God's Philosophers E-Book

James Hannam

• Herausgeber: Icon Books
• Kategorie: Geisteswissenschaft
• Sprache: Englisch

Seitenzahl: 687

Veröffentlichungsjahr: 2009

Beschreibung

This is a powerful and a thrilling narrative history revealing the roots of modern science in the medieval world. The adjective 'medieval' has become a synonym for brutality and uncivilized behavior. Yet without the work of medieval scholars there could have been no Galileo, no Newton and no Scientific Revolution. In "God's Philosophers", James Hannam debunks many of the myths about the Middle Ages, showing that medieval people did not think the earth is flat, nor did Columbus 'prove' that it is a sphere; the Inquisition burnt nobody for their science nor was Copernicus afraid of persecution; no Pope tried to ban human dissection or the number zero. "God's Philosophers" is a celebration of the forgotten scientific achievements of the Middle Ages - advances which were often made thanks to, rather than in spite of, the influence of Christianity and Islam. Decisive progress was also made in technology: spectacles and the mechanical clock, for instance, were both invented in thirteenth-century Europe. Charting an epic journey through six centuries of history, "God's Philosophers" brings back to light the discoveries of neglected geniuses like John Buridan, Nicole Oresme and Thomas Bradwardine, as well as putting into context the contributions of more familiar figures like Roger Bacon, William of Ockham and Saint Thomas Aquinas.

Leseprobe

God’s Philosophers

HOW THE MEDIEVAL WORLD LAID THE FOUNDATIONS OF MODERN SCIENCE

JAMES HANNAM

ICON BOOKS

Published in the UK in 2009 by Icon Books Ltd, Omnibus Business Centre, 39–41 North Road, London N7 9DP email: [email protected]

This electronic edition published in 2009 by Icon Books

ISBN: 978-1-84831-158-9 (ePub format)

ISBN: 978-1-84831-159-6 (Adobe ebook format)

Printed edition (ISBN: 978-1-84831-070-4) Sold in the UK, Europe, South Africa and Asia by Faber & Faber Ltd, Bloomsbury House, 74–77 Great Russell Street, London WC1B 3DA or their agents

Distributed in the UK, Europe, South Africa and Asia by TBS Ltd, TBS Distribution Centre, Colchester Road Frating Green, Colchester CO7 7DW

This edition published in Australia in 2009 by Allen & Unwin Pty Ltd, PO Box 8500, 83 Alexander Street, Crows Nest, NSW 2065

Distributed in Canada by Penguin Books Canada, 90 Eglinton Avenue East, Suite 700, Toronto, Ontario M4P 2YE

Text copyright © 2009 James Hannam The author has asserted his moral rights.

No part of this book may be reproduced in any form, or by any means, without prior permission in writing from the publisher.

Typeset by Marie Doherty

To Vanessa

CONTENTS

List of Illustrations

Map of medieval Europe

Introduction: The Truth about Science in the Middle Ages

Chapter 1: After the Fall of Rome: Progress in the Early Middle Ages

Chapter 2: The Mathematical Pope

Chapter 3: The Rise of Reason

Chapter 4: The Twelfth-Century Renaissance

Chapter 5: Heresy and Reason

Chapter 6: How Pagan Science was Christianised

Chapter 7: Bloody Failure: Magic and Medicine in the Middle Ages

Chapter 8: The Secret Arts of Alchemy and Astrology

Chapter 9: Roger Bacon and the Science of Light

Chapter 10: The Clockmaker: Richard of Wallingford

Chapter 11: The Merton Calculators

Chapter 12: The Apogee of Medieval Science

Chapter 13: New Horizons

Chapter 14: Humanism and the Reformation

Chapter 15: The Polymaths of the Sixteenth Century

Chapter 16: The Workings of Man: Medicine and Anatomy

Chapter 17: Humanist Astronomy and Nicolaus Copernicus

Chapter 18: Reforming the Heavens

Chapter 19: Galileo and Giordano Bruno

Chapter 20: Galileo and the New Astronomy

Chapter 21: The Trial and Triumph of Galileo

Conclusion: A Scientific Revolution?

Suggestions for Further Reading

Timeline

List of Key Characters

Notes

Bibliography of Works Cited

Acknowledgements

LIST OF ILLUSTRATIONS

1.

Ottoman astrolabe from the Musée de l’Institut du Monde Arabe, Paris

2.

Map from Isidore of Seville, Etymologiae (Augsburg: Günther Zainer, 1472)

3.

Diagram of the universe from Peter Apian, Cosmographia (Antwerp: Arnold Berckmann, 1539)

4.

Manuscript illumination by Laurentius de Voltolina from the Kupferstichkabinett, Staatliche Museen zu Berlin

5.

Manuscript illumination from Bible Moralisee, Vienna, Österreichische Nationalbibliothek, MS Codex Vindobonensis 2554

6.

Manuscript initial from Johannitius, Isagoge, Bethesda MA, National Library of Medicine, MS DeRicci [78]

7.

Photograph of a large trebuchet

8.

Eastern and western Arabic numerals compared to modern western numerals

9.

Diagram from Nicole Oresme’s De configurationibus qualitatum, Florence, Biblioteca Nazionale Centrale, MS Conv. Soppr. J. IX. 26

10.

A map of the world from Ptolemy, Geographia (Ulm: Leonard Hol, 1482)

11.

Woodcut from Johannes de Ketham, Fasiculo de medicina (Venice: Zuane & Gregorio di Gregorii, 1494)

12.

Woodcut of a standing flayed figure from the studio of Titian in Andreas Vesalius, De fabrica corporis humanis (Basle: Joannes Oporinus, 1543)

13.

A woodcut of a uterus from Vesalius, De fabrica

14.

Model of the universe from Johann Kepler, Mysterium cosmographicam (Tübingen: Georgius Gruppenbachius, 1596)

15.

A diagram from Galileo Galilei, trans. Henry Carew and Alfonso de Salvio, Dialogues Concerning Two New Sciences (New York: Macmillan, 1914)

16.

