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.
Richard Kieckhefer
The Encyclopedia 1091