. The terms magica and ars magica were used in medieval Europe primarily for operations that explicitly or implicitly invoked the aid of demons. In the late Middle Ages, a second type of magic, “natural magic,” came to be recognized, which relied instead on “occult virtues” within nature; these virtues were inherent in certain herbs, gems, animals, or verbal formulae and could be exploited by those who knew the effects they could produce. While these latinized Greek terms were used chiefly by those with formal education, vernacular words, such as sorcellerie, partly overlapped with them in their significance, although the vernacular terms usually referred more unambiguously to maleficent forms of magic.
Magical formulae occur in some medieval medical writings. Magic remedies of antiquity were passed down to the Middle Ages in such writings as the De medicamentis liber of Marcellus Empiricus of Bordeaux (ca. 400), a collection of medical experimenta. The author’s epithet derives from his concern not to ground his work in medical theory but merely to list formulae that he or others have found effective. His materia medica includes a wide range of objects with occult virtues: herbs, gems (sometimes enhanced with magical characters), and the bodily parts of animals (bat’s blood, mouse’s brain, wolf’s liver). He tells how a person who has gone bald from bewitchment can restore his hair by rubbing the bald spot with rough linen, then applying a compound of ashes from a lizard, purple wool, and paper, mixed with oil, but in this case the affliction is more obviously magical than the cure. Elsewhere, he recommends procedures for transferring disease to animals; a person suffering from toothache, for example, should spit into the mouth of a frog and implore the frog to assume the toothache. Alternatively, a toothache may be cured by reciting the incantation Argidam, margidam, sturgidam seven times under a waning moon, on Tuesday and Thursday. Some of his prescriptions involve ritual observances: the goat’s blood collected to treat a stone should be collected by naked boys, and the person who kills the goat must be chaste.
While Marcellus’s work is only partly magical in character, and of interest mainly for its illustrative value, Marbode of Rennes’s Liber lapidum seu de gemmis was a specifically magical compilation of considerable importance, which remained for generations an influential source of information on the occult properties of gems. Marbode probably composed the work in the late 11th century, before becoming bishop of Rennes. He wrote in Latin hexameters, intending his work for a small circle of friends. (Further publication would defile the mysteries: Nam majestatem minuit qui mystica vulgat.) Marbode admitted that herbs have great power, but the virtues of gems are greater. Some people may question their powers, but only because powerless imitation gems have misled them. The sapphire, for example, preserves a person from fraud, envy, and terror and can release a captive from prison. An amulet made of gagates (“jet”) works against dropsy, while fumigation with this stone is effective against both epilepsy and demons. Indeed, gagates can even counteract magical illusions and incantations. Magnetite, which Circe used in praestigiis magicis, can be used to test the fidelity of one’s wife: place it against her head while she is sleeping, and if she has been chaste she will embrace you, while if she has committed adultery she will tumble from the bed. A burglar can force all occupants from a house by sprinkling burning coals on the floor and then adding crushed magnetite.
Through the 12th century, medieval writers relied heavily on Isidore of Seville’s Etymologiae for discussion of magic and its various forms: Rabanus Maurus (in his De magicis artibus), Hincmar of Reims, John of Salisbury, and others drew from Isidore, and the survey of magic at the end of Hugh of Saint-Victor’s Didascalicon stands in this tradition of antimagical literature. Hugh says that magic is “false in what it professes, mistress of every iniquity and malice, lying about the truth and truly harming souls, seduces them from divine religion, promoting the worship of demons, encouraging the corruption of morals, and impelling its followers’ minds to every crime and wickedness.” He then goes on to divide magic into its branches: mantice includes necromancy and divination by the four elements, mathematica is the use of horoscopes and other divinatory devices, sortilegium is casting of lots, maleficium uses demonic incantations and ligatures ostensibly for healing, and praestigium deceives the senses by demonic art.
