A History of the World (33 page)

This must have something to do with territorial ambition. Just as the later saltwater Europeans were touching other continents and labouring to understand the Indian and Chinese civilizations, so the Abbasids stretched on land for some four thousand miles, from the Atlantic to the edges of India. Europeans needed new instruments to find their way across the oceans; Abbasid Muslims needed them to chart their way across deserts and mountain ranges, as well as across the sea. Europeans found new landscapes, plants and animals, which tested (and later overthrew) their ideas about how the world was made. Much earlier, Muslim thinkers had been confronted by ideas from many different sources, in an empire brimming with Jews, Greeks, Zoroastrian Persians and unorthodox Christians, and had struggled to make those ideas cohere.

They had nothing but contempt for the Christian Europeans. The geographer al-Masudi explained that because of their cold, dark climate ‘their bodies are large; their natures gross, their manners harsh, their understandings dull, and their tongues heavy’.
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Mathematics is the most obvious example of these Muslim thinkers’ success. In 762 Caliph al-Mansur had laid out his new capital at Baghdad in a perfect circle, his gracious compliment to the Greek mathematician Euclid. Al-Mansur was a ruler with the self-confidence to encourage a revival of Persian learning, and to reach out to help the Chinese, sending thousands of mercenaries to help in their local wars. At Baghdad, the House of Wisdom, which was something like a combined research centre, library and college, fizzed with arguments about law, astrology, medicine, geography and many other subjects. There, mathematics was particularly prized.

Why was this? One underlying reason was to do with astrology, the reading of the stars, which Muslims, like Christians, believed could foretell the future, but which required ‘the utmost precision in instrumentation and timekeeping, preparing star tables accurate not just to minutes of degrees but to seconds and beyond’.
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Another was that with accurate measurements they could produce proper maps of their vast domains. Furthermore, by understanding the rotation and curvature of the earth they could calculate Mecca’s exact direction when praying. Add to these mystical, imperial and religious concerns a love of numbers and patterns for their own sake, and the Abbasid fascination with maths makes perfect sense.

Trying to establish accurate figures for the circumference of the Earth, Caliph al-Mamun sent his surveyors into the desert to take readings of the sun’s altitude, dividing the men into two groups marching in opposite directions, measuring as they went, until their sun calculations showed they had travelled one degree on the meridian. In the 820s Europeans would not have understood what he was doing, never mind why – any more than South American natives understood sextants and telescopes when Captain Cook arrived. But Muslim mathematicians were not working in isolation. Some years before, in 771, a group of Hindu scholars had arrived at Baghdad from India with scientific texts, including an explanation of the sine function, which, developed by Islamic thinkers, would produce modern algebra.

The greatest mathematician of the age, Muhammad al-Khwarizmi, who was probably an Uzbek, perfected mathematical tables to show the exact positions of the sun, moon and five major planets and thus to show the precise time. Indian number systems, today’s ‘Arabic numerals’, the use of zero and decimal fractions, were all crucial to al-Khwarizmi’s new world. His work on algebra, called
The Book of Restoring and Balancing
, uses his tables for proofs in the older science of geometry. His particular specialities included quadratic equations, essential to modern computer science.

Add to al-Khwarizmi’s maths the comprehensive translation and study of Greek and Sanskrit sources, discoveries in astronomy, medicine, the natural sciences, engineering, water management and map-making, and you start to get a sense of how far ahead the Abbasid empire was. This was young Islam, open-eyed Islam, out and exploring new worlds, devout but fiercely practical and intellectually ambitious. Its perspective included sub-Saharan Africa, the coasts of India and the Red Sea, and even Russia. As the Abbasid achievement grew and matured a few Westerners, such as the Norman King of Sicily Roger II, were ready to learn from it. But the rising power of the papacy, casting around for a unifying cause, saw the Muslim caliphate as unspeakable polygamist heathens. It is hard to crusade against someone and learn from them at the same time. Had the rival Muslim world of al-Andalus not existed, much of this precious knowledge might not have arrived in Europe for centuries to come.

