You're Dead to Me - Medieval Science

Episode Date: September 24, 2021

There's a school of thought out there that, following the fall of the Roman Empire around Europe, there's a decline in knowledge, technologies, and economics. But is this true? Greg Jenner and his guests look at a range of discoveries spanning a thousand of years, widely known as the Medieval period. How was knowledge and scientific findings shared across a world with its countless languages and regions before the internet? Looking at essential scholars of the time like Ibn Al Hytham, the 'father of modern optics', and the evolution of compasses and maps, this episode picks up some of the weird and wonderful advancements of the period that we still use today - Medieval Science. Greg is joined by Dr Seb Falk, a historian of Medieval Science, an expert on astronomy and mathematics and the author of the book The Light Ages, which was voted Book of the Year 2020 by the The Times and The Telegraph. Alongside Dr Falk, we have the multi-award-winning comedian, writer, podcaster and filmmaker, Josie Long, who has alsp appeared on 8 Out Of 10 Cats, Have I Got News For You and House of Games.Research - Rosanna Evans Script- Emma Nagouse, Rosanna Evans and Gregg Jenner Project Manager - Siefe Miyo Edit Producer - Cornelius MendezThe Athletic production for BBC Radio 4

This is the BBC. This podcast is supported by advertising outside the UK. BBC Sounds. Music, radio, podcasts. Hello and welcome to You're Dead to Me, a BBC Radio 4 comedy podcast that takes history seriously. My name is Greg Jenner. I'm a public historian, author and broadcaster. I'm the chief nerd on the funny kids show, Horrible Histories. Today we are packing our sundials, star maps and astrolabes as we travel back many centuries to learn all about medieval science.

And to do that, I'm joined by two very special guests. In History Corner, he's a historian of medieval science and is an expert in the history of astronomy, navigation and mathematics. He teaches at the University of Cambridge, and his fascinating book, The Light Ages, was a Times and Telegraph Book of the Year in 2020. He's a BBC New Generation thinker. It's Dr Seb Falk.

Hello, Seb. Welcome to the show. Hiya. Thanks for having me. And in Comedy Corner, she's a multi-award winning comedian, writer, podcaster, broadcaster and filmmaker. She was the first woman to be nominated three times for an Edinburgh Comedy Award. You may have heard her on the radio or seen one of her many brilliant stand-up shows or caught her on one of her countless TV appearances on such things as 8 Out of 10 Cats, Have I Got News For You, House of Games. It's the marvellous Josie Long. Hello, Josie. How are you? Hi, I'm great. Thank you. I feel so good about myself after that intro.

You're properly smart. I'm six months pregnant at the moment and I play a lot of chess online with friends. And now none of them are my friends anymore because my brain is incapable of playing chess anymore. And my ranking has dived 100 points and I've lost 25 games in a row. So I feel intellectually really in need of reassurance. So thank you very much. Where do you stand on history? I did it for my A-levels. And I also was thrilled when I found out the topic of this Phil intellectually really in need of reassurance. So thank you very much. Where do you stand on history? I did it for my A-levels. And I also was thrilled when I found out the topic of this because we did a whole module in our history GCSE

on the history of medicine. And so I'm like, I am GCSE level ready for this podcast. A hundred percent. So what do you know? 100% So, what do you know? We begin, as ever, with a So What Do You Know? This is where I have a guess at what listeners at home might know about today's episode And medieval science, it's a tricky one

I reckon you all know what science is It's white coats and test tubes and Bunsen burners It's Dr Bruce Banner turning into a big green hulk But what about centuries ago? Perhaps you're picturing blood-sucking leeches, pointy plague masks neither of which actually were medieval at all, total myth. Or you might be thinking about flat earth theory, again myth. Or you might know your Monty Python and know that the best way to tell if a woman is a

witch is to see if she weighs the same as a duck. That is true. That is actually a hard science. But perhaps it's Harry Potter and the Philosopher's Stone, alchemy and astrology. But was medieval science more sophisticated than we think? Was it more everyday? And what did we get wrong about it?

Let's find out. Big question. Josie, in a sentence, how would you define what science is? It's the endeavour to try to understand the universe better. Hey, that's pretty good. Yeah, fantastic. Looking around, trying to figure out how everything works. It's very medieval.

Are we allowed to use the word science for the Middle Ages? Is science not a post-Renaissance, Enlightenment concept? Is it not modern? Yeah, the word science, as we understand it as a separate discipline, is a modern concept. But it comes from the Latin word scientia, which referred in the Middle Ages to any discipline that had a system, and that could include theology. But the rules that they followed were laid down by ancient philosophers like Aristotle and Plato. And so science, the study of nature, was part of philosophy. They had sciences like astronomy and mathematics and geometry, but in general, they could refer to them together as natural philosophy, the systematic study of nature. Natural philosophy sounds like the sort of slogan you get on the side

of a soap bottle. We believe in natural philosophy, and that's why all our soaps contain no sulphates. So when we're talking medieval, Josie, where would you put the start date and end date on medieval, roughly? Oh, God. So I was going to ask you guys, I was going to be like, can we just clarify here? Maybe it would end in about 1500?

That's spot on. And we'd say, what, 500 as a start point, maybe, Seb? Yeah, it's a nice thousand year period. Josie, when we say medieval what do you imagine? People in fields having really great holidays and or having to stamp in buckets of urine. I think it was heavily informed by a series that Tony Robinson did about 20 years ago. Yeah worst jobs in history Yeah, you were either having to be jumping up and down on leather in a bucket of urine or you're having a lovely feast and there was nothing in between.

That was life. It's King Arthur meeting the peasant, isn't it? Yes, exactly. Exactly. Oh, and of course, Monty Python and the Holy Grail. How do you know he's a king? He's not covered in shit. That's the Monty Python line, isn't it?

