Cover image for The Transformations of Magic: Illicit Learned Magic in the Later Middle Ages and Renaissance By Frank Klaassen

The Transformations of Magic

Illicit Learned Magic in the Later Middle Ages and Renaissance

Frank Klaassen


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ISBN: 978-0-271-05626-5

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ISBN: 978-0-271-05627-2

280 pages
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Magic in History

The Transformations of Magic

Illicit Learned Magic in the Later Middle Ages and Renaissance

Frank Klaassen

“Well argued and well researched, [The Transformations of Magic] represents a thorough and scholarly treatment of medieval magical texts, as well as an engrossing read.”


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Frank Klaassen was selected as the recipient of the 2014 Margaret Wade Labarge Prize for The Transformations of Magic.

In this original, provocative, well-reasoned, and thoroughly documented book, Frank Klaassen proposes that two principal genres of illicit learned magic occur in late medieval manuscripts: image magic, which could be interpreted and justified in scholastic terms, and ritual magic (in its extreme form, overt necromancy), which could not. Image magic tended to be recopied faithfully; ritual magic tended to be adapted and reworked. These two forms of magic did not usually become intermingled in the manuscripts, but were presented separately. While image magic was often copied in the fourteenth and fifteenth centuries, The Transformations of Magic demonstrates that interest in it as an independent genre declined precipitously around 1500. Instead, what persisted was the other, more problematic form of magic: ritual magic. Klaassen shows that texts of medieval ritual magic were cherished in the sixteenth century, and writers of new magical treatises, such as Agrippa von Nettesheim and John Dee, were far more deeply indebted to medieval tradition—and specifically to the medieval tradition of ritual magic—than previous scholars have thought them to be.
“Well argued and well researched, [The Transformations of Magic] represents a thorough and scholarly treatment of medieval magical texts, as well as an engrossing read.”
“Klaassen’s elegantly written monograph is an incisive analysis of an understudied body of evidence. His argument that two types of ‘illicit learned magic’ characterized the period between 1300 and 1600 brings coherence and clarity to an intellectual tradition that has too often been overlooked. By locating magical texts within broad theological, philosophical, and scholarly traditions and by emphasizing the continuities between medieval ritual magic and Renaissance texts, Klaassen challenges his readers to see medieval and Renaissance intellectual culture in new ways. His work thus not only makes a valuable contribution to the history of magic in the premodern era, but it also participates in conversations about the periodization of the Middle Ages and the Renaissance. His study stood out in a year in which there were several strong contenders for the Labarge prize.”
“[Klaassen’s book] is a fine contribution to the field and his careful codicological analyses are highly convincing in supporting his argument.”
“Historians of magic are good at stifling conversation. Where they are expected to trade in ‘eye of newt,’ they offer dusty books. Where one expects witches, one finds monks. Scary spells become scholastic disputes about words and images and the typologies of magic. This means that historians of magic are good at talking to each other, but all too often alienate fellow historians of science, medicine, and religion who are their natural interlocutors. Frank Klaassen’s The Transformations of Magic: Illicit Learned Magic in the Later Middle Ages and Renaissance avoids this and is the most important history of magic in the last decade. Klaassen makes a serious intellectual contribution, and engages the concerns of historians who study all things natural and supernatural. Fitting to the history it tells, the book ranges from the thirteenth century through the seventeenth, traversing the medieval and early modern divide. . . . Like the best historians of magic, [Klaassen] spent many hours locating, reading, and classifying the documents, genres, codices—and the practices of producing them—that are fundamental to the transformations of magic. Klaassen’s tremendous sensibility for and attentiveness to the texts as artifacts is what makes this book so engaging and enduringly important. We meet the men—they were almost all men—who wrote, copied, and collected magic sources. They include people infamous and anonymous. We see these greedy monks, frustrated medical students, and ambitious natural philosophers sitting and writing, sometimes in a quick scrawl, sometimes in fine script and lavish colors. This is not about the history of books and readers. It is about understanding the motley corpus of extant magic texts now scattered across Europe’s libraries, most of it in sixteenth-century script and little studied by historians.”
“Frank Klaassen has written a thorough and well-researched study of selected magical texts in the Middle Ages and Renaissance. It should be of interest to scholars and serious readers of magic and related fields.

