Empire: World History - 193. Empire of Numbers: The Indian Origin of Arabic Numerals

Episode Date: October 9, 2024

Often called Arabic numerals, the modern number system we use today actually originates in India. Whilst in the west they were using Roman numerals, in India they were using numbers 1-9. Then, the great Brahmagupta in the 7th century made one of the most monumental developments in human history. He invented zero in its modern form. Therefore, these basic rules of mathematics for the first time allowed any number up to infinity to be expressed with just ten distinct symbols: the nine Indian numbers plus zero. Rules that are still taught in classrooms around the world today. This step was a major advance that had never previously been attempted elsewhere and it was this Indian reincarnation of zero as a number, rather than just as an absence, that transformed it and gave it its power. From India, this development then travelled along the Golden Road and into the heart of Barmakid Baghdad.  Listen as William and Anita discuss the origins of the Empire of Numbers. To buy William's book: https://coles-books.co.uk/the-golden-road-by-william-dalrymple-signed-edition Twitter: @Empirepoduk Email: [e-mail] Goalhangerpodcasts.com Assistant Producer: Tabby Syrett Producer: Callum Hill Exec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

If you want access to bonus episodes reading lists for every series of Empire, a chat community. Discounts for all the books mentioned in the week's podcast, add free listening and a weekly newsletter, sign up to Empire Club at www.mpowerpoduk.com. Hello and welcome to Empire with me, Anita Arnh. And me, William Duremple. Now, over the next two episodes, we're going to be doing something very, very hilarious. We are going to be talking to my lovely friend who I adore William Duremberg who is an amazing writer and the Golden Road soaring like a phoenix in the sky.

But he's going to be talking about numbers. And if anyone knows William at all, the panic, the sweat, the beads of sweat on his head when you ask him to add two fairly small and innocuous numbers. It is true that math are not my strongest card and that I not once but twice fail, my math low level at the age of 15. Did you? Did you? Yes, I did.

Oh, good. What did your parents say? Well, they also knew that I'm basically completely enumerate, so they weren't enormously surprised. Is that true? Oh, God, you know, if you had Indian parents, the true story, I think I once got a, what was it, like a high mark in a math test. I hated maths, but I did it. And I think I got like sort of 85%, which I was dead chuffed about.

And I had my dad on the phone to an uncle going, no, she's done really badly. It's only 85. Only 85%. What? And that, dear listener, is the difference between an Indian and a Brit. My kids, incidentally, when they came, they went to Indian schools in Delhi and then came at the age of 15 back to schools here. And they found that they were three years ahead in maths vis-a-vis their British contemporaries, but they were behind in essay writing and humanities, but way ahead in math. And probably quite behind and going to parties.

I think that's probably Okay, but you know what? Whereas you're not a mathematician but what you are is a genius historian who goes into great depth in research and talks to genius mathematicians so that's why this is a fascinating insight into the whole genesis of actually stuff

that we non-mathematicians take for granted. It was really, really interesting because once you stop doing maths at school in a sense you stop thinking about it and that's like you're married to a mathematician and go to mathematical conference. And having to look again at the history of this stuff and to understand it. And I had an absolutely fascinating time talking to a lot of people who study the history of mathematics and are specialists in it, including our great friend Marcus de Sotoy, who's done wonderful, absolutely wonderful programs on this sort of thing.

So he was very helpful. No, he's brilliant, Marcus. Marcus is fantastic. And often you'll meet people who, I had less and less these days, but you meet people who see the poetry in an equation and are able to express it. And that's a lot of what we're going to talk about today. But let's not blow the suspense. Let's carry on. So look, tell me, young man, what are we going to do? So we're doing the early developments in Indian mathematics.