A diagram from William Heytesbury, Regule solvendi sophismata (Venice: Bonetus Locatellus, 1494)

Map of medieval Europe

INTRODUCTION

The Truth about Science in the Middle Ages

The most famous remark made by Sir Isaac Newton (1642– 1727) was: ‘If I have seen a little further then it is by standing on the shoulders of giants.’1 Most people assume that he meant his scientific achievements were built on the discoveries of his predecessors. In the same letter, he alludes to René Descartes (1596–1650), the French philosopher and mathematician, so presumably he was one of Newton’s giants. Few people realise, however, that Newton’s aphorism was first coined in the twelfth century by the theologian Bernard of Chartres (who died around 1130).2 Even fewer are aware that Newton’s science also has its roots embedded firmly in the Middle Ages. This book will show just how much of the science and technology that we now take for granted has medieval origins.

The achievements of medieval science are so little known today that it might seem natural to assume that there was no scientific progress at all during the Middle Ages. The period has had a bad press for a long time. Writers use the adjective ‘medieval’ as a synonym for brutality and uncivilised behaviour. Recently, the word has affixed itself to the Taliban of Afghanistan whom commentators routinely describe as throwbacks to the Middle Ages, if not the Dark Ages. Even historians, who should know better, still seem addicted to the idea that nothing of any consequence occurred between the fall of the Roman Empire and the Renaissance. In 1988, Daniel Boorstin’s history of science The Discoverers referred to the Middle Ages as ‘the great interruption’ to mankind’s progress. William Manchester, in his 1993 book A World Lit Only by Fire, described the period as ‘a mélange of incessant warfare, corruption, lawlessness, obsession with strange myths and an almost impenetrable mindlessness’. Charles Freeman wrote in The Closing of the Western Mind (2002) that this was a period of ‘intellectual stagnation’. He continued, ‘It is hard to see how mathematics, science, or their associated disciplines could have made any progress in this atmosphere.’3

Closely coupled to the myth that there was no science worth mentioning in the Middle Ages is the belief that the Church held back what meagre advances were made. The idea that there is an inevitable conflict between faith and reason owes much of its force to the work of nineteenth-century propagandists such as the Englishman Thomas Huxley (1825–95) and the American John William Draper (1811–82). Huxley famously declared: ‘Extinguished theologians lie about the cradle of every science, as the strangled snakes beside that of Hercules.’4 Draper was a participant in the notorious debate on evolution between Huxley and the bishop of Oxford, Samuel Wilberforce (1805–73), in 1860, when the question arose of whether Huxley was descended from an ape on his mother’s or father’s side. Draper wrote the massively influential History of the Conflict between Religion and Science, which cemented the conflict hypothesis into the public imagination.

More recently, we have seen a real-life conflict between evolution and creationism. Conservative Christians and Muslims have launched an all-out assault on Darwinism. As this phenomenon shows, it is certainly true that particular religious doctrines can be in conflict with scientific theories. However, it does not follow that such hostility is inevitable. During the Middle Ages, the Catholic Church actively supported a great deal of science, but it also decided that philosophical speculation should not impinge on theology. Ironically, by keeping philosophers focused on nature instead of metaphysics, the limitations set by the Church may even have benefited science in the long term. Furthermore and contrary to popular belief, the Church never supported the idea that the earth is flat, never banned human dissection, never banned zero and certainly never burnt anyone at the stake for scientific ideas. The most famous clash between science and religion was the trial of Galileo Galilei (1564–1642) in 1633. Academic historians are now convinced that this had as much to do with politics and the Pope’s self-esteem as it did with science. The trial is fully explained in the last chapter of this book, in which we will also see how much Galileo himself owed to his medieval predecessors.

The denigration of the Middle Ages began as long ago as the sixteenth century, when humanists, the intellectual trendsetters of the time, started to champion classical Greek and Roman literature. They cast aside medieval scholarship on the grounds that it was convoluted and written in ‘barbaric’ Latin. So people stopped reading and studying it. The cudgels were subsequently taken up by English writers such as Francis Bacon (1561–1626), Thomas Hobbes (1588– 1679) and John Locke (1632–1704). The waters were muddied further by the desire of these Protestant writers not to give an ounce of credit to Catholics. It suited them to maintain that nothing of value had been taught at universities before the Reformation. Galileo, who thanks to his trial before the Inquisition was counted as an honorary Protestant, was about the only Catholic natural philosopher to be accorded a place in English-language histories of science.

In the eighteenth century, French writers like Voltaire (1694–1778) joined in the attack. They had their own issues with the Catholic Church in France, which they derided as reactionary and in cahoots with the absolutist monarchy. Voltaire and his fellow philosophes lauded progress in reason and science. They needed a narrative to show that mankind was moving forward, and the story they produced was intended to show the Church in a bad light. ‘Medieval philosophy, bastard daughter of Aristotle’s philosophy badly translated and understood’, wrote Voltaire, had ‘caused more error for reason and good education than the Huns and the Vandals.’5 His contemporary Jean le Rond d’Alembert (1717–83) edited an immense encyclopaedia that became the epitome of the philosophes’ achievement. D’Alembert’s influential Preliminary Discourse to this magnum opus set out the now traditional story of how scientific progress had been held back by the Church during the Middle Ages. He blamed ‘the condition of slavery into which almost all of Europe was plunged and the ravages of superstition which is born of ignorance and spawns it in turn.’6 But now, D’Alembert said, in his own time rational men could throw off the yoke of religion.

John William Draper and Thomas Huxley introduced this thesis to English readers in the nineteenth century. It was given intellectual respectability through the support of Andrew Dickson White (1832– 1918), president of Cornell University. The hordes of footnotes that mill around at the bottom of each page of his book A History of the Warfare of Science with Theology give the illusion of meticulous scholarship.7 But anyone who checks his references will wonder how he could have maintained his opinions if he had read as much as he claimed to have done.

The great weight of the assault on the Middle Ages carried on into the twentieth century. Popular historians based their work on previous popular histories and perpetuated the myth that the period was an interruption to mankind’s progress. Television shows by Carl Sagan, James Burke and Jacob Bronowski handed the thesis on to a new generation. Even when someone discovered evidence of reason or progress in the fourteenth and fifteenth centuries, it could easily be labelled ‘early-Renaissance’ so as to preserve the negative connotations of the adjective ‘medieval’.