“Concentrating primarily on texts in manuscripts, Klaassen has performed a valuable service in aggregating texts from archives throughout Europe and North America. Though he focuses on British manuscripts, Klaassen casts a wider net in the themes and arguments he explores. . . . Klassen’s decision to explore the collections of magic texts in manuscripts is especially fruitful. He looks not only at the contents of his texts, but at how they were transmitted, the other texts with which they were collected, who copied them and why, and how the choices they made affected the presentation of the text. This wide-spectrum approach yields diverse textual and cultural information and provides a complementary perspective to the usual authorial study of magical texts.”
“[The Transformations of Magic] draws the reader very effectively into the murky world of semi- and fully anonymous characters out of which the luminary figures emerged and which encouraged the luminary characters to arise. We are introduced to a range of manuscripts the simple listing and indexing of which deserves mention as a great service. . . . [This] is a very good book based on a use of sources that is both careful and creative. The author’s central conclusions are clearly expressed, meticulously researched, and convincingly argued. It is exemplary in its subtle attentiveness to the relationship of ideas to the modes and details of their transmission, and it is compelling in its challenge to reconsider how certain kinds of magic’s place in Western society developed from the High Middle Ages to the early modern period. The Transformations of Magic is a richer piece of scholarship than its modest length might suggest.”
“In The Transformations of Magic, Frank Klaassen approaches the complex and important project of defining the intellectual context of medieval and sixteenth-century magical manuscripts and books. The strength of the book lies in his close reading of medieval magical manuscripts, which effectively locates them in the theological and natural philosophical milieu of the period. The second area of strength in this monograph, well supported by the evidence Klaassen provides, is his claim that early Renaissance magical authors owed a great debt to their medieval predecessors. . . . [Klaassen] deserves credit for writing an excellent analysis of the medieval material and providing the groundwork for more nuanced and careful thinking about the relationship between medieval and Renaissance magical thought and the evolving character of magic during this period.”
The Transformations of Magic is an inspiring and innovative work of scholarship on illicit learned magic. It sheds new light on problems with the transmission and transformation of magical traditions in a systematic manner. But more than this, it opens up important new vistas of inquiry for scholars interested in the longue durée of ritual magical texts, and suggests that more work is required on the complex, culturally productive relationship between experience, discernment, ritual technique, and textuality in Western magic.”

Frank Klaassen is Associate Professor of History at the University of Saskatchewan.




Part I: The Apothecary's Dilemma

1 Magic and Natural Philosophy

2 Scholastic Image Magic Before 1500

3 Some Apparent Exceptions: Image Magic or Necromancy?

Part II: Brother John's Dilemma

4 The Ars notoria and the Sworn Book of Honorius

5 The Magic of Demons and Angels

Part III: Magic After 1580

6 Sixteenth-Century Collections of Magic Texts

7 Medieval Ritual Magic and Renaissance Magic





This book is about illicit learned magic in England and the ways in which it was transformed between 1300 and 1600. It concerns the changes, sometimes subtle and sometimes dramatic, that took place each time a medieval author, scribe, or collector set out to understand and practice learned magic, and then to copy the associated texts or write new ones. It also deals with the transformations that entire genres of this literature underwent in the later Middle Ages and the sixteenth century. It seeks to understand what motivated these changes and what this tells us about the intellectual culture of late medieval magic.

The history of learned magic in the Latin West may be understood in part as a series of attempts to reconcile theologically problematic practices and ideas with Christian orthodoxy. This was a matter that concerned not only the authors of magic books but also the scribes and collectors who transmitted or preserved such texts. The nature of each reconciliation could, in principle, be quite distinctive and depended on a wide variety of factors, including the nature of the text received, any known authoritative reactions to it or the kind of magic it promoted, the context in which it was transmitted, and the copyist’s interests. A desire to see magic in terms of natural philosophy would, for example, demand a fundamentally different approach from a desire to regard it as a kind of mystical technology or religious exercise. A text known to have been condemned by an authoritative voice might generate a different response from one that had not. In addition, the intellectual world of late medieval scribes was not only a matter of solving abstract problems; it was circumscribed and informed by a number of broader conditions, such as the kinds of texts available and the professional context of the individual author, scribe, or collector. A monk’s interests, abilities, and resources were different from those of a medical doctor, student, or priest. A copyist’s profession affected not only what texts were available but also how they were interpreted, copied, and altered.

