When Gregory gave his mandate to Conrad of Marburg and other inquisitors, he could do so in the full confidence that persecution worked. Innocent’s surgery on the diseased body of Christendom had manifestly been a success. The enemies of Christ were everywhere in retreat. In Spain, below the Sierra Morena, the great mountain range that stretches across the south of the Iberian peninsula, God’s favour had granted Christian arms a decisive victory. The Saracens’ defeat at Las Navas de Tolosa in the summer of 1212 had left them fatally exposed. Two decades on, their greatest cities – Cordoba, Seville – stood on the brink of capture by the king of Castile. Meanwhile, in the heartlands of the Albigensians, those among the good men who had survived the exterminating zeal of the crusaders were fugitives, skulking in forests and cattle-sheds, their days of haranguing bishops in village squares gone for good. To Gregory, and to many others, it seemed evident that a great conspiracy had been defeated. Before their defeat at Las Navas de Tolosa, the Saracens were reported to have been plotting to march to the rescue of the Albigensians. The Albigensians themselves – now that the good men were broken, and the reality of what they had been distorted for good – were increasingly seen as the agents of an entire heretical church. This church was said to have existed since ancient times; to have derived from Bulgaria; to span the world. Scholars knowledgeable in the heresies of antiquity traced its ultimate origins to a prophet in Persia. ‘They follow him in believing that there are two sources of life: one a good god and the other an evil god – in other words, the Devil.’30
Such was the measure of the crusaders’ victory: that ghosts summoned from the unimaginably distant age of Darius would come to have a more vivid presence in the imaginings of the Christian people than those of the good men and good women themselves. The fantasy that the Albigensians had belonged to an ancient church consecrated to a belief in rival principles of good and evil – a church that in time would be given the name of ‘Cathar’ – would prove a particularly vivid one; but it was no less of a fantasy for that. The readiness of Gregory IX to sanction a belief in satanic conspiracies was nurtured by the blood of those who had perished in the Albigensian crusade. The slaughter had demonstrated that a diseased limb might indeed be amputated from the body of Christendom – but it had shown as well just how hard it could be to distinguish rottenness from solidity, dark from light, heretic from Christian.
The dread of this realisation – and of what it might mean for those entrusted by God with the defence of his people – would not rapidly go away.
The Eternal Jew
Shortly before the great victory of Las Navas de Tolosa, another Christian army, preparing for battle against the Saracens on the Portuguese coast, had seen riding in their vanguard a force of angelic horsemen. ‘Clad in white, they had worn red crosses upon their sur-coats.’31 The sense of Spain as a great battlefield between good and evil, between the heavenly and the infernal, had a long heritage in Christendom. The reconquest of lands lost to the Saracens had been tracked by the leaders of reformatio with an obsessive interest. It had literally helped to build Cluny. The abbey’s church, the largest in the world, had been paid for with the loot of al-Andalus. In 1142, its great abbot, Peter the Venerable, had crossed the Pyrenees, the better to understand what the Saracens actually believed. Meeting with scholars fluent in Arabic, he had employed them on a momentous project: the first translation of the Qur’an into Latin. Better persuasion than compulsion – such had always been Peter’s motto. Sure enough, the translation delivered, he had addressed the Saracens directly, ‘not as our men often do, with arms, but with words, not with violence but reason, not with hate but love’.32 Yet these emollient sentiments had not prevented Peter from feeling thoroughly appalled by the Qur’an. No more monstrous a compound of heresies, confected as it was ‘from both Jewish fables and heretical teachers’,33 could possibly have been imagined. Even its vision of heaven blended gourman-dising with sex. Cluny it was not. Far from building bridges, Peter’s translation of the Qur’an had only confirmed Christians in their darkest suspicions of its contents. Islam was the sump of all heresies, and Muhammad ‘the foulest of men’.34