And when we talk about Indian mathematics, it's something different, isn't it? So this section of the book, The Golden Road, we've previously talked on this podcast at different times about the different sections. We've talked about the way that Buddhism spread out of northern India, not only encompassing the whole of India, but going southwards, Sri Lanka and southeast to kind of Burma and Thailand, and then northwards to China, Japan, and Korea, so that Buddhism spreads right across Asia in about five or six hundred years and becomes the most widespread religion in Asia. Over half the world now lives in countries where Buddhism is now or once

was the dominant faith. We also looked at a different time about the section of the book, which talks about India's incredible trading relationship with the Roman world and the unexpected way that India was actually Rome's leading trading partner, and we looked at the way that Hinduism spread to Southeast Asia. So the final section in this book is about the way that Indian ideas most affected the West, which was through their mathematics, and most obviously in the development of the set of numbers that we in the West call Arabic numbers, because we got them from the Arabs, but in fact, we're meant by the Indians. And this is something that, of course, every Indian knows at school and is incredibly proud of, but no one.

and in the West knows about this contribution, which leads to the kind of, you know, the frustration of the kind of Sanjee Busker-style uncle saying Leonardo da Vinci, Indian, Jesus Christ, Indian, royal family, Indian. Because this is a major contribution to world civilization, the number system used around the world, the decimal system, the existence of zero. These are completely world-changing developments. And no one outside India knows that it all came out of great Indian philosophical ideas and thought. Well, I mean, that idea of a representation of nothing, you know, the zero,

the one mark on a paper to indicate nothing, zero, or a space in it. It was revolutionary, absolutely. It's like a grenade going off in mathematical thinking. And it is the thing, you're absolutely right that most Indian children are told that India invented the zero. And for ages, you don't understand. Yeah, okay. So what? All right. But it is very important. of you who are mathematicians out there, we'll know. It's one of the greatest abstractions of human thought and one of the most useful innovations in mathematics. And this is your book. I know this is your book and I've read it with enormous pleasure, but I have questions. So I mean, this is, you're talking about an outflow of information that is often then repackaged or disseminated and

people forget where it originated from. But is there also not a question of a melting pot of ideas? that because, you know, the Indian influence is spreading so far and wide, I mean, you talked about China most recently and the Far East and places like Thailand, but also, you know, the Greeks, Alexander the Great, his legions brought Indian scholars into direct contact with what they were doing with astronomy and their own sciences. And so you have this unique ganglion, if you like, of information, which is then developed into these sophisticated ideas. This is something that I think that many Indians may not be aware of. And certainly my interpretation from having really studied this hard over the last five years is that like all the great scientific advances anywhere in the world at any time in history, it's not some spectacular lightning strike and a completely innovative thought coming out of nowhere. It's people gathering together all the available information and taking it one step further. It's always you're on the shoulders of the giants who've been before you. And there's is true of the great development in Indian mathematics, which took place quite late on. I mean, Pythagoras was 500, 530 BC. And these Greek ideas get to India. They're known as the Yavona Sutras. And so do the ideas from ancient Persia and ancient Babylon, including the very first and earliest version of zero, which is just zero as a placeholder between an absence, a dot where there was nothing. but not understood yet as a number with active properties.

And so all these ideas are arriving in India, where they are mixing with the, if you like, first indigenous Indian mathematics, which people describe as Vedic mathematics, because they're connected with being able to observe the stars in order to correctly do the sacrifices laid down in the Vedic poems and hymns, which are often aligned with. with the stars. So you need to know about the movement of the stars and be able to make various complicated mathematical calculations in order to get your sacrifices right. Right. Okay. So gosh, I didn't realize it was sacrifice related till you told me. But on Vedic mathematics, just a quick little memory, I remember when I was a young journalist and I was sent, and I

went to an Indian news organization at that time, and I was sent to a school, and it was teaching Vedic mathematics. That was the way they decided they would teach mathematics. And you saw these tiny little, they were all white children. None of them were Indian. So like Indian children weren't doing this. It's like when you go to the Highlands of Scotland and everyone in the Gaelic classes from London. Right. But these really complicated, long divisions that they were doing in their heads using a system I didn't understand at all, which was, even when they explained it to me, the Vedic mathematics, was something so alien to my learning and understanding of maths, but they were much quicker at it than I was. So this has been around.