I sort of have vague ideas about what the Dark Ages were. You've used a dreaded word, Josie. Well, this is the thing. I know it's not real, but I still have these terms running around in my head. In terms of literature, I'm sort of thinking about Chaucer. He's an important part of this. But then I was thinking about

the earliest Old English literature that we did and how that fitted in. So, yeah, 500, yep, that's what I would have said too. You've already mentioned Aristotle and different Greek thinkers. So can we just have a very quick summary of what had been achieved before in terms of scientific thinking? Because it's not just the Greeks and Romans, right? It's the Egyptians and Mesopotamians. Yeah, as far back as 1800, 2000 BC, you've got Babylonians doing pretty advanced maths and astronomy, Egyptians too, and the Greeks pick up off that, the Romans as well.

But of course, we can't neglect what's happening in India, what's happening in China, and also Polynesian cultures, Mesoamerican cultures, you name it. It's a long and complex story. So what you're saying is we're idiots for trying to do this in a single podcast. I admire your ambition. So Josie used the dreaded Dark Ages and then very kindly apologised. Thank you, Josie. But I do know that it's a myth. I do. But it is a widely held trope, this idea of the Dark Ages, inverted commas,

that we get when the Roman Empire is said to collapse in the late 400s, and that we get the decline in knowledge, a decline in sophistication, decline in technologies. And there is something to that a bit. I mean, we do get a population collapse. There are some technologies that do fall out of use, right, Seb? Yeah, the Roman Empire collapses. Everything's falling apart politically, economically, and science depends on wealth, science depends on communication, on education. All of these things are linked to politics and economics. But of course, the Roman Empire doesn't completely fall because it continues in Eastern Europe, Byzantium, Constantinople. of Byzantium, Constantinople. You had your program on Justinian and Theodora. They're building Hagia Sophia, one of the greatest buildings of the first millennium AD. This is dependent on cutting-edge engineering and physics. Ideas, of course, pass to the Islamic world, and that creates a foundation for really impressive scientific development and exchange of ideas as well. If you mentioned the Islamic world, we get often what's described as a golden age of science.

Quite early on, there are a couple of really quite prominent caliphs who sponsor a huge amount of translation of ancient Greek and Roman texts, but also of doing new scholarship. Yeah, that translation movement from around about the 8th, 9th centuries is a really systematic effort by the caliphs in Baghdad. By the 8th century, the Islamic world stretches from Spain to India. So ancient Greek ideas get transmitted through Constantinople, often translated by the Christians of the Eastern Roman Empire into languages like Syriac, and then they're translated again into Arabic. And this gives amazing material for a whole range of Arabic-speaking scholars in the 9th century onwards. People like Al-Kindi,

who does incredible work in optics, Al-Khwarizmi, who lays the foundation for maths. We get the word algorithm from his name, Al-Khwarizmi, and a whole range of other scholars who become household names later in Europe, but in their own time are incredible contributors to the culture of the Islamic world. And we have a thing called the House of Wisdom. It's sort of been used quite a lot by historians, the library of knowledge, and in there there are mega nerds all beavering away. It's slight misnomer, isn't it, Seb? It's not quite true. It's one of those myths that never dies because it's really useful.

But the house of wisdom is mentioned in a few sources. But the word Beit al-Hikmah, the Arabic phrase, which is translated by house of wisdom, might just mean a library. It means a storehouse of knowledge. But what that is, whether this is kind of a research institute, whether this is a group of scholars, is a bit doubtful. I, as a historian and linguist, want to be pedantic and say, no, actually the beta-ligma is something different.

But since the stuff was going on anyway, people carry on using it because it stands for a vibe of the time. Well, also, it's really fun. It's exciting to think of something like that going on. And I suppose you just want it to be real. They have this really interesting thing that we don't have all we've got is troll farms you know it's not the same it'd be so good if we had houses of wisdom what would your research institute be called josie if you were put in charge of one

mine wouldn't be like the house of wisdom mine would be the house of some wisdom and a lot of self-driven relaxation. It's about work-life balance. There will be a swimming pool on every floor. If I'm allowed to build an institute, I think maybe investigating minor spats between YouTubers that I don't watch. So less House of Wisdom, more TikTok hype houses. That's your moral speed, really. No, this is too much.

No, it would be academic it wouldn't be it wouldn't be a hype house in itself it would be a very academic institute with up to two hours work done a day by some people up to on yes on whatever whims i had also if you were to investigate timekeeping you could call it the josie long never wrong ding dong institute what i'd be good about that is if there are any rows, I'd be like, this is par for the course. It's the Ding Dong Institute. Got to have a ding dong. It's what we do. One of my favourite people at this period in history, he's living in the Islamic world,

is Ibn al-Haytham, who I think we can call a visionary in the science of vision, right? He's a big deal in optics, which is a science of light and seeing the eyes, how it works, how it receives a signal. It is quite complicated, this stuff. I tried reading it and it slightly bamboozled me. So can you try and explain, Seb, what is it about Ibn al-Haytham that is so impressive in terms of what he figures out? Ibn al-Haytham, he does it all. He's born in Basra in what's now Iraq, around 965. He spent most of his life working in Cairo. And basically optics is one of those things that seems kind of simple to us today. But actually the idea of light as being this separate thing that moves around is quite a

counterintuitive one in some ways. So basically people had been asking questions for millennia, counterintuitive one in some ways. So basically, people had been asking questions for millennia, like, why can't I see with my eyes closed when I can hear perfectly well? I can hear what's behind me, but I can't see what's behind me. Why can't I see in the dark? Why do I need to turn the light on? Before Ibn al-Haytham, people answered those kinds of questions in two ways. You had the people that were really interested in eyes, who basically think, when I look at a building, something is coming out from that building and going into my eye. A little bit like smells. Horrible to think about it, but when you smell something bad, a little bit of that bad thing is actually going right up your nose, right? So why can't the same thing happen with eyes as well? The other view of optics