The fight back began 100 years ago with the work of a French physicist and historian called Pierre Duhem (1861–1916). While researching an unrelated matter, he came across a vast body of unread medieval manuscripts. What Duhem found in these dusty tomes amazed him. He quickly realised that science in the Middle Ages had been sophisticated, highly regarded and essential to later developments. His work was carried forward by the American Lynn Thorndike (1882–1965) and German Anneliese Maier (1905–71), who refined and expanded it. Today, the doyens of medieval science are Edward Grant and David Lindberg. They have now retired, but their students already occupy exalted places in the universities of North America. As scholars explore more and more manuscripts, they reveal achievements of the natural philosophers of the Middle Ages that are ever more remarkable.

Popular opinion, journalistic cliché and misinformed historians notwithstanding, recent research has shown that the Middle Ages was a period of enormous advances in science, technology and culture. The compass, paper, printing, stirrups and gunpowder all appeared in western Europe between AD500 and AD1500. True, these inventions originated in the Far East, but Europeans developed them to a far higher degree than had been the case elsewhere. The Italian doctor, mathematician and astrologer Jerome Cardan (1501–76) wrote that next to the compass, printed book and cannon, ‘the whole of the ancient world has nothing to compare.’8 A compass allowed Christopher Columbus (1451–1506) to navigate his way across the Atlantic Ocean, sailing far from the sight of land to discover the New World in 1492. The development of printing and paper meant that an incredible 20 million books were produced in the first 50 years after Johann Gutenberg (c.1398–1468) had published his printed Bible in 1455.9 This dwarfed the literary output of antiquity. Printing probably had an even greater effect than gunpowder which, like the stirrup before it, revolutionised warfare and allowed Europeans to dominate the rest of the world.

Meanwhile, the people of medieval Europe invented spectacles, the mechanical clock, the windmill and the blast furnace by themselves. Lenses and cameras, almost all kinds of machinery and the industrial revolution itself all owe their origins to the forgotten inventors of the Middle Ages. Just because we don’t know their names, this does not mean that we should not recognise their achievements.

Most significantly, the Middle Ages laid the foundation for the greatest achievement of western civilisation, modern science. It is simply untrue to say that there was no science before the ‘Renaissance’. Once medieval scholars got their hands on the work of the classical Greeks, they developed systems of thought that allowed science to travel far further than it had in the ancient world. Universities, where academic freedom was guarded from royal interference, were first founded in the twelfth century. These institutions have always provided scientific research with a safe home. Even Christian theology turned out to be uniquely suited to encouraging the study of the natural world, because this was believed to be God’s creation.

Today, when we talk about ‘science’, we have in mind a clear and specific meaning. We picture a laboratory where researchers are carrying out experiments. But the word ‘science’ once had a much broader definition than it does now. The word comes from scientia, which means ‘knowledge’ in Latin. Science encompassed all intellectual disciplines, including politics, theology and philosophy. Theology was, famously, the queen of them all. The study of nature as a separate subject was called ‘natural philosophy’, and it is this term that will be used throughout this book. One of the essential lessons of history is that if we use our own categories to describe the past we will seriously misjudge it. Instead, it is important to understand where people in the Middle Ages were coming from and to understand them on their own terms. Part of doing this involves looking at subjects that we would consider unscientific today. To medieval people magic, astrology and alchemy were all considered to be ‘sciences’. More surprisingly, these arcane disciplines contributed directly to modern science by providing alternative ways of comprehending and manipulating the natural world.

The distinction between medieval natural philosophy and modern science is a subject of some debate among scholars today. However, one difference is immediately clear; modern science is naturalistic with no room for the supernatural. From the beginning of the nineteenth century, science has excluded God from the laboratory. In contrast, for the medieval natural philosopher, God was invariably central to any considerations about nature.

Modern science is a very specific kind of knowledge that blends empirical experimentation with rational analysis. Today we take it for granted and trust it to provide us with accurate information about nature. It is hard to believe that a few centuries ago, this scientific way of thinking hardly existed. Before the edifice of modern science could be built it required the strong foundations that were laid for it in the Middle Ages. The cornerstone was a widespread acceptance of reason as a valid tool for discovering the truth about our world. Clearly, this could not happen without the approval of the Church, which at the time was the guardian of almost all intellectual endeavours. This meant that the development of reason and its relationship with faith are both important parts of our story. So prevalent did rational argument become among philosophers during the Middle Ages that the period deserves to be thought of as the beginning of the ‘Age of Reason’.10

Some historians of science have had a habit of lauding individuals who seem to echo our own prejudices or appear more ‘modern’ than their contemporaries. When we hear about someone from the past who anticipated our own beliefs, we tend to label them ‘ahead of their time’. In fact, no one is ahead of his or her time. On closer examination, we always find that people are rooted firmly into their own cultural milieu. The best example of this is probably Leonardo da Vinci (1452–1519). A recent biographer, Michael White, even called him ‘the first scientist’.11 But surprisingly, despite being a genius, Leonardo had no impact on the development of western science at all. His influence was entirely in the arts. His lack of focus and constant experimentation prevented him from having as much success even in that field as he could have had. The reason no one followed Leonardo’s scientific ideas is that he didn’t tell anyone about them. His reputation today as a man of science is based on his famous notebooks, but these did not become known until centuries after his death. His secrecy was nothing to do with fear of prosecution or a belief that the Church would try to curtail his work. It was simply a character flaw that made him refuse to share his insights.12 He even disguised his notes by using mirror writing to make them illegible unless they were seen reflected in a mirror. Consequently, and despite his enormous reputation, we will hear no more about him in these pages.13

Another common mistake is to divide up history into discrete periods and then give them names containing clear value judgements. This can be extremely misleading. For example, we are commonly taught that there was a Renaissance, which was ‘a good thing’, the Dark Ages, which were ‘bad’ and the Enlightenment, which was ‘very good indeed’. How could anyone disapprove of being enlightened when the alternative, presumably, was to be benighted? Renaissance means ‘rebirth’, with the clear implication that previously civilisation had been well and truly dead. The term ‘Dark Ages’ was coined in the fourteenth century by the Italian writer Francisco Petrarch (1304–74). What he meant was that between the ancient world of Rome and his own time, nothing much happened. For 1,000 years, mankind had stood still. As we shall see, the advance of science provides one of the best examples of the injustice of these historical labels. The first appearance of the term ‘the Middle Ages’, a less pejorative label, was in the fifteenth century when it is used by various Italian humanists.14

One might think that the other names we give to historical periods also date back centuries, but in fact they nearly all originated in nineteenth-century France. French historians had a very clear idea that the past was the story of mankind’s progress towards their own civilisation, which they regarded as the pinnacle of human progress. The English were just as bad. The Victorians invented a story about the triumph of civilisation through Protestantism, free markets and a benevolent British Empire. They even believed that this triumph had been made possible by frequent victories over the French. If we really are going to understand history, we will have to do away with prejudicial labels like ‘the Dark Ages’ and ‘the Enlightenment’, or at least learn to treat them with considerable scepticism.