The processes involved in copying were thus very complex, and even where the original text was not altered in any way, the act of copying was not passive. On the contrary, it involved a wide range of choices, conscious or otherwise, that might fundamentally alter the sense of the received text. Which text would one choose, and which version? How would one find the text one wanted if one did not already have it? How should its legitimacy and value be judged? Should one alter the contents, omit parts, or extract a portion from its original context? If it was corrupt or fragmentary, how would one correct or supplement it so that it made sense? Might it be incorporated into a new text? How would it be presented on the page? Did it deserve its own folios or was it fit only for the margins, some loose parchment, or a pastedown? Would it be copied in a notebook, a schoolbook, or an illuminated manuscript? How should it look on the page? Once written, would it be annotated, glossed, indexed, or cross-referenced? Would it be strictly for personal use or available in a library? Finally, assuming that the scribe had the luxury of such a choice, in what kind of book would it be placed, that is to say, with what other kinds of texts should it be gathered for easy reference? Evidence of at least some of these decisions remains in each manuscript. To appreciate the broader changes in magic across the two and a half centuries covered by this book, and the interests and assumptions that lay behind them, we must begin by examining such data.

The transformations were far from random, and clear patterns emerge. The literature of illicit magic, and the way in which it was understood and treated, falls into two major streams. To illustrate the intellectual culture that in part determined the course of these streams, the first two sections of this book are introduced by the stories of two men, an unnamed apothecary and John of Morigny. In each case, the protagonist faces an essentially unsolvable problem. The apothecary must decide whether to believe that an astrological image that made him rich derived its power from occult natural properties or from deceptive demons. Brother John, by contrast, struggles to reconcile the fact that ritual magic was transmitted in books—books that one should assume were corrupt—but could only be learned, practiced, and understood through experiences that were not really communicable through the written word. How, then, could one learn to perform this magic, decide whether what one discovered was true or legitimate, and pass it on to others, when any written text might ultimately be corrupted? These problems form the creative core of the traditions of late medieval Scholastic astrological image magic collections and the literature of ritual magic.

The apothecary’s dilemma derives from the rationalist context of twelfth- and thirteenth-century Scholasticism and its Arabic forebears. A few key writers in this intellectual tradition offered the hope that the magical effects of astrological images might derive from natural processes rather than demonic deception. An intellectual debate concerning images, inspired by the writings of the ninth-century Arab philosopher al-Kindī, took hold in the twelfth-century Latin West and engaged the energies of many of the major Scholastic philosophers. It sought to evaluate this kind of magic with reference to authoritative discussions of the natural world and through a process of logical analysis. Although astrological image magic texts contained significant elements that could not be accommodated to naturalistic explanation, the associated debates about the natural world remained the intellectual rudder for how they were treated, a fact that transformed the library of image magic. While scribes tended to alter the contents of these works very little, the decisions they made about which ones to copy were powerfully influenced by authoritative discussions, particularly the Speculum astronomiae. Consequently, of the scores of texts once available, a relatively small group came to dominate the library. The transformation was also one of perspective: scribes understood these texts to be reconcilable with Scholastic ideas or, at a minimum, to belong to the larger discourse of natural philosophy. Even where we find no evidence of theoretical concerns, scribes still followed Scholastic thought and associated the texts with the genre of naturalia. In this way, a significant library of texts, many of which were not intended as—and did not claim to be—natural magic, were collected with other works concerning the natural world.

Part I of the book treats this topic. Chapter 1 describes how writers from Augustine, through al-Kindī, to Aquinas understood astrological images. It argues that, despite clear authoritative statements to the contrary, medieval intellectuals persisted in regarding these images as part of the literature of naturalia. Chapter 2 examines the manuscripts of astrological image magic and argues that in the later Middle Ages, particularly under the influence of the Speculum astronomiae, a pattern of collection developed that was so regular that it should be understood as a genre: the Scholastic image magic collection. Chapter 3 examines the few exceptions to the rule and argues that these manuscripts tend to confirm the rules in other ways. The habits of mind and patterns of collection in this literature stand in stark contrast to the literature of ritual magic, to which the next chapters turn.