that was quite popular at the time was looking at it geometrically, saying, well, we know how mirrors work. Mirrors bounce things off in straight lines. We can understand how we see things by looking at the lines, looking at the angles. And that helps us really understand it mathematically. These geometrical theorists basically think about rays coming out of the eye, and as they come out of the eye, they expand. Like Superman. Yeah. And you somehow kind of capture what it is that you're seeing with these little rays that come out of the eye. So Eben El Haidim starts with these two basic schools that are

just completely incompatible. And he somehow manages to make them work together. And he basically creates a science of light. And also does experiments he writes things on a page and then he makes people look at them and then he gets his page and he's like okay so you can see this now what about if i turn it around here can you still see it now so ibn al-haytham he is incredibly important but he's also really influential because his ideas are copied and spread and there's a lot of interest in them in in europe well. What was he working as part of? Or is he just like a freelance vision guy? Like, was he part of an institution? Or was he somebody who just was a philosopher and brought his findings? That's a great question. It's a question that applies to all these people, right? It's like, where are they getting their money from? Even

Al-Haytham has a kind of really interesting story, because he first hit the big time when he moved to egypt in order to try and fix the problems that they had with flooding the nile right so famously the nile is both life giver and also bringer of chaos to egypt and he thought i can fix this can't be so hard can it and then he got to egypt the story goes he saw the impressive buildings of egypt and was like oh actually these people are cleverer than I've previously given them credit for. Maybe the Nile problem won't be such an easy one to fix. And the trouble was he had offered his services to the caliph, a chap called al-Hakim, who was famously brutal to anybody that didn't do a very good job. The most reliable sources seem to suggest that he had to go back to

al-Hakim and say, I promised I would fix all the water management problems of Egypt. I don't think I can manage that anymore. And so al-Hakim supposedly put him in charge of a government department instead, which sounds like a promotion. But I think in practice, actually, maybe was him being like, well, you've got to do something useful for me. So do this. And Ibn al-Haytham kind of saw which way the wind was blowing and was like, well, if I fail again, things are going to get a bit sticky for me. And the story goes, he had to pretend to be mad in order to get out of this government job. So he allegedly feigned mental illness for some number of years. And only when the caliph died was he able to kind of be released.

That was a lot bigger story than I thought you were going to give me. That had some real caper elements. It had some shocking elements. I didn't expect you to be like, well, of course, for 15 years of his life, he had to pretend that he was ill. Because, like, wow.

Ibn al-Haytham, very busy man. We think he writes 92 different books, which is very prolific. One of them, we only have the title. We don't know what's in it, but the title is brilliant. Ibn al-Haytham, very busy man. We think he writes 92 different books, which is very prolific. One of them, we only have the title. We don't know what's in it, but the title is brilliant. I love it. The title is something like the influence of music upon the souls of animals, which I like to imagine. Therefore, he spent his time just playing flute to a camel saying, how do you feel? Do you feel relaxed? Do you feel cheerful? Do you want to go for a walk? So, Josie, science time. Relaxed? Do you feel cheerful? Do you want to go for a walk?

So, Josie, science time. What would be your scientific hypothesis? Do you reckon you can hype up a hamster by playing it some Ariana Grande tunes? Oh, 100%. I think the more the better. And I feel like my hypothesis is that there's no beast that wouldn't be thrilled by Ariana Grande. She's a good person. She's a comrade. And if you hear that music, the response of the beast will be akin to thank you next that's what it will be in the animal's language i think it's pretty fail-safe i can't imagine even a fox or a whale or other animals i can't even imagine a spider

disliking it it must have been such a thrilling time to have so many fields where you could really feel like you were making world-changing discoveries in that way and like obviously then you can people now can look back and be like oh i thought it was lasers whatever but like you know how wonderful to be able to go to the people you work with and the people you admire and be like, I believe I have solved this gigantic problem. Yeah, and anyone can do it. A lot of this knowledge in the Islamic world then percolates back into Europe. Of course, the Crusades means you've got obviously horrific violence, but there is still exchange and interaction. You have the Silk Roads and ideas coming from China, but there's also stuff coming in from India, right? So our Arabic numerals, 1, 2, 3, 4, 5, we call them Arabic

numerals because they came to us through the Arabic world, but they're actually Indian, aren't they? Yeah, that's right. So Al-Khwarizmi, who I mentioned as coming from Central Asia before, he seems to have been responsible for bringing what he thought of as Hindu numerals or Indo numerals, Indian numerals, to Baghdad. And then they make it from there to Europe in the 12th century. But the Europeans, the Latin Christians, are aware at the time that they have come from India. And this is the 12th century in Europe, when Europe has its own translation movement to rival the one in the 8th and 9th centuries in the Islamic world. The universities are founded in Italy and in France and in England. And those kind of two movements together,

backed up by economic growth and rise in cities, basically means you've got suddenly everybody starts to look outwards and think, well, you know, I can find out stuff that has not previously been available to me before. So you get this guy, for example, Gerard of Cremona in Italy, who goes to Spain to try and find the Almagest, this book by Ptolemy, the ancient Greek astronomer. And he finds it in Arabic and he learns Arabic in order to be able to read this incredibly difficult. I mean, like I read it in English and I can't understand half of it. So this guy learning a completely new foreign language in the Middle Ages without Google Translate in order to be able to study this one book. in Toledo in Spain translates a whole bunch of other books as well by ancient Greeks, by Muslims, books on astronomy, philosophy, medicine, alchemy, you name it. He's doing all these things. And that's kind of in the spirit of the movement, really. But imagine if he went to all that effort and then he didn't even like the book.

Not for me. The ending is a bit derivative. Yeah, like, that was what it was good it's so exciting to think that that back then it was like an individual that had such an effect on so many subsequent people's abilities to learn and to engage with the world the weird thing i suppose that some of our listeners might be in their heads going well hang on a second greg mentioned the crusades where everyone hates each other and horrific, violent, holy wars between the Christian church and Islam. And yet here we have Christians, Europeans, learning the enemy's language, reading their science, reading their ideas, taking them home, adopting them.

