fit almost any political situation, and identified with kings and emperors, even popes, whether good or bad. All the signs could be made to fit. This tradition confronted the official Church with an almost insoluble problem. If it played things quietly, the millenarians would demand reform. But if the Church tried to initiate reform, as under Gregory Vil, this also was calculated to stir up the latent millenarian forces. The tradition of lay preaching had never been completely buried; laymen responded joyfully to efforts to improve the priesthood and tried to take the movement into their own hands. Much of the heterodox effervescence of the twelfth century was the indirect result of the Gregorian campaign. There were areas in the lower Rhineland, for instance, where forms of unorthodox revivalism coexisted with the official Church more or less throughout the Middle Ages. It is a mistake to believe everyone had his or her place in society. On the contrary: between the orderly guilds of the towns and the feudal hierarchy of the countryside there was an immense chaos teeming with the displaced, the dispossessed, the chronic sick or crippled, beggars, lepers, runaway serfs. Perhaps a third of the population did not fit into official categories, but formed the raw materials of huge crowds which formed and dispersed mysteriously and rapidly. Runaway monks or priests who had fallen out with the Church existed in plenty to provide leadership and half-knowledge. Once such a mob was on the march it was difficult to stop. In 1251, for instance, in response to the failure of the Fourth Crusade, a renegade Hungarian monk called Jakob preached an anti-clerical crusade and taught that the murderer of a priest gained merit. He gathered an army of thousands and rampaged through northern French towns. He was able to occupy places like Paris, Orleans and Amiens virtually without opposition, and loot the convents of the friars; in Tours he rounded up the Dominicans and Franciscans and had them whipped through the streets. Then he was murdered and his mob dispersed as quickly as it had collected. Almost any notable event could produce such outbreaks - the preaching of a crusade, a bad harvest, famine, industrial distress, defeat in battle, the failure of a promised miracle to occur. The authorities could do very little once a massmovement got started. Then they had to wait until the mob's excesses produced a popular reaction, at any rate among the bourgeoisie, or until a regular army could be collected. Hence the Inquisition served as an early-warning device; it probed and checked and winkled out trouble-makers before they could collect and unleash a mob. If it failed, then there might be no alternative but to launch an internal crusade. Thus hateful devices like the Inquisition, or the crusade against ‘heretics’, were seen by many - not just the rich, but anyone who liked stability-as indispensable defenses against social breakdown and mass terrorism . The Church and the secular establishment could not, however, tackle such phenomena at the root by destroying their basis of credulity. Was not the Church itself based on credulity? Kill belief, and where was the total Christian society? In any case, popes and kings could not escape from the intellectual environment they shared with every wild-eyed fanatic and millenarian fakir. Prophecy, on which such movements were based, was not only scripturally orthodox but scientifically respectable. Prophetical analysts were among the most learned men of their day, part of a tradition of wisdom which stretched from the Magi to Newton, and included virtually all the intellect uals in western society until the mid seventeenth century. It is no accident that the most influential of all the medieval inventors of prophetic systems, Joachim of Flora (died 1202), was also the most learned, systematic and ‘scientific. He was not a rebel but a fashionable Calabrian abbot, patronized by three popes, whose conversation delighted Richard the Lionheart on his way to the Third Crusade. He brought together all the various prophetic sources, pagan, Christian, biblical and astronomical, and examined them far more carefully than anyone else had done before. deducing from them his own future projections. The method was basically the same as Marxist historical determinism and had the same mesmeri c fascination. Joachim calculated that Antichrist would arise within the Church and hold high office - a new and riveting idea. On the basis of historical analysis and projection, he deduced that the last age’ would be enacted within history 85