Brother John’s dilemma arose from ritual magic, a different set of texts that flowed in an almost entirely discrete stream of transmission: demon conjuring, angel magic, and the theurgic arts, such as the Ars notoria, that emphasized the mechanisms of religious rites, dreams, and visions. For enthusiasts of this sort of magic, discovering truth was less about logical elaboration than about experience and revelation. The textual tradition they produced lacked the stabilizing effect that Scholastic debates had provided for astrological image magic. In fact, the mythologies written into the texts themselves encouraged the view that truth might very well not be found in any magic text, since ritual magic was less a repository of truth than a vehicle for its discovery. Authors, scribes, and collectors of these sorts of texts also acted with similar assumptions. A text had to accord with their ideas about what magical and/or religious rites should look like, and if its rituals produced any subjectively convincing experiences, these too could affect how the text was understood or treated. It is clear that scribes evaluated magic texts and regularly altered them on the basis of changing religious sensibilities, practical experience, or even what they took to be instruction by numinous powers brought about by their practices. Arguably, scribes were driven to this approach to truth as the only way to counterbalance the lack of clarity generated by the unstable transmission of ritual magic manuscripts: in order to make systematic sense of unsystematic traditions, suprahuman assistance was needed. The need to defend a tradition that was otherwise impossible to justify also pressed practitioners to claim divine guidance and sanction for their texts and practices through visionary experiences. This knot of problems helps us understand not only the far more unstable nature of ritual magic but also the resiliency and longevity of a form of magic that survives in a relatively robust form to the present day.

Accordingly, Part II of the book concerns the literature of ritual magic. It examines and compares the mythologies or literary representations of ritual magic practitioners within magic texts, the magical processes those texts ordained, and the way practicing magicians actually operated, including how they interacted with and transformed their texts. It argues that, unlike astrological image magic collections, ritual magic collections evince no interest in the literature of naturalia and lack stable textual traditions. Instead, their authors, scribes, and collectors had a strong interest in ritual processes, in highly personal or individualistic forms of magic, and in direct experiences of the numinous. This part of the book also argues that in this tradition, practitioners were encouraged by a variety of factors to transform received texts: ambivalence toward received texts, a mythology that encouraged practitioners to think of themselves as divinely guided editors or authors, and operations that emphasized the fundamental importance of individual experience, including subjectively convincing experiences of the numinous. Chapter 4 addresses the theurgic and largely angelic magic of the Ars notoria, John of Morigny’s Liber visionum, and the Liber iuratus Honorii. Chapter 5 examines the literature of necromancy, that is, operations involving both angels and demons.

Once we appreciate the distinguishing features of these two streams of thought, the distinctive blend of new and old in magic after 1480 comes clearly into view. This is the subject of Part III. Chapter 6 argues that although the late fifteenth and early sixteenth centuries are often characterized as a period when the superstitious “old dirty” magic of the Middle Ages was shed in favor of a more elegant magic of Hermetic or kabbalist inspiration, often associated with natural and astrological image magic, the magic manuscripts of this period exhibit no such shift. The most commonly copied texts of illicit learned magic at that time were works of late medieval ritual magic. Astrological image magic, on the other hand, and most particularly the Scholastic image magic collection, enjoyed its highest level of copying during the fourteenth and fifteenth centuries. It then almost vanished as an independent genre, and its texts, when they were copied at all, were typically subsumed within the larger literature of ritual magic. This situation cannot be explained by the increased availability of magic texts in print.

Chapter 7 attempts to make sense of all this by comparing the manuscript evidence with the magic of Marsilio Ficino, Cornelius Agrippa, and John Dee. It argues that the major occultists of the sixteenth century, particularly Agrippa and Dee, stood firmly in the tradition of late medieval demonic and angelic magic. Even Ficino’s magic, often understood as a limited kind of natural magic, was in fact a distinctively Neoplatonic system with great similarities to medieval ritual magic, highly ritualized and with powerfully religious, interior, experiential, and personal dimensions. Also like their medieval forebears, all three writers took up and transformed the older traditions, and they understood themselves as part of a divinely inspired renovation of magic. In short, Brother John’s dilemma lies at the heart of Renaissance magic.

Scholarly Context

This study begins with manuscripts. Unlike most studies of learned magic, however, and particularly works on Renaissance magic, it focuses upon a wide spectrum of scribes, collectors, and authors of magic works. The weakness of this approach is that the most eloquent proponents or elucidators of magic in the period are not treated in detail. The subtleties of their positions and the intellectual power of their writing often fade in a sea of intellectual mediocrity. The strengths of this approach, however, are considerable. First, by examining copyists and collectors rather than just authors, we discover important traditions, such as the Ars notoria, that have become invisible in the intervening years. Second, because most people are not exceptional, any understanding of the cultural world of late medieval magic should at least take cognizance of more ordinary intellectuals. Third, the exceptional Renaissance occultists, among them Ficino, Agrippa, Trithemius, Bruno, and Dee, did not write their works in a vacuum: great writers often become so through their ability to engage the concerns of their age. Their popularity, intellectual lineage, and originality are therefore better understood in the context of broader intellectual trends. In order to understand the significance of their books, we must understand their readers, on the one hand, and the magic traditions with which they were familiar, on the other. This approach also provides a kind of aerial view of the literature that transcends the divisions into which scholarship conventionally has fallen.