On the other hand, some of the customary names and adjectives used for historical periods are just too convenient and so we will have to employ a few of them. The dates assigned to each period are, inevitably, rather arbitrary. According to this schema, the early Middle Ages (which used to be called the Dark Ages) extend from the fall of the western Roman Empire in AD476 up until 1066; the Middle Ages proper start at that point and end in 1500 when we enter the early modern period. All dates are AD unless otherwise stated and AD/ BC designators are used whenever there might be some confusion. There is a trend among historians today to replace the old system of AD and BC with CE (for Common Era) and BCE (for Before Common Era) as a non-Christian alternative. That seems right for a history of China or Mesoamerica, but for the European Middle Ages AD and BC remain entirely appropriate.

Briefly stated, the plan of this book is as follows. It tells the story of how natural philosophy in the Middle Ages led to the achievements of modern science. We begin with a review of the early Middle Ages up to AD1000. During this period, western Europe recovered from the collapse of the Roman Empire and began to rebuild itself with the help of several important new inventions. We will see how agriculture improved and how much a well-educated person at the time could expect to know about natural philosophy.

In the third and fourth chapters, we will learn how the West recovered the heritage of ancient Greek learning. This had been lost to Europe when the Roman Empire collapsed, but was regained from Arab and Byzantine sources. This wave of new knowledge inevitably caused concern to the authorities. Chapter 5 tells of how the Christian Church became increasingly concerned about heresy in the twelfth century. However, it eventually came to terms with Greek philosophy. And as we will see in chapter 6, a great deal of debate and argument was resolved by the titanic figure of Saint Thomas Aquinas (1225–74), the greatest scholar of the Middle Ages.

Chapter 7 looks at why, if you fell ill in the Middle Ages, you would be better off praying at a holy shrine than visiting a doctor. Chapter 8 examines two subjects that the Church treated with suspicion but which nonetheless enjoyed great popularity – alchemy and astrology. In chapter 9 we meet Roger Bacon, a dedicated alchemist, who devoted his life to the study of nature because he thought it would be a useful tool for converting Muslims to Christianity before the imminent end of the world. In chapter 10 we meet another less celebrated but no less fascinating Oxford scholar – Richard of Wallingford (1292–1336). Besides his achievements in astronomy, he built one of the finest and most complicated clocks of the Middle Ages, despite suffering from the dreadful affliction of leprosy.

Once Thomas Aquinas had Christianised Greek philosophy, medieval scholars could build on it. Chapters 11 and 12 demonstrate the advances in scientific thought that were made at the universities of Oxford and Paris in the fourteenth century. Two areas saw particular progress – the implications of the earth’s rotation and the motion of accelerating objects.

In chapter 13, we will see how new inventions in the late Middle Ages had a profound effect on European society and, thanks to the voyages of Columbus and others, the rest of the world as well. Ascertaining whether or not the earth is flat was the last thing on Columbus’s mind.

Chapter 14 examines the impact of humanism and the Protestant Reformation on science and technology. Humanists recovered important ancient Greek mathematical texts but also rejected the advances made in philosophy during the Middle Ages. The Reformation broke the power of the Catholic Church to control science but also made it less tolerant of new ideas.

Although ‘the Renaissance’ is often associated with the beginning of modernity, it also saw a surge in magical belief that especially affected those who were at the cutting edge of science. Chapter 15 looks at these links. In chapter 16, we will see how human dissection arose in Europe and helped us to understand the machinery of our own bodies.

Chapter 17 relates the story of how Nicolaus Copernicus (1473– 1543) decided that the earth orbited the sun, and not the other way around as everybody else thought. He was no isolated genius, though, and owed a great deal to his medieval and Islamic forebears. Chapter 18 shows how Copernicus’s radical idea was adapted and proved by Johann Kepler (1571–1630).

The last three chapters look at Galileo and his contemporaries. He too took ideas from earlier thinkers and used them to construct his own theories about matter and motion. Galileo pulled together many of the strands of medieval thought to form the basis of modern science. It is with him that our story concludes.

CHAPTER 1After the Fall of Rome: Progress in the Early Middle Ages

To understand why historians no longer feel comfortable with the term the ‘Dark Ages’, you only have to visit the British Museum in London to admire the treasure found at Sutton Hoo in Suffolk. Archaeologists discovered the grave of an Anglo-Saxon king there in 1939. It was filled with the most marvellous objects, lying in the rotted hulk of an entire ship that was buried under a mound. The craftsmen of seventh-century East Anglia who produced these stunning artefacts in gold, glass and precious stones were certainly no savages. They used materials from all over Europe to fashion buckles and accoutrements fit for a king. Even with a magnifying glass, it is difficult to see all of the exquisite detail on the jewelled purse lid and shoulder clasps. The silver drinking cups were manufactured in the eastern Mediterranean (although admittedly they are not of the highest quality)1 and travelled to England along trade routes that probably took English wool and slaves in the opposite direction.

Although invented much earlier, the term ‘Dark Ages’ became popular in the nineteenth century. It is clear that dismissing half a millennium as being filled with gloom was not intended to flatter the people who lived during it. Some historians explained that by ‘Dark’, they only meant that relatively few written sources survive for the period compared to those immediately before and afterwards. What they actually meant is that very little of interest happened. Today we have come to realise that we cannot so easily write off the period. Roger Collins, in his standard work Early Medieval Europe 300–1000, states: ‘The centuries covered by this book constitute a period of the greatest significance for the future development, not only of Europe, but in the longer term, of much else of the world.’2 So little credence does Dr Collins give to the term ‘Dark Ages’ that he does not even bother to mention that he refuses to use it.