Though the overthrow of Spain’s Visigothic noblemen was lightning-fast, leaving Christian rulers penned into a tiny, wet, mountainous
corner of the north of the peninsula, the Muslim conquerors had never felt completely secure. The political history of al-Andalus, from the 700s through to the final defeat of Granada, the last toehold of Moorish Spain, in 1492, is as riven by dynastic quarrels, rebellions, invasions and spectacular overthrowings as any other part of Europe. From early on, threats from religious zealots from North Africa and from Viking raiders were often more serious than the challenges from the Christians in the north. And the tough Berber tribesmen who had made up much of the Arab-led army of conquest periodically rebelled, with some success.

The escapee Umayyad prince who founded the kingdom of al-Andalus, Abd al-Rahman, had arrived from North Africa with a small army to seize power. At Córdoba in 756 he declared himself ‘Amir’, or civil ruler. He dealt with rebel Abbasids by pickling their heads in salt and sending them back to Baghdad, which was apparently an effective declaration of independence. Abd al-Rahman I would rule for thirty-three years, dividing up the peninsula into manageable portions, forging a formidable army composed of slaves, many of them Christian, and establishing a gloriously beautiful capital at Córdoba. There his great mosque can still be seen, albeit with a Catholic wedding-cake-Gothic cathedral painfully inserted through its middle. Its world-famous forest of slim, cream- and pink-striped arches is a perfect stone metaphor for al-Andalus itself. The double arches mimic Roman building, particularly the aqueducts found all over Spain, but the effect is a memory of palm trees shimmering in a distant desert; oasis-classical. The mosque was built on top of a church, but Christians were given other sites for churches. And though the architecture is obviously ‘Muslim’ the mosaic decorations are by Byzantine craftsmen. A complicated conversation between rival faiths had begun.

For this exotic kingdom was the reverse of pure-bred. Much of the population remained Christian – though, because they had to pay a special poll-tax unless they converted, many did. Christians living peaceably under Muslim rule were called ‘Mozarabs’; those who converted, ‘Muwallads’. Some of the latter, feeling themselves disdainfully treated by Arabs, were prone to rebel, and there was a ferocious and very long-running Muwallad revolt under the charismatic bandit-king Ibn Marwan, who later converted back to Christianity. Jews were generally far better treated than in any Christian kingdom. Slaves could
rise through the grand royal bureaucracy of Córdoba and female Christians were taken as concubines so that, to make things more complicated still, some of the most powerful amirs looked more European than Arab, with reddish-fair hair and blue eyes.

This was a land of mingle and double-cross. Christian kingdoms would seek support from Muslim rulers in their own local feuds; and Muslims would ally with Christians. Even El Cid, the great Christian warrior-hero, fought for Muslim rulers from time to time, if the pay was good enough. The landscape of central and southern Spain, littered with Christian and Moorish castles, fortified walls and ruined keeps, demonstrates just what a wild frontier country this was; but it was a lot more complicated than just Catholics fighting against Islam.

At its finest, al-Andalus was a glittering rebuke to the meagre, muddy kingdoms of northern Europe. Córdoba became one of the largest cities in the world, with a vast library of more than four hundred thousand books at a time when even substantial Christian monasteries could boast only a few score. Under its greatest ruler, Abd al-Rahman III, it had hundreds of public bathhouses and excellent running-water facilities, while even the grandest Christians kings still stank. Under al-Hakam II it openly proposed itself as an intellectual rival to Abbasid Baghdad, importing experts, particularly in the use of the astrolabe, that beautiful and ingenious device used to read the angle of the sun, moon and visible stars and thus determine one’s position in longtitude. Invented by the Greeks, the astrolabe became a kind of simple universal computer for the Muslims, deployed for everything from astrology to architecture. When Muslim learning reached northern Europe, the astrolabe also became a symbol for the new natural science: Chaucer was among those who celebrated it in print.

Although al-Andalus was an independent kingdom, Muslim duties of Hajj and the eternal business of trade kept the two ends of the Mediterranean closely connected, and ensured Córdoba’s fame. Al-Rahman’s huge palaces and fortresses brought awed sightseeing embassies both from the Christian world – Paris, Rome and Constantinople – and from Cairo, Baghdad and Damascus. Córdoba’s streets were clean, stone-paved and lit at night, and its libraries contained some of the sharpest minds known at the time, there honing their mathematics, astrology, grammar and astronomy.