Until relatively recently, the historiography of illicit learned magic has fallen roughly into two streams that correspond to the two streams of transmission just identified. In one, historians concentrated on the relationship between science and magic, and in the other on the relationship between religion and magic. Lynn Thorndike’s eight-volume History of Magic and Experimental Science epitomizes the first approach. Although this monumental work includes a great deal of information on magic of a more “religious” kind, Thorndike’s treatment of necromancy and the Ars notoria is very limited, no doubt owing to the limited connections between these texts and the discourse of natural philosophy. Frances Yates significantly extended this approach to the Renaissance, emphasizing the connections of science with Renaissance magic, which she understood as fundamentally concerned with natural magic.

In the other stream, which emphasizes the relationship between religion and magic, such scholars as Keith Thomas, Norman Cohn, and Edward Peters have examined the relationship of magic to broader cultural issues, and have worked to locate magic in the complex nexus of moral, legal, and religious thought. Thomas’s classic Religion and the Decline of Magic assumed as its starting point that religion and magic were inextricably interwoven in the medieval period. Norman Cohn sought to understand the part that ritual magic played in late medieval conceptions of witchcraft and evil.

Scholars have also tended tacitly to assume a division between magic before and after the 1480s, when Marsilio Ficino and Pico della Mirandola produced their powerful new syntheses. Some, like Frances Yates, have explicitly contrasted medieval and Renaissance magic; but for the most part this has been an unspoken divide that few scholars have crossed. Like the division in scholarship between the scientific and religious aspects of medieval magic, this divide arises from and to a certain extent is justified by the sources. Renaissance writers incorporated the traditions of Neoplatonism and kabbalism in novel and very sophisticated ways. They also self-consciously rejected earlier traditions, particularly necromantic magic, and constructed their systems not only in opposition to prior magic texts but also in the self-conscious assumption that their age was engaged in a broad-based intellectual renovation that drew on the knowledge of antiquity. At the same time, this rejection belied the debts owed to their medieval forebears, and recent scholarship on the traditions of learned magic in the late Middle Ages and Renaissance demands that this division be reconsidered, or at least that the transition between medieval and Renaissance magic be better and more clearly articulated.

In recent decades scholars have begun to pick up the diverse threads of Lynn Thorndike’s remarkable survey of Western magic manuscripts in an attempt to open up this considerable and important literature. David Pingree and Charles Burnett in particular have broken new ground with their close studies of individual figures and texts associated with medieval traditions of Arabic magic. Although he had already published many articles on magic in the West (in addition to his survey Magic in the Middle Ages), Richard Kieckhefer’s edition and study of a fifteenth-century necromancer’s manual, Forbidden Rites, initiated a flood of editions and studies of specific texts, many by a new generation of scholars. The dean of magic studies in France, Jean-Patrice Boudet, produced a variety of important examinations of the Ars notoria and other texts and has led the way in editing the corpus of Solomonic literature in the Latin West. An edition of the Liber iuratus Honorii by Gösta Hedegård, followed by studies by Robert Mathiesen, Kieckhefer, Katelyn Mesler, Boudet, and Jan Veenstra, has expanded our awareness of this important text. Don Skemer has produced a study of textual amulets. Paola Zambelli has produced an edition and analysis of the Speculum astronomiae. Julien Véronèse’s important study and edition of the Ars notoria is perhaps the single most remarkable achievement, given the vast number of manuscripts involved. Sophie Page, Benedek Láng, and I have conducted studies of manuscript collection and transmission and have contributed to a growing body of scholarship on specific texts and manuscripts. Veenstra and Véronèse have provided important studies of other ritual magic texts as well. The profoundly compelling materials left behind by John of Morigny have been partially edited by Claire Fanger and Nicholas Watson, who are currently at work on additional parts of his corpus.

