating.

'They take as true many things
we know to be nonsense,

'but on the other hand, their desire
to deal with this vast subject

'logically and systematically
is admirable

'and truly marks a break
with the past.

'One Islamic scholar,
more than any other,

'embodies the synthesis
of religion, faith and reason.

'His name was Ibn Sina, or Avicenna,
as he's known in the West.

'He was a polymath who clearly
thrived in intellectual
and courtly circles.

'In 1025, he completed this...

'Al-Qanun fi al-Tibb
or the Canon Of Medicine.

'In it Ibn Sina collated and
expanded on all

'that had gone before him,

'medical ideas from Greece to India,
and turned them into a single work.'

So how would you place this book
in an historical context?

Oh, it's hugely important.

There are few books which are
as important as the Canon,

because what this encyclopaedia does,
it kind of, you know,

sweeps away everything
else, it becomes a text book,

it supersedes a lot of other texts.

People even complain, like, it's so
good, it's so tightly organised,

so easily accessible that, you know,

people forget to read the Greek
sources and the Arabic translations.

This whole first book, this is
the first book, it contains
what we call the general principal,

so it's all about how the human body
works, how diseases work in general.

The second book contains diseases
right from tip to toe,

so he starts with the diseases
of the head

and then he moves down, like the
eyes, the ears, the nose, the mouth.

And he...normally they end up
at the sexual organs.

'At first sight the sheer
ambition of the three volumes
is hugely impressive.

'Here's an attempt at diagnosis
and cure for diseases

'as diverse as depression,
meningitis and small pox,

'and there's even detailed
chapters on more common problems.'

So, for instance, here you have,
like, headaches.

Different kinds of headaches.

HE READS ARABIC

So, headaches caused
by pleasant fragrant smells.

And then he's also got, erm...
HE READS ARABIC

So, hangovers.
DR PORMANN READS ARABIC

Headaches from sex. Is that right?

I mean, it hasn't happened to
me yet, but I mean, you know...

Let's see. So the treatment of
headache caused by sex.

HE READS ARABIC

So if somebody is befallen by,

suffers from a headache after sex

and he also has a repletion, like,
so he has too many superfluidities
or something like that...

HE READS ARABIC

He has to first resort to
venasection, or blood letting.

HE READS ARABIC
Then you should use purging.

In...
HE READS ARABIC

For both of them, blood letting
and purging are necessary.

A lot of the stuff in here
sounds like nonsense,

because this is not modern medicine.
No, it's not.

How long was this taken seriously?

Well, the fundamental ideas
contained here about how
the body works, I mean...

they hadn't changed
until the early 19th century.

There was progress on certain levels,

but the essence was the same.

And then came the big break,
with the discovery of bacteria
and viruses and things like that.

From the second half
of the 19th century onwards,

medicine was totally revolutionised.

'Ibn Sina's Canon of Medicine
is a landmark in the history
of the subject.

'Although much of the medical
science it espouses we know now to
be terribly misguided,

'its value lies in accumulating
the best knowledge in the world

'at the time into one accessible,
organised text.

'The Canon would give future
generations something to rewrite.'

Cataloguing the world's
medical knowledge has
clear and obvious benefits.

But the Islamic empire's obsession

to uncover the knowledge
of the ancients

went beyond practical matters,
like medicine.

Many, like the Caliph Al-Mamun,

believed that the people of
antiquity

possessed dark, even magical powers.

And, what's more, new evidence is
coming to light to show just

how hard Islamic scientists worked
to rediscover them.

'To find out about that story, I
have to visit the harsh burnt yellow

'of the Sahara desert in Egypt.

'There I am to meet an academic

'who wants to show me
how the translation movement

'took the Arabs to Egypt
on a quest to break a code,

'which they thought hid the secret
of the dark art of alchemy.

'This is Saqqara, a necropolis, or
graveyard, of the ancient pharaohs.

'Over a ten-acre site,
it's a collection of burial chambers

'and step pyramids that were built

'in the third millennium
before Christ.