Ploughs, Horseshoes and Stirrups: New Technology in the Early Middle Ages

The royal treasure buried at Sutton Hoo tells us something about the luxuries available to the Anglo-Saxon elite; however, to learn about the lives of common men and women we have to look elsewhere. Luckily, we have a very good idea about everyday life at the end of the early Middle Ages because of a great administrative project set in motion by William the Conqueror (1028–87). After he had subjugated England following the Battle of Hastings, William wanted to know exactly what resources the country possessed. The resulting census, the Domesday Book, gives us a fantastic opportunity to step back in time and see the world through medieval eyes. Near the start of the Domesday Book is a short entry for Otham in Kent. This village, where much of the present book was written, lies on the southern bank of the River Len, just to the east of the county town of Maidstone. It contains more than its fair share of grand medieval manors, because the local ragstone quarry provided employment for stonemasons who could afford big timber-framed houses. The stone had been extracted since Roman times and is rumoured to have been used to build the ancient walls of London itself. However, by the time William the Conqueror’s agents arrived to compile the Domesday Book, the quarry was silent and they don’t mention it.

Anglo-Saxons preferred to build with wood, largely because trees were so plentiful. Many more ancient stone buildings do survive around the Mediterranean than in England, but this is more to do with the comparative lack of wood suitable for large-scale construction. In Japan, stone was rarely used right up until the nineteenth century.3 Anglo-Saxons reserved stone for when they wanted to make a big impression, which was usually when they were erecting a cathedral. Otham had no stone buildings. Even the surviving houses of the stonemasons are largely made of wood.

The Domesday Book entry for Otham, expanded from the rather terse original, reads:

Geoffrey of Rots holds Otham from the bishop of Bayeux. It contains three hides of land. There is land enough to provide work for two and half ploughs of which the Lord holds land for one. Nine villagers and three smallholders share one plough and the Lord has another. There are a church, two slaves, a mill generating five shillings a year, meadow of three acres and woodland supporting eight pigs.4

The lord of the manor in 1086, Geoffrey of Rots, was a knight from a small village near the city of Caen in Normandy. Nine villagers and their families lived in Otham together with three smallholding farmers. There was a church, which was certainly wooden too. The present church, set across the fields from the rest of the village, dates from the thirteenth century but may well occupy the same site as the previous Anglo-Saxon one. There were three acres of meadow where the villagers’ cattle would graze, and enough woodland for eight foraging pigs.

So far, the scene doesn’t sound all that different from how we might expect a Roman village to appear. But the entry in the Domesday Book contains two details that tell us we are dealing with a medieval settlement. The first of these is the mention of ploughs. From almost the dawn of agriculture, peasants had tilled their land with nothing more than a metal-tipped wooden spike, perhaps pulled by an ox, that gouged a furrow out of the ground. Then, in the tenth century AD, another method of tilling the soil arrived in England from the continent.5 A team of eight oxen, yoked two abreast and pulling a heavy iron plough, now worked the fields of Otham. The new machine had a blade that cut into the earth; a ploughshare that dug in at right angles and a mouldboard behind that actually turned the soil over as it went. This had many beneficial effects. Turning over the soil buried any weeds growing in the field so that they died and improved the soil’s fertility. It also increased the amount of water that the ground could hold. Finally, it was much more efficient to operate than the old scratch plough because it attacked a larger cross-section of soil.6 However, the new plough was large and a single peasant could hardly afford one. In fact, the Domesday Book makes it clear that the peasant families of Otham had just one plough between them, with another belonging to the Lord of the Manor. Such was its effectiveness, however, that one plough was all the peasants needed to till their land.

Also on show in the fields of Otham were Geoffrey of Rots’ horses. One of the factors behind the Norman victory at the Battle of Hastings had been the superior military technology at their command. The invention that most transformed warfare in the early Middle Ages was the humble stirrup. Ancient horsemen had clung to their mounts with their knees or had had the help of high pommels on their saddles to steady them. Without foot supports, a horseman was quite unable to bring his horse’s weight to bear through the weaponry that he was carrying because he was always at risk of slipping off the side of his mount. The only strength that could go into the delivery of either a spear or a sword thrust was his own. And fighting with a sword was risky because if the rider should miss his opponent he would have the grip of his knees or saddle horns to prevent himself from becoming overbalanced and falling off. In battle, falling off was worth avoiding at all costs. As a result, ancient cavalry enjoyed the advantages of speed and manoeuvrability that made them good skirmishers, but were less useful as shock troops. The stirrup changed all that. Now, a horseman could sit firmly supported in his saddle both laterally and dorsally. He was able to move as one with his mount and bring its momentum into play. He could brace his spear against his side and transmit the full force of his charging horse into the enemy, transforming the cavalryman into the mounted knight.7

The Normans were among those who took full advantage of these developments. When Geoffrey of Rots went into battle, he rode a horse and carried a lance. The Anglo-Saxons ranged against him at Hastings fought on foot and with battleaxes. Saxon swords were actually marvels of metallurgy, but they were extremely expensive compared to an axe so only the richest nobles could afford them. That is not to say that the Saxon battleaxe, combined with their use of a wall of shields to defend themselves, was not a formidable weapon. But once the shield-wall was breached, as happened at Hastings when the Saxons pursued the retreating Normans, they were no match for the mounted knights.

Horses were just as valuable during peacetime as they were in a war. In eleventh-century Otham, oxen still made up the plough teams, but these were not the ideal draft animal. Even given their more expensive upkeep costs, horses were better at ploughing because they were able to pull faster. However, to be effective, the horse needed a harness that allowed it to use all of its strength. The new horse collar, developed at some point after AD700, was a huge improvement on previous harnesses that had tended to put pressure on the windpipe if the animal tried to pull with anything like its full might. Roman law had restricted the load to which a horse could be attached to 1,100 pounds, about half what they are capable of hauling, in all likelihood to protect the animal from exhaustion.8 From the eleventh century, haulage became yet more efficient as the ‘whippletree’ began to make an appearance. This oddly named device was just a log chained horizontally in front of a plough or cart. The draft animals themselves were harnessed to the whippletree rather than directly to the load. Using the log equalised the force from the horses or oxen, so that turning was more efficient and animals of different strengths could be harnessed together.9

The iron horseshoe also added to the effectiveness of the beast. In wet terrain, unprotected hooves could be quick to rot and the shoe increased their durability. Taken together, their enhanced effectiveness as both a weapon of war and a draft animal made horses increasingly indispensable as the Middle Ages wore on.