Perhaps the most important theorist of magic in medieval France was William of Auvergne, a theologian and then (from 1228 to 1249) bishop of Paris, who discusses magic extensively, especially in De universo 2.3.18–25, and De fide et legibus 24 and 27. William presents himself as a pioneer in this area, claiming with slight exaggeration that he has found nothing relevant in earlier writers. What surely is true is that he is the first important theorist in the high Middle Ages to articulate a conception of magic allowing for natural as well as demonic forms. He is also important because in his early years he read widely in the writings of the magicians and astrologers themselves and thus had a clear idea what they were attempting to do.
Like other writers, William recognizes that a great deal of magic is demonic. He tells of one necromantic experiment entitled the Major Circle, in which demon kinds from the four cardinal directions come with retinues of horsemen, musicians, jugglers, and so forth. Another such experiment produces a phantom castle. The magicians may claim they are invoking good spirits, but William is convinced that the angels used are fallen ones, demons who live in the sublunary air and in desert regions (to which magicians often have recourse). He tells how magicians have young boys gaze into mirrors or other reflective surfaces, and after conjurations have been recited some such mediums (perhaps as few as one out of ten) will see apparitions. Plato explained this effect in terms of the soul being turned back on itself so that its own power of divination is enhanced, and William conceded that explanations of this sort were possible, yet he inclined to suppose that demons were generally at work in such magic.
William is more original in recognizing a natural magic—“the part of natural science that is called natural magic” (De universo 2.3.21) as an alternative to the demonic sort. Natural magic works with materials rare in Europe but common in and around India. Some substances, however, are presumably available domestically. Magicians kill animals when they are in heat, for example, hoping to extract powerful love potions from their bodies. William cites Pliny’s example of the fish called echineis or remora that can cause a ship to cease moving, and he tells how the gem and herb called heliotrope can make a person invisible. He includes under the heading of natural magic what he calls the sensus naturae, which corresponds roughly to extrasensory perception (by which a woman can detect her beloved when he is two miles away, or a dog can identify a thief amid a crowd).
William holds that natural magic is in itself harmless; indeed, God should be glorified for such wonders. Yet it can be used for illicit ends, and in early Christianity it was condemned because it seemed to involve the work of gods and thus led people into idolatry. More fundamentally, he holds that many techniques ascribed to natural magic cannot in fact work unless demons intervene: images, characters, and incantations have no effect in themselves, and if they have efficacy it is only as signals to demons. Words can work only by means of their material (air), their form (sound), or their signification, and William discounts all these possible explanations for the natural efficacy of incantations; air, for example, can kill people only if it is infected with venom from toads, dragons, or plague. (He does grant that names of God seem to have exceptional efficacy, although he says the magicians use a corrupt substitute for the Tetragrammaton.)
Furthermore, William disputes many claims about magic and says that if magic were as powerful as some have claimed any magician could hold the world at his mercy. Yet his skepticism is at times tempered by recollection of the wonders natural magic can accomplish. He doubts that mercury is effective against demons and incantations, until he recalls that a crab suspended in the air deters underground moles and that peony expels demons from possessed people.
Yet many of the pretended accomplishments of magic are mere trickery, exemplified by the use of magic candles that can make a house appear to be filled with serpents, and by illusions comparable with fantastic dreams. Demons often use trickery, as well as the occult powers in nature, in aiding magicians; thus, the demonic entourage produced by “Major Circle” is merely an illusion, seen only by those inside the magic circle, and the horses that appear leave no hoofprints. Practitioners of natural magic sometimes also deceive people with mere illusions.
Thomas Aquinas discussed magic in various places but most importantly in Summa contra gentiles 3.101–05. He tells how magicians make use of herbs and other objects, verbal formulae, figures and characters, images, sacrifices, and astrological observations to discover hidden treasure, foretell the future, open doors, become invisible. Yet he believes the means employed are not a sufficient cause for the effects attained, which require the intervention of demons. The magicians are typically criminal persons using these arts to perform such offenses as adultery, theft, and murder. Elsewhere, however, Thomas deals with the occult virtues in nature in a way that is less hostile and examines the ways in which astral influences can underlie such virtues. While he does not speak of the use of these occult virtues as “natural magic,” as other writers did, he manifests an interest in such phenomena and a willingness to acknowledge that many extraordinary effects could be accomplished by means within the natural order.