The Qur’an, though, was not the only book to have been plundered from Saracen libraries. In 1085, Toledo, the ancient capital of the Visigothic monarchy and a celebrated centre of learning, had fallen to the king of Castile, the greatest of the various Spanish realms. Within only a few decades, a vast team of translators had been assembled by the city’s archbishop: Muslims, Jews, monks from Cluny. They had much to keep them busy. As well as texts by Muslim and Jewish scholars, Toledo had a treasure trove of Greek classics, works by ancient mathematicians, doctors, philosophers. These, although long available in Arabic translation, had been lost to the Latin West for many centuries. One author in particular was the focus of Christian obsession. ‘Only two books by Aristotle are still known to the use of the Latins.’35 So Abelard, shortly before 1120, had lamented. Within a decade, his complaint was out of date. Iacopo, a Venetian cleric long resident in Constantinople, had embarked on an astonishing labour that would see, by the time of his death in 1147, various works by Aristotle translated directly from Greek.* To this stream of translation the efforts of the school in Toledo had soon added a flood. By 1200, almost all of Aristotle’s known works were available in Latin. University teachers committed to the proposition that God’s creation was governed by rules, and that reason might enable mortals to comprehend them, fell on the writings of antiquity’s most renowned philosopher with a mixture of avidity and relief. That an authority such as Aristotle had been given voice again promised to set their own investigations into the functioning of the universe on a more rigorous footing than ever before. Paris in particular had fast become a hotbed of Aristotelian study. The sense of excitement generated by its schools had attracted students from across Christendom. Among them had been two future popes: Innocent III and Gregory IX.
Yet the resurrection of a sage who had lived long before Christ, nor had any familiarity with scripture, presented challenges as well as opportunities. If numerous aspects of his teaching – the fixity of species, or the unchanging motion of sun, and moon, and stars as they revolved around the earth – could readily be integrated into the fabric of Christian teaching, then others were more problematic. The very notion of a rationally ordered cosmos, so appealing to natural philosophers, continued to unsettle many in the Church. Aristotle’s insistence that there had been no creation, that the universe had always existed and always would, was a particularly glaring contradiction of Christian scripture. How, then, when crusaders were struggling to cleanse southern France of heresy, could students in the kingdom’s capital possibly be permitted to study such a noxious doctrine? Anxieties in Paris were heightened by the discovery in 1210 of various heretics whose reading of Aristotle had led them to believe that there was no life after death. The reaction of the city’s bishop was swift. Ten of the heretics were burned at the stake. Various commentaries on Aristotle were burned as well. Aristotle’s own books on natural philosophy were formally proscribed. ‘They are not to be read at Paris either publicly or in private.’36
But the ban failed to hold. In 1231, Gregory IX issued a decree that guaranteed the university effective independence from the interference of bishops, and by 1255 all of Aristotle’s texts were back on the curriculum. The people best qualified to learn from them, it turned out, were not heretics, but inquisitors. The days of annihilating entire towns on the grounds that God would know his own were over. The responsibility for rooting out heresy had now been entrusted to friars. Taking the lead was an order that had been established by papal decree back in 1216, to provide the Church with a shock force of intellectuals. Its founder, a Spaniard by the name of Dominic, had toured where the good men were to be found, matching them in all their austerities, and harrying them in debate. In 1207, two years before the annihilation of Béziers, he had met with a good man just north of the city, and argued publicly with him for over a week. To friars schooled in this tradition of militant preaching, Aristotle had come as a godsend. The obligation of the Dominicans was to question, to investigate, to evaluate evidence. Who better to serve as a model for this approach than history’s most famous philosopher? Aristotle, far from lending succour to the enemies of the Church, was successfully summoned to its defence. Institutionalised by the universities, and licensed by the papacy, the study of his philosophy was made ever safer for Christian scholars. If the standard of investigation into heresy benefited from this trend, then so too did investigation into the workings of the universe. To fathom these workings was to fathom the very ordinances of God.