in India since, well, people dispute the dates of the Vedas, but some people say two and a half thousand, some people say a thousand BC. And all these different ideas are coming together. And it's during the rise of the Gupta's, the Gupta dynasty, who conquer and rule North India in the early centuries AD, that you see this great renaissance in all sorts of spheres of life. For example, Kalidasa, who sometimes called the Sanskrit Shakespeare, who writes great poems and plays like the Cloud Messenger and Shakuntala that are considered the great masterpieces of Sanskrit literature. They take place during the Gupta Golden Age. You get these gorgeous gold coins showing the Guptan monarchs ruling with these sort of rippling bodies. One is

playing a liar, another is on a horse, looking magnificent. They're some of the most beautiful coins ever made. And you get the Karmacetra, which is being compiled for the pleasure of the young men of Indian towns. So this is a period of sort of great learning, a period of flourishing the arts, but it's also a period of science and mathematics. Yeah, I mean, not many people may have heard of Vedic mathematics. I bet you've heard of the Kama Sutra there. And just to sort of anchor this in history, the Gupta reign was roughly between the early 4th to late 6th century, just to anchor these things in the continuum. Okay, so this is a time of great, would it be India's enlightenment? Would you go that far? So certainly there is,

a world of Indian nationalist historians that look on the Guptas as the great golden age of India. Here you have indigenous Hindu rulers who are building some of the very first Hindu temples in stone, although wooden ones have been around much earlier. They are particularly sacrificing to Lord Vishnu and the different avatars of Vishnu. And they're regarded by Indian nationalists as the epitome of Indian civilization when both the arts and the sciences were flourishing Indian trade to Southeast Asia was beginning, that it's a time of great riches symbolized by these gold coins. And what you get in terms of science and mathematics is great advances led by this figure called Ariabata. And Aryabata is someone, I mean, India's name satellites after him.

He's an incredibly important character. He lived in the city of Pataliputra, which is modern Patner in Behar. His dates are 476 to 550. And he has this wonderful little line of autobiography that he puts at the front of his work. And he says, by the grace of Brahma, I dive deep into the ocean of astronomical theories

true and false. And rescued the precious sunken jewel of true knowledge by the means of the boat of my own intellect. Well, that's beautiful. That's poetry. I mean, if you look at the commemorations, because there are now statues to Aria Butta. Aria means teacher, doesn't it? It's the honorific given to a learned person. And you see him, he's dressed as a monk.

So you can imagine, and these things are in stone now, but you can imagine a bare-chested, a saffron shawl or piece of cotton over his shoulder, and a dothia or a rap around his waist of saffron. He looks like a religious man. But it was in these religious establishments that the boundaries and frontiers of science and mathematics were being pushed. Absolutely. So Ari Butta comes up with various crucial ideas. He measures the circumference of the earth with incredible accuracy. He works out not only that the earth spins on its own axis, but he works out the distance between the earth and the moon. And he writes this extraordinary mathematical treatise in poetry. It's a dense, short poem that covers, and I just read the list of, things that covers, arithmetic, squares, cubes, square roots, cube roots, triangles, the properties of a circle, algebra, fractions, quadratic equations and signs, and it utilises a decimal system with place value, and it contains a very close approximation to the value of pi, 3.1416.

Which is amazing, amazing. I mean, it's extraordinary. And it also deals with spherical trigonometry, and he also writes these very complex lines about the movements of the planets, eclipses, and the exact length of the solar year to the accuracy of seven decimal points. And he writes this very nice line. He said, just as a man in a boat moving forward sees the stationary objects on the shore moving backwards, just so are the stationary stars seen by the people on the earth as moving to the west. And putting these different insights together, Aribata correctly calculates thousands of years before, you know, Copernicus and Galileo and all those

sort of characters, that the Earth rotates about its access daily and the apparent movement of the stars is a relative motion caused by the rotation of the Earth. And so all this stuff is sort of extraordinary. And it's contained in a single, dense poem. And the thing is, you know, to know the dance of the heavens at that time is very, very important. Not because people necessarily care where a star is, but they do believe that the stars govern what happens on Earth. So famines, plagues, all of these things, the whims of the stars are visited upon the heads of man. That's very much the thought. Exactly that. And this is a belief not just in India, but really across most of the world at this time. And so in the Arab world at the same time, you have a great

hunger to try and understand the stars because it's believed to rule our future. And so what you get in India is this science that they call Jotisa, which is both astronomy and astrology. So it's both at once the Daily Mail horoscope and it's NASA. And the two of which we think of was very different are put together. Can I just say you're describing one of my aunties, if only that were a newspaper, would be her favourite newspaper? Can I ask you this? I mean, would Arir Butter have been in the mountain of the sunrise observatory, which I've always been fascinated? I mean, you were talking about this is the era of proper rock edifices and science, and you'd get no better expression of that than the mountain of sunrise observatory. Tell us more about that and where it was.