The fields in which the villagers grew their crops would also have looked different from how they had in Roman times. Much of the change was due to the introduction of three-field crop rotation. Farmers had long been aware of the importance of rotating their crops – allowing some fields to lie fallow as pasture while varying the crops planted in others. This idea advanced further in the early Middle Ages when three-field rotation began to appear. Under this system, the fields of Otham were split into three groups. The first group lay fallow as pasture for the villagers’ animals, especially the team of plough oxen whose manure added to the richness of the field. The villagers planted the second group in the autumn with grain as they had done since time immemorial. However, they also planted beans in the spring in the third group of fields, which further improved the soil and provided a broader diet.10 Beans, we now know, take nitrogen out of the air and bacteria in their roots turn it into natural fertiliser. Today in Otham, beans are still planted purely to improve the productivity of the soil.

Increased volumes of agricultural produce drove the need for new technology to process it all. This is the relevance of the second revealing detail in Otham’s entry in the Domesday Book – the presence of a mill. Wheat and barley were no longer ground by animal or manpower, but with the aid of a watermill. The River Len in Otham provides the perfect location for one of these. It is too narrow to be navigable, but powerful enough to turn the twelve waterwheels that once lined its banks. The Domesday Book states that the Otham mill generated an income of five shillings a year, which made it medium-sized. Watermills had existed in the ancient world, but the Romans did not adopt them in large numbers until the end of the Empire. In the early Middle Ages, they became increasingly common and the Domesday Book lists 5,624.11 Tidal mills were adopted on suitable estuaries, where a dam harnessed the high tide and released it through a channel containing a watermill. Finally, the first recorded European windmills appeared in Normandy and East Anglia during the twelfth century and they quickly spread all over those parts of northern Europe where rivers suitable for watermills were not available.12

Taken together, these improvements in agriculture led to a population explosion because better farming techniques meant that the same acreage could yield more food and support more people than before. Estimates for the population of France and the Low Countries rise from 3 million in AD650 to 19 million just before the arrival of the Black Death in AD1347. For the British Isles, the equivalent figures are 500,000 people and 5 million. In Europe as a whole, the population increased from less than 20 million to almost 75 million. These figures are of course estimates, if not guesstimates, but the upward trend is clear. For comparison, at the height of the Roman Empire about 33 million people lived in Europe. Well before AD1000, the population far exceeded what it was when the continent had been ruled by Rome, and remained above that level even after the Black Death had killed a third of the inhabitants of Europe in the fourteenth century.13

In his study of early-medieval technology, the great American historian Lynn White Junior (1907–87) concluded that the period ‘marks a steady and uninterrupted advance over the Roman Empire’.14 The popular impression that the early Middle Ages represented a hiatus in progress is the opposite of the truth. Even so, the fall of Rome and the replacement of the imperial administration with a patchwork of barbarian kingdoms meant that this was a very unsettled period to live through. In order to shed some light on these times, it will be helpful to summarise events in Europe between the fifth and eleventh centuries.

The Fall of Rome and the Rise of Islam

The Roman Empire had ruled much of Europe until the beginning of the fifth century AD. Beyond its frontiers, in modern Germany, barbarian tribes gathered and looked on the Empire with resentful eyes. When the Rhine froze over in AD406, they poured across the river and spread throughout the vast territory of the Empire. In 410, a barbarian tribe called the Goths sacked Rome, the first time it had fallen to a foreign army in seven centuries. This event caused deep shock as the news reverberated around the Empire. Although the state religion was Christianity, there were still plenty of pagans, especially among the noble families of Rome. They blamed the abandonment of the old religion for provoking the gods into inflicting this unprecedented disaster.15 It would not be the last time Rome was to fall. After narrowly avoiding the attentions of Attila the Hun (406–453) the city was sacked again in 455, this time by the Vandal tribe. The Goths had at least respected the sanctuary of the city’s churches, but the Vandals showed no such restraint and caused even greater devastation. This is the reason that the Vandals have given their name to anyone causing needless damage. By the late fifth century, the Roman Empire in the West was no more. The traditional date for the final fall is 476 when the last emperor abdicated.

Despite this disaster, it was by no means the end of the Empire. As well as western Europe, it had straddled a huge sweep of land from Egypt, around the Levant, through Asia Minor and thence to the Balkans. These provinces remained firmly in Roman hands. The Emperor ruled from the city of Constantinople, the capital of the Byzantine Empire, which was so called after ‘Byzantium’, the old Greek name for Constantinople. The Emperor Constantine (c.AD272–AD337) had re-founded the city in 330 to be his capital instead of Rome. This was a remarkably prescient act given the fate of Rome a century later, and it meant that the Empire’s centre of gravity swung to the East. Constantine’s other great claim to fame is that he made Christianity the official religion of the Empire, although he did not altogether outlaw paganism. His successors were less tolerant of the old religion, and by 400 most forms of pagan practice were illegal even if actually being a pagan was not.16

One of the most distinctive features of the Byzantine Empire, as opposed to the old Roman Empire, was that the Byzantines were predominantly Greeks. Although they continued to call themselves Romans, the use of Latin died out and Greek became the dominant language. In the ruins of the western half of the Empire, knowledge of Greek practically ceased to exist when the barbarian tribes took over or destroyed the Roman infrastructure. Previously, the best-educated Romans would have been fluent in Greek as well as their native Latin. On the other hand, the barbarians all spoke their own tongues and although Latin did survive as the language of the Church, a linguistic divide opened up between East and West. This was doubly unfortunate because, in the ancient world, it was Greek and not Latin that was the language of scholarship and philosophy. Suddenly, the West lost access to this tradition.

Western Europe was also cut off from imperial influence, as the Byzantine Emperors’ rule did not extend into the new kingdoms of the Saxons, Goths and Vandals. In this power vacuum, the local rulers took temporal control while the Church exercised supranational spiritual authority. The bishop of Rome had long maintained that he was at least first among equals with regard to the other Christian patriarchs, but this was largely irrelevant when real power, both secular and ecclesiastical, was in the hands of the Emperor. Then things changed. The retreat of the Emperors’ power to the eastern Mediterranean gave the bishop of Rome a free rein in the West. Only now did he become the Pope in the sense that we understand today as unquestioned head of the Catholic Church. The Popes set about organising the evangelisation of the barbarian kingdoms, and slowly Catholic missionaries converted them all to Christianity.