Later, when the caliphate fell and Muslim Spain broke into many rival mini-states, or
taifas
, the learning and the expertise remained. Though the most obvious remains today are the fortified walls and spectacular castle ruins which testify to centuries of shifting frontier and religious warfare, the greatest Arab imports included a proper understanding of aquaculture, drainage and waterwheels; and new crops from the Near East and India that made southern Spain bloom with aubergines, peaches, apricots, oranges, lemons, melons, pears, cotton, rice and even vineyards. Later still, at the time of the more austere Almohad dynasty which ended the chaotic
taifa
period after invading from the mountains of Berber Spain, al-Andalus could still boast some of the greatest thinkers in Europe. They included Ibn Rushd, or Averroës as the Christians called him, who was a judge and lawyer at Córdoba, the most important of the Muslim thinkers, and a specialist in Aristotle; and Moses Maimonides, a Jewish physician and philosopher and author of
Guide for the Perplexed
.

The great philosophical debate of the time, which shook the Muslim world, pitted radical thinkers against the religiously orthodox. It was spearheaded by the Persian Avicenna, who tried to reconcile faith with the rationalist Greek philosophy of Aristotle. Writing from the 1020s onward, he distinguished between a remote, eternal Creator on the one hand and a complex day-to-day world of cause and effect, which he felt could be investigated and understood on its own terms. He suggested that God had simply set up the world, then had largely left it to follow its course, under rules that mankind could discover.

This was an invitation to the curious and determined, but it depended upon a passive and remote version of God which was not that of orthodox Muslim thinkers: their God was deeply and busily engaged in the world. The most famous of these orthodox thinkers, al-Ghazali, writing in the later part of the eleventh century, lashed Avicenna in a book splendidly titled
The Incoherence of the Philosophers
. But he in turn was attacked by Averroës, who also distinguished between the world of eternity, outside time, which was where God existed, and the week-by-week, colourful, smelly world of cause and effect explained by Aristotle. Like Avicenna, he was creating a space for human reason and investigation – a bubble in which enlightenment could thrive inside a universe made by God. There could hardly be a more all-encompassing proposition for the world of the time. Only by
doing so could the probing, philosophizing inheritance of the Greeks, from that first age of reason, be revived in the Asia and Europe of Jewish, Christian and Muslim faiths. It was an invitation to think again, a battle-cry against passively leaving everything to God’s will. Averroës felt this as a personal challenge. It was a hot argument. One of his key works, hitting back at al-Ghazali, has an even better title:
The Incoherence of Incoherence
.

Averroës, though commissioned to think radically by an Andalusian caliph, pushed things so far that he was banished from Córdoba in 1195 and his writings were burned. But translated into Latin, and discovered later by Christians as they seized Muslim strongholds, they would hugely influence the West. The historian Jonathan Lyons says that he gave Europe ‘a thoroughly rationalist approach to philosophy that changed for ever the landscape of Western thought. This put Averroës almost five centuries ahead of Descartes . . . the West’s traditional candidate for founder of modern philosophy.’
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Alongside him were ranked Avicenna but also Moses Maimonides, the Jewish Andalusian who took a similarly radical and challenging view of the bubble space in which man could reason and argue. These are men who deserve to be as well known as Voltaire, Hume or Montesquieu.

The flow of Arab and Andalusian philosophy into the Christian world had been unleashed by the capture of Toledo from al-Andalus in 1085, revealing a hoard of books and manuscripts from Córdoba and Baghdad. Monks and translators followed. Scholars such as Oxford’s Duns Scotus brought Averroës and therefore Aristotle to a Christian audience. In Paris and Naples, the great Christian thinker Thomas Aquinas absorbed his style of argument and, while disagreeing about aspects of Aristotle, found the Andalusian a vital inspiration, one transmitted to Dante in Florence. These early Christian Aristotelians encountered just the same kind of resistance from popes and bishops as had Averroës and Maimonides from caliphs and imams. Islamic arguments about the nature of God and the scope for human reason to unlock nature were mirrored very closely, in early European universities, in debates between teachers and students at Paris, Bologna and Rome.