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Liber III · Black & White Magic

Liber III · Black & White Magic · Chapter IV: Natural Magic

Roger Bacon and Magic: Books of Solomon and the Secrets of Nature

Roger Bacon and magic: how the Franciscan condemned the books of Solomon, defended astrology and the secrets of nature, and became a legendary magician.

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Roger Bacon (c. 1214/20–c. 1292), an English Franciscan philosopher, wrote some of the sharpest medieval criticism of magical books while himself acquiring a reputation as a magician. In the works he prepared for Pope Clement IV in 1267–70 he complained that books of magic circulated under the names of Solomon and other ancient sages, urged that they be examined and forbidden, and argued that true science, which he called the secrets of art and nature, could achieve wonders that magicians only pretended to perform.

Roger Bacon: Life and Learning§

Little is certain about Bacon's early life. He was born in England around 1214–1220, studied at Oxford and in the 1240s lectured on Aristotle's natural philosophy in the arts faculty at Paris, among the first to do so. Back in England he came under the influence of the circle of Robert Grosseteste, bishop of Lincoln, and turned to optics, languages, mathematics and the study of nature, spending heavily, by his own account, on books, instruments and assistants. Around 1257 he entered the Franciscan order.

His great opportunity came in 1266, when Guy Foulques, a cardinal who had heard of his ideas and had just become Pope Clement IV, asked him to send his writings, secretly and despite the order's restrictions on publication. Bacon responded with remarkable speed. The Opus maius, sent in 1267, was accompanied or followed by the Opus minus and the Opus tertium. Together they propose a reform of Christian learning in which languages, mathematics, optics, experimental science and moral philosophy serve theology and the defence of the Church. Clement died in 1268, and the programme had no official result.

A later Franciscan chronicle reports that Bacon was condemned by the minister general Jerome of Ascoli around 1277–79 for "suspected novelties" and imprisoned. The story is not confirmed by contemporary evidence and historians are divided over it. He was writing again by 1292, the probable year of his death in Oxford.

Mathematicians and Magicians in the Opus Maius§

Bacon's discussion of magic is woven into his defence of mathematics, the fourth part of the Opus maius. Church Fathers and canon law had condemned "mathematicians", and Bacon was anxious to show that the condemnation did not touch the true science. The ancient word, he argued, had been applied to magicians who practised divination and invoked spirits; genuine mathematicians, who studied number, geometry and the heavens, were blameless and useful.

He therefore separated judicial astrology, which he defended, from magic, which he rejected. Astrology, in his view, revealed how celestial bodies act on the elements and on human bodies; it could guide medicine, predict natural events and even illuminate the history of religions, whose rise and fall he associated with the great conjunctions of planets, an idea he took from Abu Ma'shar. He stressed, in line with Christian doctrine, that the heavens incline the body but do not compel the free will. The sciences he defended overlap with those catalogued at about the same time in the Speculum astronomiae, and with the respectable astrology outlined in astrology: a complete guide.

Magic, by contrast, he described as a set of practices relying on characters, incantations, conjurations and sacrifices. Its successes, where they were not tricks, depended on demons, who deceived those who called on them. Bacon's position here is that of most scholastic theologians, but he expressed it with unusual energy and from the point of view of someone who wished to save the natural sciences from suspicion.

Bacon on the Books of Solomon§

Bacon knew that the magical literature of his time circulated under venerable names. In the works for Clement IV he complained that many books of magic were ascribed to Solomon and to other famous authorities, falsely and to win them credit, and that these deserved to be prohibited. He did not, however, recommend that they simply be destroyed unread. Wise and trusted men, he suggested, should examine them, so that what was false and harmful could be identified and so that genuine knowledge mixed into them, or wrongly condemned alongside them, should not be lost.

This double attitude is characteristic. Bacon worried about two errors at once: the danger of necromancy disguised as philosophy, and the danger of ignorant critics condemning real science as magic. Some of the most valuable branches of learning, he observed, had been suspected precisely because the uneducated could not tell the difference. His comments are among the earliest Latin references to a magical literature of Solomon, alongside the lists in the Speculum astronomiae, and they show that texts of the kind later known as the Key of Solomon and the books of rings, seals and spirits were already circulating among learned readers in the 1260s. Their later history is traced in necromancy in the Middle Ages and what is Solomonic magic.