So I suppose the obvious question is, well, was that okay? Was that accepted? Did the church, if we think of the church as some sort of top-down singular body, was that fine? Are these ideas, are they not dangerous? So some of the ideas are potentially dangerous, like Aristotle's idea that the universe is eternal obviously conflicts with a pretty basic premise of Christianity that the universe was created. That was a problem in Islam too. Other ideas, if they work, it doesn't matter where they come from. And there was a really established doctrine in Christianity, goes back to the Bible, that the Jews, when they fled from persecution in Egypt,

nicked a whole bunch of Egyptian gold. They basically took whatever they could carry and ran off across the Red Sea. And that was okay because they were taking it from the oppressors and they were putting it to better use. It's punching up, that's punching up. Exactly. So theologians like St Augustine come along and say, well, you can do the same with knowledge, right? If somebody who is an infidel and wrong about faith happens to be right about science, well, you can take their knowledge and you can put it to good use. The church is sponsoring science because they want to find out about God. Then what better way to do it than studying creation, studying the evidence that God has left for his intentions for mankind? So basically, there's a real kind of solid logic behind doing science. And there's no reason why the church would want to stop people doing that, basically.

There's no reason why the church would want to stop people doing that, basically. That's where we then get some fascinating people who are both scientific and religious. Josie, have you ever heard of Hildegard of Bingen? No, and I feel so sad not to. Please tell me more. She's said, I mean, how would we describe her? I mean, I suppose an abbess. She's quite a medical writer, isn't she? But she's also got other ideas that are more scientific.

How would you summarise some of her general output? Hildegard of Bingen is probably most famous today as a composer. So people still sing the music that she wrote. But she's, as you say, Greg, she's an abbess. She's living in the sort of first three quarters of the 12th century. She is interested in everything. So as an abbess, her job is to look after not only the people in her monastery, but also the people around. So she looks at medicine, she's interested in herbal cures, but she's also deeply religious and she's a visionary. And she has these incredible visions, these views of the universe as created by God. But she's also a very practical thinker in terms of medical ideas and looking after people. And she does music as well, which sounds like a kind of a weird combination. But

actually, for a lot of scholars in the Middle Ages, it was all part of the same kinds of science, because music was a science of harmony. Harmony is based on ratios. And so studying arithmetic helps you with music. Stud studying arithmetic helps you with music. Studying geometry helps you with astronomy. All of these sciences are connected. So for somebody like Hildegard, it makes perfect sense. Well, I was going to say, universities love it if you've got a good mix as well, don't they? They don't want you just to be... On your UCAS form.

Yeah, they like to have a bit of, you know... So it wouldn't have hindered it. Science and faith basically as intertwined as Bennifer, which obviously have a bit of, you know, so it wouldn't have hindered it. Science and faith basically as intertwined as Bennifer, which obviously is a cultural reference. Well, not last. Women in STEM is an ongoing discussion these days. STEM, if you don't know, stands for science, technology, engineering and maths. Or if we're adding medicine in, I guess it's STEM. But I mean, there are women in science in the medieval world, right, Seb? I mean,

I don't know if they're necessarily formally in positions of power. I mean, Josie made the idea of freelance scientists earlier, which I think is rather charming. But there are women doing practical and theoretical science in the Middle Ages, right? Yeah, I mean, Josie hit upon it earlier with the question of who's paying for this. It was much harder for women to make a living doing any of this or have any kind of official position, because after the universities were founded in the 12th century and into the 13th century, it was only men that could go to university. Formal professions, formal education, and increasingly you get professionally trained physicians, doctors, who again, almost entirely men. But women could practice in lots of really interesting and

important ways. And there are other examples apart from Hildegard. So you've got Herod of Hohenburg in Alsace, the kind of French-German border, who writes this incredible book of education, liberal arts, for the nuns in her abbey, including how to calculate the date of Easter, and how to do all of the different sciences. Other parts of the world too, there's a famous astrolabe maker called Bint al-Ijli. But the part of STEM that women are most involved in is undoubtedly the M, it's medicine. Because basically, for all of the Middle Ages, frankly, if you want to get medical treatment and you don't have the money to pay for a licensed

physician which as i said was always a man you would go to generally a wise woman who would probably do as good a job as a professional expensive doctor and crucially the one part of medicine that women were really involved in of course was childbirth a woman who's giving birth would normally be attended by a midwife. So we've got a sense then that science is happening in a few places. It's happening in monasteries and nunneries and in universities, and it's happening under house arrest for certain scholars who have to pretend that they are not very well. Another person we should just mention who is not particularly important, but it's a fun story, frankly, Josie. I like a fun story. So have you ever heard of Elmer of Malmesbury? No, I haven't. But what a name. So Elmer of Malmesbury was a monk at the Abbey there in Malmesbury about a thousand years ago,

give or take. And he wasn't doing research in the library. He was doing something a bit more dangerous. Do you want to have a guess what he was up to and clues in the up? Was he jumping off of things to test velocity beautifully guessed uh jumping off of things to see if he could fly uh as far as we can tell seb he strapped on a pair of wings on his wrists i think on his arms and on a pair on his on his legs and he leapt off the church tower listen he could have at least done it off a pier, you know? Give yourself a fight and jump. There aren't many piers in Malmesbury, it's quite a long way in there.

This is why it shouldn't have been up there. Do you know what I'd like to guess? That he somehow fluked it and created something akin to a glider and had a relatively soft landing. A bit shorter than that but he didn't just plummet he sort of did a bit of a buzz light year he did falling with style

he flew for a while uh smashed into the ground and broke his legs in fairness and hobbled for the rest of his life but he survived so arguably that is flying, sort of. But he's the only person of that time who'd done that extreme sport. And he must have felt very lonely because he'd be like, you don't understand the buzz I got from jumping off the abbey. And no one does, you know. He'll be like someone who's kind of had a really great experience on holiday. Yes, he hobbled for the rest of his life. Unfortunately, he was seriously hurt, but he did survive.