'These are said to be among the
oldest stone buildings in the world.

'Archaeologist Dr Okasha
El-Daly is my guide.

'He was about to reveal the most
astonishing story of my journey
so far.'

Oh! Ho ho. Look at that.

'Like most people,
I believed that Egyptian hieroglyphs

'had remained completely
undeciphered until the 19th century.

'Then came the chance discovery
of the famous Rosetta Stone.

'This stone had the same inscription

'written in both
hieroglyphs and Greek.

'It provided the crucial clues,

'which British and French scholars
used to decipher

'the writings of ancient Egypt.

'That's the usual story one hears.

'But Dr El-Daly has made a discovery
that dramatically alters it.

'He has recently unearthed a number
of rare works

'by the Islamic scholar
Ibn Wahshiyah.

'What he did was to figure
out a correspondence

'between hieroglyphs like these
and letters in the Arabic alphabet.'

If you look here, for example, at Ibn
Wahshiyah's manuscript, he's giving
us the Egyptian hieroglyphic signs...

And Arabic letters underneath.

Yes. And the phonetic
value in Arabic underneath.

Look very carefully at this one,
says "seen" underneath that seat.

Yes. Now, look at this seat here.

That seat in Egyptian hieroglyphic
is used for the sign "S", "seen",
which is what you see here, "seen".

That is the name of the god Osiris.

Osiris. Oh, with an "S".

This is the letter "H".

This one here... This is the "hah".

The water wave is the letter "N",
or "noon" in Arabic.

"T" and the letter "F"... These are
all letters? These are all letters.

'But how did
he decipher the hieroglyphs?'

The one good thing about the early
Arabic scholars is their ability

to link ancient Egyptian language,
we call hieroglyphics,

to link it with
their own contemporary Coptic.

They realised that Coptic is nothing

but the later stage
of ancient Egyptian language.

'They realised this
because the translation movement

'had literally placed hundreds
of Coptic texts into their hands.

'The scholars could now see
a direct link

'between hieroglyphs and Arabic.'

What fraction of these symbols would
have been correctly deciphered?

They got about 14 letters.
They cracked more than
half of Egyptian hieroglyphics.

So, that was a remarkable achievement
for people of the 10th century.

Well, that's probably the biggest
revelation for me so far
on my travels,

that Egyptology didn't begin
in the 19th century.

Yet again,
it seems that Islamic scholars

actually cracked hieroglyphics and
they cracked it for strange reasons.

They cracked it because they were
interested in astrology and alchemy.

But here is another example of this
amazing translation movement.

They weren't just translating Greek
and Indian and Persian texts,

they were translating
Egyptian hieroglyphics as well.

Absolutely incredible.

'Unfortunately
for the Caliph Al-Mamun,

'the hieroglyphs
contained no alchemical secrets.

'But what this story reveals to me
is the insatiable curiosity

'Islamic scholars had
about the world.

'They were desperate
to absorb knowledge

'from all cultures purely on merit,

'with no qualms about the places
or religions from which it came.'

Most intellectual traditions,
including, if I may say so, our own,

tend to work very hard
to keep everybody else out.

Whereas here we have an example of
an enterprise which is desperate,

curious, to turn itself into a net
importer of intellectual product.

And that's a very important lesson
for the history of the sciences.

'I was soon to see
just how dramatically

'this fuelled scientific innovation,

'but it's worth remembering
that the translation movement

'wasn't just
about science and medicine.

'As the capital Baghdad sat in the
centre of a vast successful empire,

'it became home to an extraordinary
flourishing of all kinds of culture.

'For this is the time described
by One Thousand And One Nights,

'of great and generous caliphs,
magic carpets, great journeys,

'but also ambitious buildings,
music, dance,

'storytellers, and the arts.'
HE CHANTS IN ARABIC

CHEERING AND CLAPPING

Baghdad was such a cultured and
vibrant city that one traveller

of the time wrote, "There is none
more learned than their scholars,

"more cogent than their theologians,

"more poetic than their poets,
or more reckless than their rakes!"