And was that Aria Butta's hangout? Is that where he would have done his stuff? It's not, in fact, but it's not far away. So Aria Butta is in Pataliputra, which is near where the Buddha had his enlightenment at Bodhya in today's Uttar Pradesh. The mountain of the sunrise is Udegiri, which is near Bhopal and Sanchi in Madh. India-Bredash, so central India, south and west of where Ariabata was living. But what you see at Udeghiri are sight lines, water clocks, and various other signs that it was a major observatory that seems to use the science that Ariabata was coming up with. I mean, this is an enormous complex. What is still there? Can you still go there and what do you still see there?

It's about an hour outside Bhopal, which is the airport and the train station most people arrive in. And you pass the great Buddhist monastery and university in Stupa at Sanchi. And you head to Udeghiri. And the first thing you see is this wonderful relief of Varaha, the Boer incarnation of Vishnu. And he is shown in this massive sculpture with this sort of muscular body jumping out of the deluge. with the earth clinging to his tusks. So this is like the Indian version of the Noah's Ark story. The earth is under a deluge and it's rescued not by Noah in this case, but by Varaha. And Varaha, who is this incredibly powerful sculpture carved onto the rock face,

has got his feet on the snaky coils of a Naga king who has this sort of cobra's hood and he's sitting there with his hands together praying for mercy from Varaha. And then behind him is a now headless image of the monarch who created this astronomical complex, and that is Chandraghup to the second. And he is this heroic figure. You can see the kind of muscles again rippling across his frame. And even though he is headless now, you very much get this sense of authority and royal grandeur and dignity.

And this place is on the Tropic of Cancer. It's the probable original location of the famous unrusting iron pillar that's now in Meroli in Delhi. It's a big metal standard, which originally stood in the middle of this great observatory. And this is connected to a second observatory at a place called Ujjane. And that observatory, we know, was under the supervision of one of the followers of Ariabata, who's the other great Indian mathematical genius. You're talking Brahma Gupta, aren't you? Now, Brahma Gupta is a legend in India, a massive name.

He's a Rajasthani boy, isn't it, by origin? Exactly. He comes from a place that today is a place where all the Rajasanis go in the summer, Mount Abu, where all the princely states like Jaipur and Jobpur had their sort of summer retreats up on this mountain, which is so high that it's a completely different temperature from the plains below. And obviously, again, this is on the Tropic of California, and this is another place where there was a major early Indian observatory.

And Brahmagopter is reading Aria Butta's work, memorizing it and internalizing. And when he's only 30 in the year 6 to 8, he writes this extraordinary 25 chapter treatise on mathematics, which has a very complicated Sanskrit name, which can be translated, the opening of the universe, which is immediately recognized as a work of, extraordinary genius and subtlety. And then in his old age, Inoujain, as the master of the Royal Gupta Observatory, he writes a second book. But his great contribution, and this is something we touched on earlier, is to recognise that Zero, Sunya, the void, which is something that figures very prominently in Indian philosophy, that it's not an absence, it's a number with properties. That can do things. That can do things. That has an interesting role to play. Exactly. So it is, for example, the number you get when you subtract a number from itself. And there are a whole series of other rules that he lays out in this book. And as you said, it feels like a sort of something completely obvious that this should be zero there. But nobody thought of it before. And that's why it's sort of a detonation. That, you know, it's something that we've seen it. We've ignored it. It's been a placeholder for ages. But it actually has work to do. And if it can do this work, what else can it do?