Another brother, not a monk, but a brother, who was doing some dangerous research was Roger Bacon. And he's considerably more important in the history of medieval science than Elmer the Dangerously Leaping Off Buildings of Malmesbury. So Bacon was a Franciscan friar in the mid-1200s. He's doing work on optics. He's also our earliest source of knowledge really on European gunpowder, which suggests, Seb, there's a route into Chinese science because gunpowder is a Chinese invention. Yeah, Bacon's taking advantage of these

Franciscan networks. So these new orders like the Franciscans and the Dominicans are the basically international religious networks of their day. And they are transmitting ideas. There was a guy called William of Rubruck who had travelled to the Far East and found out about things like gunpowder. Roger Bacon went and studied in Paris. Travelling abroad, studying in different countries, it's not a new thing. And particularly because they were all speaking Latin. So somebody like Bacon could go to Paris and speak in Latin to scholars from Germany, to scholars from Italy, and exchange ideas. Bacon himself is really worried about the Mongol invasion, about the expansion of the Islamic world. He thinks something like gunpowder might be the solution to their problems. Also, he thinks that he might be able to use burning mirrors to try and direct the energy of the sun towards opposing armies so he's into all kinds

of interesting ideas he's again doing experiments himself he's putting things to the test josie do you remember any uh fun science experiments from school oh i do remember we had a substitute chemistry teacher who we found out had been teaching in prisons who taught us how to make contact explosives blimey the man did not teach long at our school, but it was an incredible lesson. I hated chemistry and I listened more in that lesson than any other year, yeah. I guess he'd got fired from prisons for that

and he absolutely got fired from our school, but yeah, that was a great day. I suppose the most famous thing about Bacon, he's often said to be someone who falls foul of the church and like ibn al-haytham ends up under house arrest are we getting our myth busting cannon out here seb bacon he thought that there were lots of really interesting things going on in nature so he was keen on experimenting but to call him like an experimental scientist will be way over the top because he's not experimenting in any kind of systematic way he's just trying to shit out and seeing what flies so he's interested but he also is really blunt about criticizing

people who he thinks are doing it wrong he says oh albertus magnus albert the great i mean it's the clues in the name he's a genius this guy he comes from germany he goes to paris roger bacon is having none of it he's like this guy this guy knows nothing. He's not properly trained. So Roger Bacon doesn't mind stirring the pot a little bit. And so it's possible that he got into trouble. But the only evidence that he was arrested comes from at least 80 years after the events were supposed to happen. He might have lived to about 80. And in the later years of his life, we don't really know where he was or what he was doing. So it's possibly true, but the evidence is a bit sketchy. He might just retire, you know, just be doing his garden. And one of his big interests was alchemy.

Josie, what do you know about alchemy? Is alchemy specifically about turning things into gold? Or is it just more magic in the wider sense that is a fabulous question oh thanks you have hit on the historiography of the discipline right there oh my god i'm the elmer of malmsbury of this podcast i've done very well absolutely you took a leap of faith and you landed. So Seb, is alchemy gold and elixirs of life? Or is it also transmutational chemistry and magic and the heavens? Yes. So basically, alchemy is about uncovering the hidden ways that the world works.

And because it's about uncovering the hidden ways that the world works, people are really secretive about it. And so you get all of these really very vague treatises that are like, here are some secrets of alchemy, but I'm going to write them in this really obscure way because I don't want anybody else to know my secrets. Or if you want to be a sceptical, you could be like, well, they hadn't actually really discovered anything at all

and they were just trying to make it sound like they knew more than they did. But these alchemical treatises are really hard to interpret because there's these different layers to them so there is the like i can purify metals i can make gold but there's also i can spiritually purify i can understand the cosmos but the basic concept is that everything is connected right so each planet is associated with a metal, and with the powers of the planets, you could purify metals. And they also wanted to extend their lives. You've got this idea about the elixir of life, or to heighten the senses. So alchemy can do a huge amount.

But the key point that it gives us, alchemy is the forerunner of modern chemistry, because they develop a huge suite of techniques. They're distilling, they're boiling, they're cooling, they're filtering, they're heating, they're mixing, they're doing all these things. And they're thinking about substances in kind of creative ways. So in order to distill something, you need to be quite precise about the temperature that it's at. So they are developing new experimental apparatus. And so it creates and develops new techniques which go into later chemistry so they're basically wizards but they're nerdy they've smoked a lot of pot and they're sort of having big sort of like oh man it's all connected i mean one of the things that comes out as a

byproduct of alchemy really in the islamic world is alcohol distillated spirits josie if you were to have a tipple of i don't't know, whiskey or whatever, actually that history goes back to the search for the elixir of life. And alcohol is from an Arabic word, al-kul, and it was known as the quintessence, the fifth element, believed to preserve long life. I love the fact that there's been two words on this podcast already. I didn't even think that I didn't know the origin of. And the fact that the al part comes from the Islamic word

and not from a French or whatever. And being like, of course, owl, a thing. That's how the word would have started. What a joy to find these things out. Because I was like, algorithm, sure. Don't need to investigate that word. It's great. One famous alchemist, Josie, who we probably don't think was real, Bernard Tre trevisan italian chap supposedly probably a fictional

punch line he was said to be squandering his family wealth on trying to make gold out of which two ingredients do you think well i would hope one of them was straw because of all the fairy tales and lead one of them's got to be lead lead is a good guess think more gross oh no i feel like there was a lot of people using the urine of horses for things would it be that you're not far off other end of the horse it's feces and eggs supposedly these are 16th century stories about this guy and we think they might be satire they might be taking the mick out of alchemists as being silly people who waste their money on stuff so there's a sense here that said that perhaps there's also a backlash against alchemy there are people mocking it and saying these guys over here they're in their

wizard castles chucking poo around you've got to give it a try and horse urine was a key ingredient in the first contraceptive pills right only about 50 years ago so uh it's not as out there as you might think so bernard trevisan possibly was trying to polish a turd, if he was real. So Seb, you are a historian of navigation and cartography and astronomy. It's a myth that people in the medieval world thought the Earth was flat. We know the Greeks knew the world was a sphere. Josie, how would you, as an ancient Greek, figure out the world was round? Assuming you can't get in a boat and sail around the whole thing.