Work on Renaissance magic has also shifted to more focused examinations in recent decades; the literature is so vast that I can mention only a few studies that are directly relevant to this book. Brian Copenhaver, Michael J. B. Allen, Christopher Celenza, and Chaim Wirszubski have examined Ficino’s De vita coelitus comparanda and Pico della Mirandola’s Oration on the Dignity of Man, contributing substantially to our understanding of these difficult but central texts. Paola Zambelli, Michael Keefer, Vittoria Perrone Compagni, and Christopher Lehrich have expanded our understanding of Cornelius Agrippa’s De occulta philosophia. The magic of John Dee has been treated in detail by Nicholas Clulee, Deborah Harkness, Stephen Clucas, and an array of other authors.

In addition to this more focused scholarship, a number of important surveys now provide guidance to the broader traditions of medieval magic. Boudet’s study Entre science et nigromance is the most important general treatment of magic in the later Middle Ages and in many ways supersedes Kieckhefer’s Magic in the Middle Ages. Perhaps its greatest virtue is its tremendous breadth, including an examination of divination and astrology as well. Nicolas Weill-Parot’s Les “images astrologiques” au Moyen Âge et à la Renaissance surveys the literature of astrological image magic and the reactions of medieval scholars from al-Kindī to Ficino. Paolo Lucentini and Vittoria Perrone Compagni’s list of manuscripts of Hermetic texts (many of them concerning image magic) has superseded Thorndike’s work on this literature, as have comparable lists in the works of Boudet, Weill-Parot, and Véronèse. In addition to these, recent years have seen a wide array of thematic treatments of these and related subjects. William Eamon’s study of books of secrets and William Newman’s work on alchemy, while not focused precisely on magic, provide a useful backdrop against which other traditions of magic may be measured. At the same time, few studies of magic have attempted to survey illicit magic in general in both the medieval and Renaissance periods, a gap this study attempts to fill.

The relationship to this book of some of the scholarship I have mentioned merits explicit treatment here, particularly its relation to studies that attempt to outline broader historical developments in the history of illicit magic in the later Middle Ages and Renaissance. Keith Thomas’s classic Religion and the Decline of Magic argues that an inherently magical medieval church tended to preserve or even promote the practice of magic, its support fading with the Reformation. While my study does tend to confirm the argument that religion and the practice of ritual magic cannot be easily disentangled, it suggests, on the one hand, that this integration of magic and religion is one of the factors that allowed ritual magic to survive and to thrive after the Reformation, and, on the other, that magic, particularly medieval astrological image magic, cannot comfortably be collapsed under the broad rubric of religion, at least not in the Latin West. Instead, many of its proponents argued (or evidently assumed) that image magic was natural magic and was thereby as discontinuous with the practice of religion as any other natural tool would be. It was more precisely, as Weill-Parot has argued, the subject of an ongoing Scholastic debate surrounding what he has called its “addressativity,” that is, the uncomfortable reality that this form of magic appears to, or actually does, address spiritual beings that medieval theology insisted had to be demons. This study also confirms Weill-Parot’s contention that the high point of this genre was reached in the fifteenth century. I also follow Boudet’s suggestion, in Entre science et nigromance, that the medieval period was characterized by a fundamental ambivalence toward magic, but Boudet casts his net further than I cast mine, including the broader literature of astrology and divination. He also delves much more deeply into the connections between the history of magic and medieval institutions and the growth in the sophistication and tenor of condemnations of magic in the later Middle Ages. It is curious that this period of increasing condemnation was accompanied by a growing interest in magic, and Véronèse has suggested that it was also characterized by the development of the “author-magician.” I have developed, and articulate more fully here, a similar and parallel argument that the highly individual-centered magician of the later Middle Ages and Renaissance flows naturally from the practices and mythologies of ritual magic, which promoted the importance of the individual practitioner and the idea of the magician as a divinely guided editor. With respect to the transition between the Middle Ages and Renaissance, evidence presented here suggests that the stark division of medieval and Renaissance magic promoted by many scholars, particularly by Frances Yates, cannot be sustained. Despite my reservations about Brian Vickers’s evaluation of Renaissance magic, he is quite right to note that most magic in the sixteenth century looked very little like what Yates imagined and rather more like what she called the “old dirty magic” of the Middle Ages. In addition to demonstrating the continuity of Renaissance magic with medieval traditions, then, I hope that this study will help redeem the old magic and prove it worthy of study.