Exactly. And it allows then you to do all manner of fancy tricks with decimal place value. So you can get zero, 10, 100, 100, 1,000, 10,000. You can use the binary system. You can also have negative numbers. Yes. Minus numbers once you've got zero. So all this is laid out by Bram Gupter, again, in a dense, complex poem. And these early Indian mathematical treatises are distinguished by this weird tick, if you like, that they didn't write in. sort of chapters of prose like a mathematical text would be today. Your kids will be learning. Like a theorem, pages of numbers and brackets. Exactly. Your husband has written wonderful books about Fermat's theorem, for example. And he didn't write it as a poem. He wrote it as a... No. I mean, that would be making your life very, very difficult. But they did. But the reason they did it was to aid memorizing. And all these kids, like the kids you saw in the Vedic school, would memorize these poems.

There's a word for it. It's called ratifying. Ractofying means just repeat and repeat and repeat until it's muscle memory. Yeah. So that's the way maths was taught. And these two books of Brahmagupta, building on the work of Aributta, brought forward both mathematics, astronomy, astrology,

to the highest peak. And this is the great golden age of Indian science. This is the point that India is way ahead of anywhere else in the world. It doesn't coming uniquely out of India. It's building on discoveries made elsewhere, but it is entirely Indian.

advance. So Callum, our producer, has just bussed me with a question. I don't know the answer, but you probably do. So before, you know, Bramagupta's work, could you not have had the number one million with all of its zeros? So I don't know whether the Romans had a letter which equated to a million in the same way that they had thousands and so on, C's and M's for hundreds and thousands. But what is the beauty of the Indian number system, once you've got zero in place, is that you can express any number up to infinity with just the nine symbols and zero. Lovely. That's a very neat, beautiful explanation. Can I just make one other observation? You know, you said he'd come to this realization at the age of 30. And many people will go,

oh, God, that's young. Actually, mathematics, all the rules are different. I hang out with mathematicians. And many of them say the best mathematicians have their ideas before they're 20 or when they're in their early 20s. And I went to a math symposium once with my husband, plus one. An unlikely plus one, I'll admit, to a math symposium. But it was Venice and it was pretty. So I went along and I was sort of talking to what these mathematicians. They were talking about these brilliant minds of these mathematicians who'd sort of gone into hiding or they'd become recluses. And they were describing mathematicians who were past their prime who were in their mid-30s.

Interesting. Is that amazing? Yeah. It's just an entirely different way of thinking about their human mind and what it's capable. So what we have now is the work of Aributta and the works of Brahmagpta, which very much build on that and take it forward. There's these two works, one of which is basically mathematical, and the second one, which is basically astronomical and astrological. And these books, at some point, get combined into a single complicated maths and astronomical text. And it is this that the Arabs over the Indus River want to get their hands on.

Well, join us after the break when we find out what those hands do when they get it. Welcome back. So just before the break, you were teasing us about how this raft of knowledge is floating its way towards the Arab lands. Now, tell us where does it land, who picks it up, and what do they do when they have it? So this was one of the most exciting bits of research that I did for the Golden Roads. And it's a bit that I think is not well known. People know that. the Arabs had this from India, but the exact method of how these mathematical innovations passed from one to the other has a history, and I was able to piece it all together. And I think it's one of the very first times it's been put into a tight, single chapter of a book. And it was one of the

bits I was most excited about. It's a great read. And anyone who knows anything about the Arab world in this period, and we're talking about the 700s, will know that there is why only one place, the very epicentre of learning is Baghdad at this time. Correct. And Baghdad, as people who know the subject are very familiar with, was a great circular city and was built very much on an Indian town plan. And I didn't know why that was until I started reading about this period. And the story takes us first to Afghanistan, to the town of Balk, where you can find the great Mahavihara or great Buddhist monastery of Nowbaha. And this monastery which was visited by our old friend and friend of the show, Shwan Zhang, the Chinese pilgrim monk who went to the University of Nulanda,

he went there and he praises the incredible library. But only 60 years after the visit of Shwan Zang, the great eruption of Islam takes place. And the Arabs famously in just two generations expand, massively out of the Hajas. They conquer both the Byzantines and the Persians. We've talked about that in the episode in the Persian series. They get as far as Spain on the West, and they get as far as the Indus on the east. But there's a little sort of handle that goes further east still when you go up to Central Asia. And Balk is literally the kind of the last place before China, the Arab armies have finally stopped. And the family of hereditary abbots of Nowbaha, who were known as the Pramuk, convert to Islam, and the young heir to the principality goes to the Middle East to a place