Oh, but you could watch someone going off in a boat and be like, they've gone. Yeah. They've gone. And then you'd be like, well, two options here. They've fallen off the edge of the world or something going on. You'd watch the sun in the sky. Seb is nodding.

I feel like those two would be a good start. It's to do with horizons. I think Josie's hit quite a lot of nails on the head there, Seb. I mean, can you give us a very quick introduction to the science of how do you figure out the world is not flat? Most common proofs are, first of all, to look at the sun and the stars. So you can see that the sun rises and gets up to different heights depending on where you are at different places. And of course, time zones. Aristotle had some good ideas.

You can look at the shape of the Earth on the Moon during an eclipse. Probably the most common explanation, when a ship sails away, a person at the top of the mast can see harbour when people on deck have already lost sight of it. So there are lots of different ways that you can prove it. This proves really, Zeb, that people are continuing ancient knowledge and they're refining it. How does geography work or even cartography in terms of navigation? People are travelling the world, they're trading, they're going to wars. How do they get around? How do they communicate to each other where they've been?

There's two kinds, really. There's the math stuff that I've just been talking about. You can work out the size of the Earth by looking at the sun and the stars. You can work out latitude and longitude. You can kind of more or less draw a grid and kind of imagine the size of the earth and roughly where things are. And then there's the local traveller's stuff, the practical knowledge that you need. I don't need to know what the latitude of London is to come down to London. I just start walking in roughly the right direction and a couple of days I'll end up there. And that is more or less how people travel in the Middle Ages. Josie, I mean, you're a touring comedian, right? You're often on the road. So how do you

navigate? Yeah, pretty much the same. It's why I have long gaps in between gigs. I'm like, wow, if I point myself in the direction of the North Star, it's going to take me 12 days to walk it, but it will be worth it. In terms of mapping, Seb, do we have compass yet? The compass comes into Europe in about the 12th century. For a long time, they've understood about magnets and lodestones and the compass pointing towards north. But then people kind of experiment with it

in really interesting ways. There's guys who try and use it to come up with perpetual motion machines, for example. But people do increasingly use it for navigation. So before the 12th, 13th century, there's no need really to draw up complex maps because people just ply the same waterways they always have. And then as people go further afield, they say, you know, when I get to this harbour, if I'm going on crusade or I'm going on pilgrimage, when I get to this harbour, where's a safe place to anchor? And so, you know, they start off with these little harbour plans that show, you know,

which bit of a harbour has the rocks and which bit of a harbour has the safe anchorage. And then it just kind of expands from there. Yeah, the mermaids, yeah. Make sure you don't drop your anchor on a mermaid. They won't thank you for that. The compass roses and the rum lines go together. A rum line is just a kind of straight line on the chart, sort of shortest distance from A to B. So they get progressively more complicated. But there aren't, at that time, grid lines of latitude and longitude. That's what's kind of really interesting. It's like

they understood latitude and longitude, they just didn't think it was worth putting them on a map. They were used for the sky. Josie, do you want to see a medieval map? Oh yeah, definitely. Okay. This is called the Tabula Rogeriana, Roger's map, named after King Roger. It was made by an Arab scholar called Al-Idrisi in the 1150s. This version is a 15th century copy later on, so it's a bit later. Do you want to describe for us what you can see?

I suppose it almost is like the land and the sea are inverted in it, because it feels like there's more land than sea on it. because it feels like there's more land than sea on it. It's all in a circle, but it's tilted. So you feel like it's got some 3D spherical style to it. It's got, I don't even know what this like gilded rope, oh, mountains. Okay. All right.

So a lot of it is about mountains and where they are. And it reminds me of when I try and draw a sketch map for a friend of mine. And I'm like, well, and then up there, that's where that cafe is that you might like. And over there is that. It's sort of not accurate. And where do you think Europe is on this map? The far left at the top. So like one of those will be the Alps. Is that wrong? That's how we think of maps, oh turn it upside down turn it upside down so north is in the south south is north in terms of how we look at maps so there we go that's one lovely medieval map uh now on to a second lovely medieval map this is called the map of mundi you may have seen it before josie it's available to

see in hereford cathedral it is a very beautiful map from about 1300, I think, give or take. We've got an interactive version. If listeners want to go and have a look at it themselves, they can. They can type in Map of Mundi and Hereford Cathedral's website will show you it. Again, the world here is shown as a sort of sphere, right, Seb? It's sort of circular. The unusual thing, I guess, for us is that Jerusalem is right in the centre. That's the, obviously, key city for religious christians in hereford josie where do you reckon london is or

even hereford is on this map i'd love it if they just put it next door it's like oh we're very important as you can see i mean i'm still gonna go top left you're wrong top left is where the garden of eden is right in the top uh garden of eden's on this map by the way we've also got various creatures and monsters we've got dog-headed men uh we've got the golden fleece of jason and the argonauts but hereford and london are in the very very bottom left instead of having south at the top like in the last map had we've got east at the top it's an enormous map it's like a double bed sheet. It's about five foot square, and it was made from an entire cow skin. And it's divided into basically Europe at the bottom left, Africa at the bottom right, and Asia in the top half. I've just had such an obvious and silly realisation that the people making these

maps didn't know that the Americas existed existed i was like yeah and america is like oh yeah they don't know josie how are you with astrology are you into star signs i really feel like it's something that makes me feel old because i know that gen z people love star signs and believe them and care about them fashion i know. And it, to me, is something that I can't quite accept because when I was growing up, you might read a star sign in a magazine for a bit of a laugh, but it did not factor in my life at all beyond that and kind of mystic Meg. In the Middle Ages, astrology is predictive. It is sort of magical, sort of scientific. What are the differences between astronomy and astrology in the medieval period?