Nicole Oresme’s writings on magic illustrate one possible stance that a late-medieval philosopher and scientist might adopt. Oresme wrote about magic in his treatise De configurationibus qualitatum et motuum, in a treatise of 1370 devoted chiefly to astrology, and in a series of Quodlibeta on the wonders of nature appended to the treatise of 1370.
Much of the effect of magic he attributes to deception and self-delusion. Yet certain types of magic can have real effect: sometimes, it influences the spirits and senses of the beholder but at other times affects external objects directly. It does so by means of virtues inherent in the magicians’ herbs, gems, incantations, and other such means. Unlike such writers as Marsilio Ficino, Oresme does not attribute such magical virtues to the accumulated influence of the stars; instead, he attributes them to the “configuration,” or physical qualities, of the objects and formulae used. If incantations have real magical effect, it is because the physical quality of the sound, both the words and the melodies, produces these extraordinary results. Unlike Avicenna and Algazel, he did not acknowledge the direct power of mind over matter, but he did acknowledge the indirect power of the mind: the imagination may be so distorted that it affects the body, which in turn has influence on the air and on other bodies around it. The eye in particular serves as a medium for the transmission of corrupt influences from the imagination, and this effect works most powerfully when a physically and mentally corrupt old woman casts an evil eye on the tender body of an infant.
Oresme is generally skeptical about demonic magic, which he calls nigromantia. Here, too, deception and self-delusion play an important role. Nigromancers (or necromancers) commonly use impressionable young boys as mediums; they make these boys stare into polished surfaces in hopes that they will see demons, and often the apparitions cause the mediums to go blind. The nigromancers themselves often show facial distortion and mental alienation during their invocations; they prepare them-selves with fasting, and they operate by preference at night, thus encouraging disturbance of body and mind and predisposing the imagination toward delusion. Demonic apparitions may also be caused by melancholy. Repeatedly, following his 13th-century predecessor Witelo, Oresme insisted on finding natural rather than demonic explanations for observed wonders, adding in explanation that “it is better to say this than to ascribe [the effect] to demons.” He was aware that Alkindi and Algazel denied that any magic was the work of demons, ascribing it instead to a kind of natural radiation, or to the imaginative powers and virtues of the soul. Yet Oresme himself did not take this extreme position. Even if grudgingly, he admitted that certain effects of magic are so unnatural that they can only be the work of malign or benign spirits. Magicians may succeed in invoking demons. They do not coerce demons; if demons come, it is only with God’s permission and with the intention of deceiving their invokers. Magicians’ incantations may allure or repel demons, as David’s playing on the harp relieved Saul by dispelling demons.
Oresme seems to have interviewed some people who claimed to have magical powers. He tells how he received permission to speak with an accused sorceress, whom he found terrified to the point of incoherence. Again, he tells how certain incantations that magicians perform have never succeeded when he was present. And when he argues that no one can meddle in these arts without incurring some evil, he appeals not only to authority and reason but also to experience.
Marcellus. De medicamentis liber, ed. Georg Helmreich. Leipzig: Teubner, 1889.
William of Auvergne. Guilielmus Alvernus: Opera omnia. Paris: Andraeas Pralard [?], 1674.
Flint, Valerie I.J. The Rise of Magic in Early Medieval Europe. Princeton: Princeton University Press, 1991.
Hansen, Bert. Nicole Oresme and the Marvels of Nature. Toronto: Pontifical Institute of Mediaeval Studies, 1985.
Kieckhefer, Richard. Magic in the Middle Ages. Cambridge: Cambridge University Press, 1989.
Peters, Edward. The Magician, the Witch, and the Law. Philadelphia: University of Pennsylvania Press, 1978.
Riddle, John M. Marbode of Rennes’ (1035–1123) “De lapidibus” Considered as a Medical Treatise, with Text, Commentary and C.W.King’s Translation, Together with Text and Translation of Marbode’s Minor Works on Stones. Wiesbaden: Steiner, 1977.
Thorndike, Lynn. The History of Magic and Experimental Science. 2 vols. New York: Macmillan and Columbia University Press, 1923–58.
This is the complete article, containing 2,406 words
(approx. 8 pages at 300 words per page).