As the conversion of the barbarians gathered pace, the eastern half of the Empire faced a threat that sought to conquer it in the name of a new religion. Arab invaders from the East would certainly not convert to Christianity if they succeeded in occupying the territory of the Empire, because they possessed a vigorous faith of their own – Islam.

Islam owes its origin to the Prophet Mohammed (c.571–632), a native of the Arabian city of Mecca, who claimed that the angel Gabriel had visited him and dictated the text of the Holy Koran. At this time, neither of the great empires to the north, Byzantium and Persia (modern Iran), had annexed the deserts of the Arabian peninsula. They remained in the hands of nomadic tribes who made their living by trade and banditry. At the time that Islam was founded, Mecca had an important marketplace where traders could meet under truce and do deals before retiring back to the desert. The tribes were a nuisance to the settled people, especially when they raided caravans, but conquering the vast wilderness was out of the question. Most of the tribes still worshipped their traditional gods and Mecca also served as a place of pilgrimage for them. It was home to a holy rock called the Black Stone of the Kaaba. This had been held as sacred since before recorded history and it is still an object of veneration by Muslims after Mohammed co-opted it for Islam.

The Prophet began preaching the new religion in Mecca but his fellow countrymen rejected his message, forcing him to flee north to Medina, another desert trading centre. This journey in 622 marks the beginning of the Muslim calendar. In Medina, Mohammed met with much greater success and was eventually able to return to his home town of Mecca as a conqueror. Then, he turned his attention to the rest of the desert people, united them under the banner of Islam and formed an army capable of conquering much of the known world.

Beginning in the mid-seventh century, Muslim armies marched out of Arabia and rapidly conquered Persia and a large part of the Byzantine Empire. It was the perfect time for the Arabs to launch an attack. Persia and Byzantium had been deadly rivals for centuries but neither could ever defeat the other. This changed in the early seventh century when the Byzantine Empire finally smashed the power of Persia in a series of wars ending in 628. This was a great victory but after fighting each other to a standstill, neither of the empires was in a fit state to resist the Muslims’ advance. They annexed the entire Persian Empire and Byzantium fared little better, losing Palestine, Egypt and Syria in quick succession.

Islam’s success was partly down to its simplicity. It eschewed the complicated legal codes of Judaism (although it would later develop a legal system) and the rarefied theology of Christianity. Instead, Mohammed proposed a basic five-point plan for getting to heaven known as the five pillars of Islam.

First, Muslims must reject all Gods except Allah and accept Mohammed as his final, definitive prophet. Christians and Jews, as the recipients of older and incomplete revelations, could opt out from this requirement but paganism was beyond the pale. We often hear of Islam’s relative tolerance in that it accepted Christianity as a flawed but legal faith, whereas Christians considered Muslims to be infidels. In fact, this is more a matter of chronology than of tolerance. It is similar to Christians’ ill-tempered acceptance of Judaism as a faith that pre-dated their own. Like Jews in medieval Europe, Christians living under early Islamic rule were very much second-class citizens.

The second pillar of Islam is prayer five times a day. At the call of the muezzin from the mosque’s minarets, the faithful either assemble at the mosque or else unroll a prayer mat where they are. Muslims face Mecca while they pray. As Islam spread from the Atlantic to India through the eighth century, it became more difficult to determine in which direction Mecca lay. Scholars had to study the position of the stars to ensure that it was properly calculated and this helped to stimulate astronomy and trigonometry.

The third pillar is giving alms to the poor; the fourth, fasting during daylight hours in the holy month of Ramadan. Because the Muslim calendar follows the moon’s orbital cycle rather than the sun’s, its liturgical year is only 355 days. This means that Ramadan is a little earlier each year and moves through the seasons. The final pillar of Islam is the Hajj, which is a pilgrimage to Mecca, ideally undertaken once in the lifetime of every Muslim.

It would take another book to do justice to the great advances achieved by Arabs in the fields of mathematics, medicine and philosophy, let alone art and literature. However, it is essential to give a brief overview of this legacy because the inheritors of the Islamic tradition in science were western Christians. We saw earlier how a lack of knowledge of Greek cut off the West from much of its classical heritage. The Arabs did not have this problem because they had conquered a large number of Greek-speakers. They were also able to call upon the services of Syrian Christians who spoke a language called Syriac, which is related to Arabic. To take advantage of this, the Caliph, ruler of all Muslims and successor of Mohammed, founded a school in Baghdad called the ‘House of Wisdom’ where the cream of Greek science and philosophy was translated into Arabic. Scholars spread these works through the Islamic Empire, including Spain where western Christians first came across them.

However, it would be quite wrong to say that Muslims acted only as a conduit through which ancient learning could reach the West. The Byzantines independently preserved almost all of the most important surviving scientific texts in the original Greek, and few of them would have been lost without the Arab scribes.17 Rather, the importance of Muslim science lies in the innovative works of philosophy, mathematics and medicine that the Islamic world produced. The Arabic origin of mathematical terms such as algebra and algorithm are further indications of how much we owe to the Islamic Empire.18

After conquering much of the Byzantine Empire, Muslim armies carried on westwards along the North African coast, taking Carthage in modern Tunisia on their way to Morocco. When they had reached the Atlantic Ocean, they turned north and crossed the Straits of Gibraltar into Spain in 710. Within two decades they had conquered the Christian kingdoms of the Iberian peninsula, leaving only a strip of land along the northern coast in Christian hands. Finally, the Muslim armies traversed the Pyrenees and invaded France. Here, at last, they met their match in Charles (688–741), chief adviser to the king of France, at the Battle of Poitiers in October 732. His army formed a shield wall ‘holding together like a glacier’ which the enemy could not penetrate. Abdurrahman, the Muslims’ general, died in the battle and his army slipped away under cover of darkness to Spain, never to return in such numbers.19 Although Muslims at the time saw the defeat as merely a temporary setback, they never again seriously threatened France and Christian Europe was secure. Edward Gibbon (1737–94), the irreligious English historian, reflecting on the military conquests made by the Arabs, considered what might have happened if Charles had lost the battle. ‘Perhaps’, mused Gibbon mischievously, ‘the interpretation of the Koran would now be taught at the schools of Oxford and her pulpits might demonstrate to a circumcised people the sanctity and truth of the revelation of Mohammed.’20

