The Growth of Knowledge



THE two centuries whose European history has been so hastily sketched in the preceding chapters were still part of what tradition calls the Middle Ages—which we may loosely define as the life of Europe between Constantine and Columbus, 325 to 1492 A.D. AS we summarize now the science, pedagogy, and philosophy of Western Europe in the fourteenth and fifteenth centuries, we must remind ourselves that rational studies had to fight for soil and air in a jungle of superstition, intolerance, and fear. Amid famines, plagues, and wars, in the chaos of a fugitive or divided papacy, men and women sought in occult forces some explanation for the unintelligible miseries of mankind, some magical power to control events, some mystical escape from a harsh reality; and the life of reason moved precariously in a milieu of sorcery, witchcraft, necromancy, palmistry, phrenology, numerology, divination, portents, prophecies, dream interpretations, fateful stellar conjunctions, chemical transmutations, miraculous cures, and occult powers in animals, minerals, and plants. All these marvels remain deathless with us today, and one or another wins from almost every one of us some open or secret allegiance; but their present influence in Europe falls far short of their medieval sway.

The stars were studied not only to guide navigation and date religious festivals, but also to forecast terrestrial occurrences and personal destinies. The pervasive influences of climate and season, the relation of tides to the moon, the lunar periodicity of women, and the dependence of agriculture upon the modes and moods of the sky, seemed to justify the claims of astrology that the heavens of today forecast the events of tomorrow. Such predictions were regularly published (as now), and reached a wide and avid audience. Princes dared not begin a campaign, a battle, a journey, or a building without assurance from the astrologers that the stars were in a propitious configuration. Henry V of England kept his own astrolabe to chart the sky, and when his queen was lying-in he cast his own horoscope of the child.1 Astrologers were as welcome as humanists at Matthias Corvinus’s enlightened court.

The stars, men believed, were guided by angels, and the air was congested with invisible spirits, some from heaven, some from hell. Demons lurked everywhere, especially in one’s bed; to them some men ascribed their night losses, some women their untimely pregnancies; and theologians agreed that such infernal concubines were real.2 At every turn, at any moment, the credulous individual could step out of the sense world into a realm of magic beings and powers. Every natural object had supernatural qualities. Books of magic were among the “best sellers” of the day. The bishop of Cahors was tortured, scourged, and burned at the stake (1317) after confessing that he had burned a wax image of Pope John XXII in the hope that the original, as the magic art promised, would suffer like the effigy.3 People believed that a wafer consecrated by a priest would, if pricked, bleed with the blood of Christ.

The repute of the alchemists had declined, but their honest research and glittering chicanery went on. While royal and papal edicts denounced them, they persuaded some kings that alchemy might replenish exhausted treasuries, and simple people swallowed “potable gold” 4 guaranteed to cure anything but gullibility. (Gold is still taken by patients and physicians in treating arthritis.)

The science of medicine contended at every step with astrology, theology, and quackery. Nearly all physicians related the prognosis of a disease to the constellation under which the sufferer had been born or taken ill; so the great surgeon Guy de Chauliac could write (1363), “If anyone is wounded in the neck while the moon is in Taurus, the affliction will be dangerous.” 5 One of the earliest printed documents was a calendar published at Mainz (1462) indicating the astrologically best times for bloodletting. Epidemics were widely ascribed to unlucky associations of the stars. Probably through disillusionment with medicine, millions of Christians turned to faith healing. Thousands came to the kings of France or England to be cured of scrofula by a touch of the royal hand. Apparently the custom had begun with Louis IX, whose saintliness led to the belief that he could work miracles. His power was supposed to have gone down to his successors, and, through Isabella of Valois, mother of Edward III, to the rulers of England. More thousands made pilgrimages to curative shrines, and turned some saints into medical specialists; so a chapel of St. Vitus was frequented by sufferers from chorea, since that saint was believed to be a specific for this disease. The tomb of Pierre de Luxembourg, a cardinal who at eighteen died of ascetic austerities, became a favorite goal, where, within fifteen months after his death, 1,964 cures were ascribed to the magic efficacy of his bones.6; Quacks flourished, but the law began to hamper them. In 1382 Roger Clerk, who had pretended to cure disease by applying charms, was condemned to ride through London with urinals hanging from his neck.7