It really must have felt
like Baghdad and the Arabic Empire

were the world leaders
in civilisation and culture.

To be part of that city's growing
intellectual elite must have
been as exciting as it gets.

It was a new Muslim city.

It only started to be built in 756

so it has that sense of being on the
frontier of being new and different.

It was full of courtiers
and nouveau riche individuals

who were trying to
make their way at the Abbasid court

and it is the sort of place

where innovation is valued and
appreciated.

At the heart of the city's
intellectual life

was a system called the majlis.

The word "majlis" could perhaps
be best translated

as "salon" or "talking house".

In 9th century Baghdad what this
meant was that city's ruling elite,

the Caliph, his courtiers,
the generals and the aristocracy,

would hold regular meetings,

you might call them seminars
or discussions,

during which the city's cleverest
men, the philosophers, theologians,

astronomers and magicians,

would gather to discuss
and debate their ideas.

It was not the case that people
were expected to adhere

to a particular line
or adopt a particular religion.

They were allowed to express

their own views and sentiments
very freely.

The point was that they should
do so in elegant Arabic

and with good logical reasoning.

The effect of the majlis

was to create a heady mix
of money and brains,

with the best minds in the empire
swapping ideas

while simultaneously engaged in
fierce competition for patronage.

'It's at this point my investigation
into the first wave
of Islamic science

'returns me to the man we first met
at the beginning of this story

'in the back streets of Cairo,
the great mathematician

'who brought the West
the decimal system.'

Out of the very heart of this
intellectual whirlwind

came Al-Khwarizmi, mathematician,
astronomer, courtier

and favourite
of the Caliph al-Mam'un.

He was a product of a his age,
an emigre from Eastern Persia

into Baghdad, surrounded by books,

well-versed in learning from Greece,
Persia, India and China,

and fearless in his thinking.

'Al-Khwarizmi brought together
two very different mathematical

'traditions and synthesised them
into something new.'

The capacity to
have on your desk simultaneously

two very different kinds
of mathematics

presses on models
of what counts as calculation,

what counts as measurement,

and I think accelerates
the process of intellectual change.

The first of these traditions
came from the Greek-speaking world.

Greek mathematics dealt mainly
with geometry,

the science of shapes like
triangles, circles and polygons,

and how to calculate
area and volume.

The other great mathematical
tradition

Al-Khwarizmi inherited
came from India.

They'd invented
the ten-symbol decimal system

which made calculating much simpler.

Thanks to the translation movement,

Al-Khwarizmi was in the
astonishingly lucky position

of having access to both Greek
and Indian mathematical traditions.

He combined geometrical intuition

with arithmetic precision,

Greek pictures and Indian symbols,

inspiring a new form of mathematical
thinking that today we call algebra.

'As a physicist, I've spent
much my life doing algebra

'and I can't overstate
its importance in science.

'But it is a strange idea.

'I remember being perplexed when my
maths teacher first started talking

'about mathematics not using numbers
but with symbols like x and y.

'It's an incredibly liberating idea,

'because it allows you to solve
problems without getting bogged down

'in messy numerical calculations.'

So we have here
this priceless manuscript,

HE READS ARABIC
Al-Khwarizmi's book.

'Professor Ian Stewart has studied
algebra

'for much of his working life.

'Together we looked at an early copy
of the book

'in which the idea
really took form.'

I see here, although it's written in
the margins, the title of the book.

Al-Jabr w'al-Muqabala, so that's the
first time the word Al-Jabr appears.

Algebra. That's where
our world algebra comes from.

Now, what I found very early on
is that he said,

"I discovered that people require
three kinds of numbers,"

HE READS ARABIC
So, roots, squares and numbers.

So, what is he trying to do here?

This is what we would now
call x and x squared.

This is quadratic equations.

This really is algebra.

So, he's setting you up for a book

about how to solve
equations by algebraic methods.

Now, quadratic equations, I thought
were around and being solved

long before Al-Khwarizmi back
in Babylonian times.