Astrology is like the practical implementation of astronomy, right? So it's a serious science. It's not just Scorpio, Virgo, Libra stuff is your sun sign, right? That's where the sun was among the stars on the day you were born. But there's way more to it than that. And everybody in the Middle Ages pretty much believed the general concept that the planets affected what happens down here on Earth. And it's kind of logical in a way. The sun heats up the Earth. The moon clearly affects the tides. So why can't Jupiter affect things as well? They only knew about the planets

as far out as Saturn, but they were well aware that they were planets. They looked up at the stars and they saw that there were some stars that moved in an irregular way against the general background of fixed stars, as they were known. And so those wandering stars are called planets. And as they wandered, they kind of cast different influences depending on where they were in relation to each other and where they were in relation to the constellations. Planets each have links with elements. The Earth is made of elements. Even today, we talk about the weather as the elements. And so it's bound to affect the weather. Humans are made of matter. Humans are made of elements. So if it can affect the weather, it can also affect your health. It's a short step from astrology affects the cosmos to actually people's behaviour, people's actions can be foretold in the stars.

Josie, you've already mentioned Geoffrey Chaucer. Have you read The Miller's Tale in The Canterbury Tales? Yes, but maybe 21 years ago. The Miller's Tale is about a smug, clever young student who's got a landlord who's married a very hot woman called Alison. The student figures that the landlord's a bit thick and that he could probably seduce Alison. So basically what he does is he terrifies the landlord into saying that the great flood is coming back. God is going to flood the earth again a second time.

And he tells him, go and build a little ark, a little tub boat and hide in it. And I'll hide in mine and Alison will hide in hers. And if we stay very, very quiet, then God will spare us. And in the morning, the waters will recede and we can all go back to living our normal life. And so the landlord, who's a bit thick, goes and builds his tubboat and hides in it. And meanwhile, of course, Alison and the student have some rumpy pumpy time.

So it's a really funny story. I mean, it's a classic Chaucer story. It's cheeky, it's naughty, it's a bit rude, it's a bit sexy. But actually, the student has used an astrolabe to fool the landlord. He's basically conned him with science. He's using science to get his end of way. But more than that, Geoffrey Chaucer actually wrote an actual book, an actual scientific treatise on how astrolabes work. So Chaucer was really interested in the science and put it into his stories. What is an astrolabe? I'm so glad you asked. Well! Well, here is... I'm holding up an astrolabe. It's like a brass disc.

It sort of just about fits into the palm of my hand. And it's got various moving parts. It's got a kind of ruler that turns over the centre of this disc. And it's got a wheel in it. And it's a little bit like the alethiometer from His Dark Materials. A bit like a compass. But it's the medieval smartphone. It's your multifunctional gadget.

You can tell the time with it. You can work out which way is north, when the sun's going to rise, the height of a building, but also it's pretty and it looks cool. So in that sense, it's a bit like a smartphone because it's a status symbol as well. But Chaucer wrote this book called, depending on what you think, he may have called it Bread and Milk for Children, meaning it's really easy, but he addressed it directly to Lewis, his 10-year-old son. So it's really like any 10-year-old can understand an astrolabe. Chaucer gives, I think, about 45 different uses for it, but some people claim that they knew a thousand. It's like a BuzzFeed article, 45 uses for your astrolabe.

I must say I'm slightly disappointed because in my head, I thought it was something that you would set it running and it would spin I don't know why so I mean not to do it down because it is beautiful and it must have been really stunning at the time as well but I thought it might be something a bit more clockwork that you set into motion honestly you're the first person I've ever met who hasn't been impressed by this I'll get a bigger by this. I'll get a bigger one. All right. I'll get a bigger one. How about this? Does this impress you now? Are you not entertained? It's a big astrolabe.

Let's be real. But can you spin it on a string? You can't. You're thinking of a yo-yo, Josie. Look, it's got a little bird on it. Can you see? It is a very beautiful thing, Seb. Josie, you've mentioned clockwork there.

Clockwork is a medieval technology, right? It's automata, it's cogs, it's bits and bobs that once you set them in motion, they're self-propelling, they're self-driving. We know that church bell towers had clocks put into them. And clocks go clockwise because astrolabes go clockwise. So a clock face is kind of modelled on an astrolabe. In terms of the great inventors of automata, there is a guy called Al-Jazari in the 1200s. There's a really long history of automata, like clockwork stuff. The ancient Greeks did some.

It was massive in China, where a lot of them were water-powered. The Islamic world too. As you said, there's this guy called Al-Jazari who lived at the end of the 12th century, who had all kinds of incredible, complicated, basically robots, all moving parts with fluttering birds and people moving around and water that drains out and gets refilled. And what makes clocks a really important invention is that they have an escapement that basically regulates the time. So they tell constantly the same amount of time. Yeah, it's amazing stuff. And clocks are super important in the 1200s.

They go into these bell towers in Italian cities and so on. And they regulate economies as well. They really contribute to the growth of trade. They help turn these cities into economic powerhouses. And actually, the word clock means bell in Latin, clocka. So actually, those bell towers are really important. Just very quickly, we were hoping to squeeze some Chinese history into this episode as well, but we haven't really got the time. So let's just do the very big headlines.