called Rassafa, where their names are arabicised to Barmak. But hang on a bit, that sounds a lot like Barmakid. That is the Barmakids who we've talked about. This is them. This is them. Right. Okay. This is the backstory to these people that we've met before in previous episodes. Yes. And just to remind people, when we've talked about them before, they were just a hugely influential Iranian family who, you know, were patrons of all sorts of things that made the region famous. So what seems to have happened was that these guys, because they were Buddhists, because they were Sanskrit literate, because they were from this great centre of learning, were themselves Prachrit literate and literate in higher Indian mathematics. One of their members, the original Barmak actually studied mathematics in the great universities of Kashmir, which are referred to in these texts and were major centres of learning at the time. Yeah, and just to remind you, I think we talked about this a long time ago, but the Barma Kids were so remarkable. They were so sort of venerated, especially their hospitality at the time, that you will even see mention of them in some of the stories of 1001 nights.

The Barma Kids are in there. Oh, they're at the centre. And one of the young bummer kids is Jafar, who is the great friend of Haramil Rashid. And then he makes it in. Well, you tell the story. It's Aladdin. He gets to evil Jafar with his crabby parrot. Exactly.

For reasons that are not entirely clear, Disney turned this guy who's rather heroic in the 1001 nights into this boo hiss baddie with this sort of English accent. But anyway, this family come to prominence because they have the. mathematical skills that others don't. And when one of their classmates from Rasafer leads an enormous rebellion against the ruling Umayyad dynasty of Damascus, the Barma kids are brought in, effectively as the Indian accountants to the CEO. And they do such an amazing job. And it's playing to stereotype, but it is actually true. These guys are so extraordinary with their mathematics that when the Abbasids defeat the Umayyads and need to build a new capital as an alternative to Damascus, it is the Barma kids who are chosen to build the new city of Baghdad. And they do so on an Indian

plan. It's this extraordinary city of half a million souls, a melting pot, not just of diverse Arab tribes, but also Persians, Turks, Africans, Armenians, Indians, Jews, Syrians, Slavs, and Byzantine Greeks. The city they plan is in all the travelogues of the time regarded as this sort of magnificent, dazzling place with palaces spread out along the banks of the Tigris, mosques, colleges, libraries, pleasure gardens. And here at the centre are the Barma Kids. And the first thing they do, once this city is built, is they send an embassy to India to get the works Brahmagpta. So Barakuta is the number one thing in their lending library. And we should say, I mean, Khalid I bin Barmak, who, who.

who is one of the main characters in this Barmaket dynasty, he is one of those, or he is the man who founds the House of Wisdom, this royal library, which is so extraordinary. It rivals Nalanda. It rivals that place that we've talked about in such detail with all of the scrolls of wisdom. It's the Caliph who in name certainly finds the House of Wisdom, but Carleton Barmak is the vizier who does it for him, if you like.

And the Barmakids are so close to the Abkhazirms. that they suckle each other's babies. They become teat brothers. Oh, you've told us that story. And I thought that was disgusting when you said it before. Oh, it's no, I'd rather like that idea. It's just the phrase teat brother. I can't. I just can't. Okay. All right. So he wants Brahmagupter's work, but wanting and getting a very different thing. So how does he actually get it into his new burgeoning library? So there's different stories. In one story, he sends a Jewish emissary to the astronomical observatory at Ujain, which is where Brahmagpta originally worked.

We don't know whether that yielded anything, and certainly when the book comes, it doesn't come from Ujahn directly. It comes from the court of Sindh. Now, Sindh is just over the Indus River, and the king there obviously had a great deal of interest in keeping the Arabs of Baghdad happy, because it's like having a superpower on your border.

It's like being, I suppose, Poland next to Russia. If you fall out, you're in trouble. The consequences could be bad. The consequences could be bad. So it is the king of Sindh, who sends this book, which, incidentally, the word given to the collected works of Brahmagpta and Ariabata in the Arabic is called the Great Sind Hind, which isn't its original title. But it seems to be a sort of a play on the word Sind and Hindustan.