Most Europeans believed in sorcery—i.e., the power of persons to control evil spirits and secure their help. The Dark Ages had been comparatively enlightened in this respect: Saints Boniface and Agobard denounced the belief in sorcery as sinful and ridiculous; Charlemagne made it a capital crime to execute anyone on a charge of witchcraft; and Pope Gregory VII Hildebrand forbade inquisition to be made for sorcerers as the cause of storms or plagues.8 But the emphasis laid by preachers upon the reality of hell and the wiles of Satan strengthened popular belief in the ubiquitous and iniquitous presence of himself or one of his company; and many a diseased mind or desperate soul harbored the idea of summoning such devils to its aid. Accusations of sorcery were made against a great variety of people, including Pope Boniface VIII. In 1315 the aristocrat Enguerrand de Marigny was hanged for sorcery, and in 1317 Pope John XXII ordered the execution of various obscure persons for plotting to kill him by invoking the assistance of demons. John repeatedly denounced the appeal to demons, ordered prosecutions for it, and prescribed penalties; but his edicts were interpreted by the people as confirming their belief in the existence and availability of demonic powers. After 1320 the indictments for sorcery multiplied, and many of the accused were hanged or burned at the stake. It was a common opinion in France that Charles VI had been made insane by magic means; two sorcerers were engaged who promised to restore his wits; when they failed they were beheaded (1397). In 1398 the theological faculty of the University of Paris issued twenty-eight articles condemning sorcery, but assuming its occasional efficacy. Chancellor Gerson pronounced it a heresy to question the existence or activity of demons.9

Witchcraft was the practice of sorcery by persons who were alleged to worship Satan, in nocturnal assemblies or “Sabbaths,” as the master of the demons whom they affected to employ. According to popular belief the witches, usually women, secured supernatural powers at the price of this devil-worship. So commissioned, they were supposed to override natural laws, and to bring misfortune or death to whom they wished. Scholars like Erasmus and Thomas More accepted the reality of witchcraft; some priests in Cologne doubted it; the University of Cologne affirmed it.10 Most churchmen claimed—and lay historians in some measure agree—that the secret gatherings by night were excuses for promiscuous sexual relations, and for initiating young people into the arts of debauchery.11 Whether through insane delusion, or to secure release from torture, many witches allegedly confessed to one or another of the evil practices charged to them. It may be that these “witches’ Sabbaths” served as a moratorium on a burdensome Christianity, and as a partly playful, partly rebellious worship of Satan as the powerful enemy of a God who condemned so many pleasures to repression and so many souls to hell; or these clandestine rites may have recalled and reaffirmed pagan cults and feasts of the deities of earth and field and forest, of procreation and fertility, of Bacchus, Priapus, Ceres, and Flora.