Bacon also held views that sat close to the boundary he defended. He believed that words uttered with deep intention, faith and desire, at astrologically fitting times, could carry a real natural force, and that the rational soul could affect bodies outside itself. Such ideas about the power of words and of the imagination, which he grounded in his theory of the multiplication of species, left later readers uncertain where his natural philosophy ended and magic began.

The Secret Works of Art and Nature and the Nullity of Magic§

The work most often cited in this connection is the Epistola de secretis operibus artis et naturae et de nullitate magiae, the "Letter on the Secret Works of Art and Nature and on the Nullity of Magic". It is generally attributed to Bacon, though its date is uncertain and its later chapters, which turn to cryptic alchemical recipes, may have been added or reworked.

The letter argues that much of what passes for magic is fraud: sleight of hand, ventriloquism, deception in the dark and the credulity of the audience. Charms and characters are worthless in themselves. True marvels come from art working with nature, and Bacon lists examples of what could be achieved: ships that move without rowers, carriages that run without animals, a flying machine in which a man turns an engine to beat artificial wings, devices for walking on the bed of the sea and bridges without supports. He also describes the wonders of optics, with mirrors and lenses that make distant things seem near, and he mentions an explosive powder used in a children's toy, one of the earliest European references to gunpowder.

Historians have often read these passages as prophecies of modern technology. More precisely, they belong to a medieval genre of natural wonders and to the idea, developed by contemporaries such as William of Auvergne, that the hidden powers of nature are real and can be put to work without demons. In that sense Bacon is an important figure in the history of natural magic, even though he did not use the term approvingly. His interest in the pseudo-Aristotelian Secretum secretorum and in the prolongation of life through alchemy belongs to the same outlook.

Friar Bacon the Necromancer: The Legend§

Within a few centuries the critic of magic had become a magician. Bacon's learning, his interest in optics and alchemy, the obscurity of his later life and the story of his imprisonment encouraged legends. Alchemical treatises such as the Speculum alchemiae circulated under his name, and he was counted among the great medieval adepts of the philosophers' stone.

In Elizabethan England the legend reached its fullest form. A prose romance, The Famous Historie of Fryer Bacon, and Robert Greene's play Friar Bacon and Friar Bungay (written around 1589 and printed in 1594) present him as a conjuror who contests with German magicians and makes a brazen head that would speak and teach him to wall England with brass. In Greene's play the head speaks only "Time is", "Time was" and "Time is past" while Bacon sleeps, and then shatters. The episode parallels legends told of Albertus Magnus and Pope Sylvester II.

The legend had a modern echo. In the early twentieth century the bookseller Wilfrid Voynich attributed the enigmatic manuscript now named after him to Bacon, and William Newbold claimed in 1921 to have deciphered it as Bacon's work. The decipherment was refuted, and radiocarbon dating has since placed the manuscript's vellum in the early fifteenth century.

Bacon's Place in the History of Magic§

Bacon's significance for the history of magic lies in the clarity with which he drew the line between permitted and forbidden knowledge, and in the way his own reputation crossed that line after his death. His criticism of the books of Solomon is valuable evidence for the spread of Latin ritual magic in the thirteenth century; his defence of astrology and natural wonders helped shape the space later occupied by Renaissance natural magic; and his legend shows how readily a learned friar could be imagined as a necromancer. Modern scholarship, from Lynn Thorndike's surveys to the studies collected by Jeremiah Hackett and the work of Amanda Power on his religious purposes, has largely restored the Franciscan reformer behind the conjuror.

Frequently asked questions§

Was Roger Bacon a magician?§

No evidence shows that Bacon practised ritual magic. He condemned magical books and demonic arts, while defending astrology, alchemy and the study of nature's hidden powers. His reputation as a magician grew after his death and was popularised in Elizabethan legend and drama.

What did Roger Bacon say about the books of Solomon?§

In his writings for Pope Clement IV in 1267–70 he complained that many magical books were falsely attributed to Solomon and other authorities and should be prohibited. He advised that learned men examine them so that genuine knowledge would not be condemned along with them.

What is the brazen head of Friar Bacon?§

It is a legendary bronze head that Bacon was said to have made so that it would speak and impart wisdom. In Robert Greene's play the head speaks three short phrases while Bacon is asleep and then breaks, so that his labour is wasted.

Did Roger Bacon write the Voynich manuscript?§

No. The attribution was proposed in the early twentieth century and supported by a claimed decipherment that was later disproved. Radiocarbon dating places the manuscript's vellum in the early fifteenth century, long after Bacon's death.

Sources and further reading§