So what's
the big deal about this book?

It's the point of view.

He treats root and square as if
they were objects in their own right.

They're not just some number

that we are trying to find out,

they are a process you apply.

What Al-Khwarizmi is thinking of

is square means take the root
and multiply it by itself.

And that recipe is true,
whatever the root might be.

If it's five, it's five times five,
it's 25.

If it's three,
it's three times three.

He's giving you a general recipe,
now called an algorithm.

After him.

R...r...right, algorithm comes
from...

Its another world that comes
from Al-Khwarizmi.

Now, he talks about this
procedure on the next page.

You take the number multiplying
the root and then you halve it,

and then you multiply it by itself

Then you add it to the other number
and take the square root.
That's the algorithm, is it?

That's right and this is
where you see the difference,

because previous writers
on the subject

would have said things like,

"Take half of 10, which is 5,
square that, which is 25."

And then they'd do another problem,

take half of 12, which is 6,
and square that, which is 36.

And they'd run you through
the same process over and over
again with different numbers.

And it would be up to you to infer
how to do it on the next problem.

But he doesn't do that.
He doesn't do that.

He says, "Take half the root,

"whatever the root is,
take half the root."

So half the root is an object.

If the root is an object,
so is half the root.

So you don't have to have in your
mind what that root stands for.

You can forget about
what it stands for.

When you come to square it, you
just know to square the thing,
I don't care what the thing is.

So, you abandon temporarily
this link with specific numbers,

manipulate the new objects according
to the rules his book is explaining.

And then the numbers that these
objects are represent

in your particular problem will
miraculously appear at the end

and you'll end up with x = 3
or whatever it is.

So, how revolutionary do you regard
Al-Khwarizmi's work?

He made it possible for algebra to
exist as a subject in its own right,

rather than as a technique
for finding numbers.

The least interesting bit of an
algebraic calculation is when you get
to the end and discover that x = 3.

It's the route you take to get there.

But if it was a special route and
a different route for each problem,

that wouldn't be interesting either,
it would just be a big mess.

There's a beautiful general series
of principles,

and if you understand those,
then you understand algebra.

What is the true global
importance of algebra?

It's been used throughout the ages
to solve all sorts of problems.

Let the mass of a cannon ball
be 'm', let the distance
it has to travel be 'd'.

You use algebra to work out
the optimum angle

you have to point your cannon.

That sort of knowledge wins wars.

'Or let's call the speed of light
'c',

'the change in the mass of an atomic
nucleus 'm',

'and then calculate the energy
released

'with the following algebraic
formula, E=mc2.

'Mastery of that information
truly is power.

'Algebra has helped
create the modern world.

'Our science is
unimaginable without it.

'It sums up so much
that was remarkable

'about medieval Islamic science,

'taking ideas from Greece and India,
combining and enhancing them.

'Similarly, modern medicine
owes a considerable debt

'to the work of the Islamic
physicians.

'But I think the real story of what
happened to science

'in the Islamic world in 8th and 9th
centuries

'tells us more than any single
discovery.

'What it really tells us

'is about the universal truth
of science itself.'

I believe that the first great
achievement

of the medieval Islamic scientists
was to prove

that science isn't Islamic,
or Hindu or Hellenistic,

or Jewish, Buddhist or Christian.

It cannot be claimed
by any one culture.

Before Islam,
science was spread across the world.

But the scholars of medieval Islam

pieced together this giant
scientific jigsaw,

by absorbing knowledge

that had originated from far beyond
their own empire's borders.

This great synthesis produced
not just new science,

but showed for the first time

that science as an enterprise

transcends political
borders and religious affiliations.

It's a body of knowledge
that benefits all humans.

That's an idea that's as relevant
and as inspiring as ever.

'In the next episode, I investigate
how one of the most important ideas

'in the world arose
in the Islamic empire.

'I discover how mathematics and
experimentation fused together

'as the empire embraced
a medieval industrial revolution.

'And in Cairo, I find out
how these ideas

'led directly to today's
world of science and technology.'

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