The Foundation of the New Roman Empire

Charles was awarded the epithet of Martel, or ‘Hammer’, for defeating the Muslim invaders. Following his victory, he saw his power wax until he was effectively king of France rather than just the power behind the throne of a puppet monarch. Under him and his successors, France rapidly became the major power of western Europe. The most famous scion of the dynasty was his grandson Charlemagne (742–814), who expanded the territory under his control to include much of Italy and Germany. ‘Charlemagne’ simply means Charles the Great, and he is probably the only ruler actually to have greatness incorporated into his name. For Charlemagne, being king was not enough. He wanted more and at Rome on Christmas Day 800, the Pope crowned him Emperor. Allegedly, Charlemagne was unaware that this was about to happen, but we should take such pious anecdotes with a pinch of salt. Charlemagne also required a fine capital and he built his at Aix-la-Chapelle (or Aachen) in the Rhineland. His octagonal stone cathedral, still standing today, dominates the town and serves as the Emperor’s mausoleum.

Charlemagne is significant partly because he was a strong ruler who was able to control enough resources to fund a cultural revival, usually called the ‘Carolingian Renaissance’. Charlemagne himself was barely literate but he appointed the celebrated scholar Alcuin of York (c.735–804) to help foster learning in his capital and at other centres in his enormous Empire. Today we still have reason to be grateful for these efforts, as many works of classical Latin literature have come down to us because of them. Often the oldest manuscripts date from this period, recognisable from their distinctive caroline miniscule handwriting.21

Charlemagne also ordered that schools be set up at the cathedrals in his realm to ensure that there would be enough literate people to administer his Empire.22 Many of those who attended these schools went on to become clerics, but this was by no means compulsory. Merchants, lawyers and physicians could all expect to begin their education at the feet of a master appointed by the cathedral chapter.

Today Charlemagne is criticised for being so aggressive in spreading Christianity. His forced conversion of the newly conquered Saxons, his merciless treatment of prisoners and his acceptance of a role as the Popes’ enforcer all strike us as unchristian behaviour. However, the conversion of disparate tribes to a single religion brought them all together into a single spiritual unit. As a result the Church could, to some extent, enforce its prohibition against fighting between Christians and insist that their martial energies were directed externally.

On the Emperor’s death in 814, his sons divided his vast realm and then rapidly fell out with each other. The Empire had dissolved within two generations. The next dynasty to stand supreme in western Europe arose from the Saxons of Germany (not to be confused with the Saxons of England) whom Charlemagne had conquered and converted to Christianity. The historic divide between France and Germany, united under Charlemagne, dates from this period and specifically the refusal of the French monarchs to buckle under the Saxon yoke. The Holy Roman Empire, founded by the Saxon monarchs, included Germany, much of central Europe and Italy but never France. The French maintained their independence and prevented Europe ever again becoming a single political as well as religious unit. The first of the new Saxon Emperors was Otto I (912–973), crowned in 962. He was succeeded by his son Otto II (955–983) who was, in turn, followed by his son Otto III (980–1002). It is not surprising that historians call this period the Ottonian Age.23

By the time Otto III took the imperial throne, the barbarian invaders of the Roman Empire had coalesced into kingdoms and converted to Christianity. Agricultural production was being driven by improved technology and the population was expanding rapidly. Western Europe was still a backward corner of the world, but it was well on the way to catching up.

CHAPTER 2The Mathematical Pope

In the year 999, on Palm Sunday, Gerbert of Aurillac (c.940– 1003), the most learned man in Europe, was crowned Pope.1 As the papal tiara was placed on his head, Gerbert’s elevation to such a height from his humble beginnings in rural poverty must have seemed miraculous. During the Middle Ages, the princes of the Church tended to be related to the princes of the state, and there would not be another lower-class pope until the thirteenth century.2 Gerbert’s coronation took place in the Basilica of St John Lateran, the cathedral of Rome, which lies on the other side of the city from the Vatican. The building that stands on the site today is largely a seventeenth century creation, but we can have a good idea of what the old basilica looked like from studying ancient churches that have survived.3 At the end of the first millennium, the interior would have been a long box-like space called the nave, with stone walls and a wooden ceiling. The walls would have been supported by a row of pillars which allowed access to the aisles that ran down each side. At the far end of the nave was the apse, a semi-circular alcove before which stood the altar. The roof of the apse was a half dome, providing an artistic space that could dominate the whole length of the basilica. Typically, a golden mosaic of Christ triumphant stared out and would have made it clear who was the true master of the building. Along the walls of the nave, frescos of the saints would make the building a riot of colour. Just below the roof, a line of windows would have let in light and ensured that the building was not too gloomy despite the clouds of incense.

Packed into this richly decorated hall on that coronation day would have been a crowd of people as finely arrayed as the church itself. The clergy would be distinguished by their tonsured heads – the ceremonial shaving that marked them out as men of God. Any monks present would be plainly attired but most priests would wear their most splendid vestments. Foremost among them were the cardinals who represented the parish churches of Rome. They did not yet have the power to elect the Pope. That was the preserve of the noble families of the city who fought among themselves for control of the papacy. At the coronation, the members of each family would have sought to surpass their rivals with the splendour of their jewels and robes. On that day, however, they would have had to stand aside for a still greater power because the Holy Roman Emperor was in town. In truth, Gerbert owed his elevation to his patron and pupil Emperor Otto III, who was still only in his teens. Otto had seized control of Rome and, when the previous Pope had died, ensured the appointment of Gerbert in his stead. The new Pope knew where he stood. He took the pontifical name Sylvester II because the first Pope Sylvester had been a councillor to the Emperor Constantine.4 Thus, Gerbert’s ascent of the throne of St Peter in St John Lateran was supposed to signal a new partnership between Church and state. It never happened. Within four years, both Emperor and Pope were dead.

The Career of Gerbert of Aurillac

We know a good deal about Gerbert’s life because one of his pupils, a monk called Richer of Saint Remi (who died around 998), wrote a history of France giving plenty of attention to Gerbert’s career.5 We also have a collection of letters that Gerbert wrote, although most of these relate to church business and not to his personal life.6 He was born near Aurillac in south central France and entered the local monastery at an early age. Initially, he would not have been one of the monks – his origins were too humble for that. Monasteries had