Sep, there are four great technologies that come out of medieval and ancient China. One of them, of course, is gunpowder. What are the other three? Yeah, we already mentioned the compass, but the really big ones are paper and printing, which I think the big thing about Chinese history of science is it's all almost entirely very practically focused. It's like, how can we rule a country better? And so it's paper and printing enables their phenomenal bureaucracy to function properly. Josie, which of these many, many things that you've heard about

would you like to study most at the Josie Long Never Wrong Ding Dong Institute? I'd be very into people making some clockwork machinery on my time and my funding. Excellent. Also, yeah, some alchemy would be great. Inventing another sort of elixir of life would be good, yeah. I mean, alcohol is technically the elixir of life, the quintessence. So technically speaking, a bottle of whiskey is that listen these things need to be really studied and proved so you can be a hundred percent safe the nuance window lovely and with that it's time now for the nuance window this is where we allow our expert two

minutes to say anything at all that we need to hear about today's episode. And what's going under the microscope today, Seb? I am going to talk about ditching Aristotle. So in 1277, the Bishop of Paris, who was working with a bunch of theologians, condemned 219 false propositions, which he said were being taught by philosophers at Paris University. And these propositions ranged from theologians talk nonsense and philosophy is the best to the universe is eternal and a vacuum cannot exist. And the Bishop of Paris said, you can't teach any of those ideas. And that sounds like a big clamp down on academic freedom. And indeed it was. But surprisingly, it may have actually accelerated the development of science, because many of those ideas were associated with Aristotle,

the ancient Greek philosopher, and he was so good that medieval scholars often didn't look beyond reading his works. Medieval scholarship was all about building on previous people's ideas, not knocking them down. But the 1277 condemnations forced medieval scholars to think outside their Aristotelian box. What does all this tell us? Well, if you take away one thing from all this, it's to have alarm bells ringing in your ears if you hear people call Roger Bacon or Ibn al-Haytham or even Newton a scientist. Because that word gives us too clear a picture of a modern professional working with specialised equipment in a purpose-built space. And motivations and methods of science have changed enormously over time. So the theologians in 1277 weren't saying

a vacuum had to exist. They were saying God could make one if he felt like it. By trying to protect the power of God, they inadvertently promoted science. On the other hand, Newton wrote that the purpose of his science, natural philosophy, was to tell us about God. In many ways, he was more medieval than modern. Now it's easy for us today to assume our way of looking at the world is the right way, just like medieval people did, but future generations might not agree with us. Our attitudes towards scientific and technological progress, which prioritise human comfort above all, have certainly harmed other living things around us, and there are so many other questions we haven't answered. So we shouldn't belittle people who don't think like we do, who have different

ideas of progress, whether they lived a hundred years ago, or a thousand years ago, or are living today. Just as those 13th century theologians who were trying to take the philosophers down a peg or two may have released them from their mind-forged manacles, so appreciating different ways of looking at the world can free us from the limitations we put on ourselves. Amazing. Well, thank you so much. So what do you know now? It's now time for the So What Do You Know Now? This is a quickfire quiz for Josie to see how much she has learned. You're a big fan of quizzes. Love a quiz. And we know how smart you are. So I'm expecting a very strong score here. No pressure, but I have big hopes. Okay. Are you

ready? Yes. I was born ready. Fabulous. Here we go. Three, two, one. The study of what we now call science developed out of what kind of philosophy? Oh, natural philosophy. It was. Question two. Which saintly German female polymath, who loved a bit of music, was born in 1098? It was Hildegard of somewhere, but let's not pin her down. Yeah, Hildegard of somewhere, but let's not pin her down. Yeah, Hildegard of Bingen.

You can have that. Question three. Ibn al-Haytham was a visionary pioneer in which field of science? Oh, in vision and the eye and in light. Yeah, optics, absolutely. Question four. Name one of the things that came out of China in terms of its technology. Gunpowder. Yes.

Gunpowder is correct. You could have had a compass, gunpowder, paper or printing. Question five. Hereford Cathedral has a beautiful medieval map on the wall. What is its name? It's Mapus Mundi, isn't it? Is that right? Mapus Mundi.

Yeah, absolutely. Well done. Question six. Al Idrisi's Eurasian map, the Tabula Rogeriana, looks a bit odd to us. Why? Because it's upside down to us. Absolutely. South is in the north.

Question seven. Elmer of Malmbrie broke his legs doing what experiment? Just trying to fly like everyone else. Just trying to fly like a bird. Absolutely. Question eight. What did medieval alchemists try and do? Well, lots of things. Not just turning substances into gold but also um answer the unanswerable questions of the universe amazing answer perfect answer question nine islamic and christian instrument makers perfected which greek astronomical tool for finding stars location dates and times and seb has already shown us a couple it's the very sad astrolabe which we were all disappointed to see due to the fact that it wasn't chosen sebs heartbroken didn't light up and spin it didn't no no the beautiful astrolabe which i'm

very excited to have seen this for a perfect 10 arabic numerals actually came from where oh no i oh india from india yes 10 out of 10. Well done, Josie. Very, very impressive. Guys, that's the best test I've ever taken because I'd done the revision. Usually in my life it would be like, oh, I didn't revise that bit. But this is like, we did just do it. You've obviously had an ingenious instructor in Dr. Seb. And listeners, if your taste buds are tingling for the history of STEM, or is it STEM-mm?

Why not check out our episode on ancient Greek and Roman medicine? Or you can get to grips with Mesopotamian maths and mental health in the Ancient Babylonians episode. And remember, if you've had a laugh, if you've learned some stuff, please share the podcast with your friends or leave a review online and make sure to subscribe to You're Dead to Me on BBC Sounds so you never miss an episode. A huge thank you again to our guests in History Corner, the sensational Dr. Seb Falk from the University of Cambridge. Thank you, Seb.

Thank you so much for having me. And in Comedy Corner, the jolly excellent Josie Long. Thank you, Josie. Thank you so much for having me. It was great. And to you, lovely listener, join me next time as we put another historical hypothesis to the test. But for now, I'm off to go and try and make the elixir of life out of hamster poo and wagon wheels.

Bye! You're Dead to Me was a production by The Athletic for BBC Radio 4. of life out of hamster poo and wagon wheels. Bye! Lifelines, a new series of the multi-award winning Radio 4 drama, now available as a podcast. Sometimes heart-stopping. Sometimes heart-starting. Always matters of life and death. Ambulance service, is the patient breathing and conscious? Subscribe to Lifelines on BBC Sounds.