But it was the single. most important text that ever got from India to the Arabs. And it comes not just with the book itself, but because it's so complex, and it's in all this sort of rhyming poetry, a team of Brahmin's come with the book from Ujjain, one of whom is called Kanaka the Indian. And he becomes a celebrated figure that reappears in histories of Islamic astrology for hundreds of years to come. And they keep his name. They don't change it. They don't Islamify as his name. and is still Kanaka? It's very important, actually, to recognise that in all Islamic literature of this period,

India is held up as the great place of mathematics and learning. There's no embarrassment, there's no sense that there's any anxiety about appropriating this from the Indians. They're very proud that they found a way of channeling this genius work to their own use. And the Caliph Mansour immediately gives this book and the delegation of Brahmins into the hand, of the court astrologer, who is somebody called Alfazari, and he begins the process of translating it. And Alphazari also becomes the first person in the Islamic world to build an astrolabe. And he begins writing complex astronomical poetry too. So an astrolabe, for those who maybe don't know, I'm not sure you all know, but it's

kind of a three-dimensional model of the spheres as they go around each other. I mean, is that the right way of putting it? That's exactly right. And the caliph, he summons Alfazari, and he says, you must translate this clearly in prose, quote, so that the Arabs might understand the motions of the planet. And that beautiful, but also hilarious. Can you just, can you leave out the poetry? Could you just put it in reasonable, readable prose, which is how it should have been written in the first place? Exactly. And so in the decades which follow, the Brahmah kids bring many, many more learned text. from India, particularly they're keen on Indian medicine. So the Ayrevedic system and the writings of

Characca are imported. The barma could set up an Indian hospital in Baghdad where Indian medicine is practiced and taught to the Arabs. And there's no sense of pride that, you know, they're too grand to reach out to their neighbours for the stuff. They recognise the achievements of the Indians. And they're very, very keen to bring it in. What would it have looked like? Because many, when you say library in Baghdad. Well, imagine a library that they've visited, that they've seen, you know, things on shelves, you know, things that anyone can walk in off the street with a library garden. The library, it's almost a place of worship. It is so important in the city. What would it have been in Baghdad to have gone to the library? Who could have gone? Well, we keep hearing about

the House of Wisdom, but we don't have a painting of it or a complete, you know, ground plan. So I can't answer that question. I don't think anyone else can either. We just have this a place that is known to be a college. It has effectively fellows and if you like Don's accredited to it. They live there. They work there. It's very similar, I think, to what the Library of Alexandria was in Egypt. So it's almost a little mini-citadel of learning. Exactly that. Now, what happens next is very important. The barma kids fall from grace in a spectacular fashion. Jafar, the baddie of Aladdin, is so close to Harun al-Rashid that there are even sort of gossip about the two of them being lovers or maybe Jafar has got something with the Caliph's sister. But whatever the particular rub was, at some point, the Caliph Harun al-Rashid,

who has been brought to power rather than his brother by the Barma Kids and whose tutor has been another of the Barma kids, whose best friend has been the son of the tutor, Jafar himself, he turns on Jafar. And there's a terrible moment. when he one night out of the blue gives the order that the Barmakid family is to be destroyed. Well, I mean, this sounds like one of those epic tragic ends to the, I'm going to use it now, the T-Twin story. But, I mean, you know, two people who were like brothers or more than brothers who then come to a terrible end. How does it happen? How does this end come? So we have actually an account of it.

And there's this poor bodyguard called Yasser, who is summer. to the caliph and told to kill Jafar. And of course, he's amazed and can't believe it's true. So he goes off to Jafar and he says, The Commander of the Faithful has ordered me to bring your head. And Jafar, who's just sort of settling down for a nice dinner and is not expecting anything like this, replies, The Commander of the Faithful likes to tease me.