Secular and episcopal courts joined in efforts to suppress what seemed to them the most blasphemous depravity. Several popes—in 1374, 1409, 1437, 1451, and especially Innocent VIII in 1484—commissioned agents of the Inquisition to deal with witches as abandoned heretics, whose sins and machinations blighted the fruit of fields and wombs, and whose pretensions might seduce whole communities into demonolatry. The popes took literally a passage in Exodus (22 :18): “Thou shalt not suffer a witch to live.” Nevertheless the ecclesiastical courts, before 1446, contented themselves with mild penalties, unless a pardoned offender relapsed. In 1446 the Inquisition burned several witches at Heidelberg; in 1460 it burned twelve men and women at Arras; and the name V audois given them, as generally to heretics (Waldenses) and witches in France, survived an Atlantic voyage to generate the word Voodooism for Negro sorcery in the French colonies of America.12 In 1487 the Dominican inquisitor Jacob Sprenger, honestly frightened by the apparent spread of sorcery, published an official guide for the detection of witches, Malleus maleficarum (Hammer of Witches). Maximilian I, then King of the Romans, prefaced with a letter of warm recommendation this “most portentous monument of superstition which the world has produced.” 13 These maleficent women, said Sprenger, by stirring up some devilish brew in a caldron, or by other means, can summon swarms of locusts and caterpillars to devour a harvest; they can make men impotent and women barren; they can dry up a woman’s milk, or bring abortion; by a look alone they can cause love or hatred, sickness or death. Some of them kidnap children, roast them, and eat them. They can see things at a distance, and foresee the weather; they can transform themselves, and others, into beasts.14 Sprenger wondered why there were more female than male witches, and concluded that it was because women were more lightheaded and sensual than men; besides, he added, they had always been favorite instruments of Satan.15 He burned forty-eight of them in five years. From his time onward the ecclesiastical attack upon witchcraft was intensified until it reached its full fury in the sixteenth century, under Catholic and Protestant auspices alike; in this type of fearful ferocity the Middle Ages were outdone by modern times. In 1554 an officer of the Inquisition boasted that in the preceding 150 years the Holy Office had burned at least 30,000 witches, who, if they had been left unpunished, would have brought the whole world to destruction.16

Many books were written in this age against superstition, and all contained superstitions.17 Agostino Trionfo addressed to Pope Clement V a treatise advising him to outlaw occult practices, but Trionfo held it unpardonable in a physician to perform a phlebotomy during certain phases of the moon.18 Pope John XXII issued powerful blasts against alchemy (1317) and magic (1327); he mourned what he thought was the increasing prevalence of sacrifices to demons, pacts with the Devil, and the making of images, rings, and potions for magical purposes; he pronounced ipso facto excommunication upon all practitioners of such arts; but even he implied a belief in their possible efficacy.19

The great antagonist of astrology in this age was Nicole Oresme, who died as bishop of Lisieux in 1382. He laughed at astrologers who could not predict the sex of an unborn child but, after its birth, professed to foretell its earthly fate; such horoscopes, said Oresme, are old wives’ tales. Repeating the title and effort of Cicero fourteen centuries back, he wrote De divinatione against the claims of soothsayers, dream interpreters, and the like. Amid his general skepticism of the occult he admitted that some events could be explained as the work of demons or angels. He accepted the notion of the “evil eye”; he thought that a criminal would darken a mirror by looking into it, and that the glance of a lynx could penetrate a wall. He acknowledged the miracles of the Bible, but he repudiated supernatural explanations where natural causes sufficed. Many people, said Nicole, are credulous of magic because they lack acquaintance with natural causes and processes. They accept on hearsay what they have not seen, and so legend—as of a magician climbing a rope thrown into the air—may become a popular belief.20 (This is the oldest-known mention of the rope-climbing myth.) Consequently, Oresme argued, the wide prevalence of a belief is no proof of its truth. Even if many persons claim to have witnessed an event contrary to our ordinary experience of nature, we should hesitate to believe them. Moreover, the senses are so easily deceived! The color, shape, and sound of objects vary with distance, light, and the condition of the sensory organs; an object at rest may seem to be moving, and one in motion may seem at rest; a coin at the bottom of a vase filled with water appears more remote than one so placed in an empty vase. Sensations must be interpreted by judgment, and this too may err. These deceptions of senses and judgment, says Oresme, explain many of the marvels ascribed to supernatural or magical powers.21

Despite such brave advances toward a scientific spirit, the old superstitions survived, or merely changed their form. Nor were they confined to the populace. Edward III of England paid a great sum for a phial which, he was assured, had belonged to St. Peter. Charles V of France was shown, in Sainte Chapelle, a phial allegedly containing some of Christ’s blood; he asked his savants and theologians whether this could be true; they answered cautiously in the affirmative.22 It was in this atmosphere that education, science, medicine, and philosophy struggled to grow.

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