This is no doubt one of his jokes. Oh, he thinks it's a joke. He thinks it's a joke. And by God, replied the officer, I have never seen him more serious. So the reply by Jafar is, well, if isn't a joke, then he must have been drunk. And Yasser has to say, no, by God, he seemed fully in possession of his reason. And from the prayers I've seen him before,

I can't believe he's actually drunk anything today. So at this point, the conversation gets chilly. And Jafar says, look, if there's anything I've ever done for you, please now remember that favour I've done for you. And the guard says, yes, I'm completely your service for anything that is not against the will of the commander of the faithful. So Jafar says, go back to him and tell him that you have carried out his order. If he shows regret, I shall owe you. my life and you may count on new favours from me. If on the other hand his decision remains constant, well, you must perform your duty. So he goes to see the caliph, who says, bring me the head at once, or yours at last shall fall. That's actually the translation. God. So, I mean, at that point,

Jafar knows this is no joke. This is not an outburst of, you know, can someone rid me of that troublesome priest? He's once best friend wants him dead. So Jafar has been listening to this. He's come to the caliph, he's hidden behind an awning or whatever, and has actually heard with his own ears what the caliph says. So he says, do your duty, you must cut my head, and he bandages his eyes, extends his neck, and he is beheaded. And then immediately the caliph gives the order cut off Yasser's head. I cannot bear the sight of the murderer of Jafar. Oh, for God's sake. It's really hard being around him, isn't it? Actually, he turns into quite a lunatic murderment, because he then orders the family of Jafar, his one-time best friend and Tide twin,

to be imprisoned and tortured and confiscates everything. He's a bit of a bastard. And his old tutor. And it all goes to the mother of Harun al-Rashid, who we dealt with during our episode on Al-Qa-Zarun. And Zubeda inherits all the estates of the barma kids. So all this stuff is wiped out. And the barma-kids are gone.

The barmecats are gone. But the manuscript. remain. Right. And there is a wonderful coda to this story. So 10 years pass, the viziers that follow are so anxious not to repeat the mistakes of the viziers that they direct the manuscript collectors and so on to look towards Greek learning. So this is the period that the House of Wisdom begins to fill with works of ancient Greek classics, which is how eventually they come back to the West, because it's through the Arab translations that we have these now lost classical text. then after about 10 years, a young man appears in Baghdad.

Well, he's from Kiva, which is in the area that the Persians and the Arabs call Khorasim. So when he arrives as a stranger in Baghdad, he's known as the man from Khorazim, Al Khorasmi. And Al Khorasmi finds all these Sanskrit texts that are lying now under a layer of dust in some forgotten shelf, and he realizes their importance. And he also realizes that the previous translations do not even begin to capture the complexity and the importance of the mathematics and astronomy contained there.

So Al-Karizmi gets down to work to produce a whole series of new translations. And he writes a book with this snappy title of the compendious book of completing and balancing by Hindu calculation. And because it's such a mouthful, Everyone just knows this by the nickname Al Jaba, which is the origin of our word algebra. Algebra.

Ketab means book, Algebra. Algebra. That's brilliant. Isn't that wonderful? And then even better, his name, Al-Qarizmi, becomes the basis of our word algorithm. Fantastic. Isn't that fantastic? It's a wonderful, isn't it?

I know you've told me that before, but I never tire of hearing it because it's great. And so this, it's Al-Qarizmi's version. of these Indian texts that is so clear and so simple that it spreads right through the Arabic world, right through Mesopotamia, Palestine, Egypt, through Libya, right through Morocco, on into Spain. And in the next episode, we'll learn about how finally these Indian numerals and the Indian number system moves from the Arab world to Italy. Can't wait. Listen, join us for the next episode to see how these ideas move from the edge of Christian Europe into the mainstream.

You know what if you can't wait. You know what to do. Join us. Join our club. So many of you are joining our club and we love it. You know, you get all sorts of things. You get our fabulous newsletter. You get early tickets to any events that we do, which sell out madly within hours. And you get bookless and all sorts of things. We spoil you. Just go to EmpirePodUK.com and you also get these mini-series all in one gulp. So if you can't wait and you don't like pacing yourself and why would you?

Empirpoduk.com is where you go. Join our club. Till the next time we meet. It's goodbye from me, Anita Arnan. And goodbye from me. William Thuripa.