Two other scholars not directly concerned with magic also deserve mention here. William Eamon’s Science and the Secrets of Nature emphasizes the division between Scholastic natural philosophy and the literature of naturalia, particularly books of secrets, on the grounds that the former offered explanations for observed realities, whereas the latter, at best, offered demonstrations of those ideas. While recognizing the quia–propter quid division, my study emphasizes the continuity between debates in Scholastic natural philosophy (propter quid) and habits of mind in the wider literature of naturalia, including experiments, secrets, divination, and astrological image magic (largely quia), and argues in particular that Scholastic natural philosophy fundamentally influenced the fortunes of astrological image magic texts. Eamon’s work also emphasizes the practical nature of much of the secrets literature. In a similar vein, and like William Newman’s Promethean Ambitions, which focuses heavily upon the practice of alchemy, my study takes seriously the idea that magic, even when it was a largely theoretical activity, was still a practice involving habits of authorship, translation, selection, copying, analysis, and practical application. These habits provide crucial evidence for understanding the intellectual culture of illicit learned magic in the premodern world.

Assumptions and Terminology

I use the terms “magic” and, less often, “religion” and “science” as useful general categories only. The modifiers “religious” and “scientific” are easily understood ways of referring to a very real division in premodern treatments of magic. Naturally, those who copied astrological image magic texts into volumes containing works of Scholastic natural philosophy were no less religious than the scribes of ritual magic, nor were the latter less “scientific” than the former. Yet the manuscripts do reveal different ways of approaching and thinking about the texts. If the Scholastic approach to magic texts was framed by religious questions (and it certainly could be), it was, at the same time, fundamentally concerned with physical processes, natural phenomena, and related theoretical questions. Similarly, if ritual magic texts reveal a more explicit desire to connect with the numinous, to perform powerful liturgical rites, and to engage in magic in an effective way, almost all of their scribes would have had Scholastic training. So there is no reason to assume that these approaches were in any way mutually exclusive. That some medieval scribes participated in both traditions, and that Renaissance writers and scribes merged these two streams, argues very strongly that they are better understood as distinctive modalities of relation or discourse. Similarly, the term “magic” is tremendously vague. I engage in a modern anachronism when I use this term, for many of my scribes did not use it, nor did they necessarily regard their practices as “magic.” Nevertheless, use of the term may be justified by the fact that most authorities would have regarded all of the practices considered in this book as illicit, and therefore as magic.

Boudet has pointed out that writers commonly used the term “nigromancy” to refer to magic of which they approved and “necromancy” for magic of which they did not. A practitioner of demon conjuring was thus likely to refer to himself as a nigromancer, and it follows that to use the term “necromancer” to describe him might be anachronistic. However, the term “nigromancy” lacks precision, as it was used to refer both to astrological image magic and also to ritual magic, traditions that this book seeks to distinguish. Further, when a medieval catalogue identifies a book as necromantic or nigromantic, this does not necessarily mean that it was a work of demon conjuring. For example, a German medieval catalogue refers to works of astrological image magic simply as necromantic. This was simply a negative valuation of astrological image magic, but in the absence of the accompanying description it is impossible to know whether the texts were astrological image magic or explicit demon conjuring. The terms are thus inherently ambiguous and depend on the (perhaps unknown) point of view of the author. For this reason, I use the term “necromancy” in the conventional sense, to refer only to those activities that the authors, scribes, and collectors explicitly regarded as involving the conjuring and deploying of demons.

An additional problem with the term “magic” is that it can be taken to imply a practice that is inherently inefficacious. I do not regard medieval assumptions about the world as in any way absolutely true. But the magical processes they described were assumed to be real, and I do accept that, in many cases, they did work. Certainly, practitioners could assign results to their magical operations in retrospect, but subjective experience of magic is far more complex than this. Ritual magic employed human mediums, reflecting surfaces (fingernails, mirrors, water, or “show stones”), transparent substances (crystals or vials), and randomly moving things (fire or smoke), which could have evocative power even in the absence of meditative or trance states. Dreams, a fairly regular occurrence in everyday human experience, were also common vehicles for ritually induced visionary experiences. Recent studies, such as those by Tanya Luhrmann, have demonstrated that the techniques of modern magic, which differ in only limited ways from their medieval forebears, can result in subjectively convincing and even life-altering experiences. Certainly, the medieval worldview provided abundant encouragement for the belief that these kinds of experiences could occur: conventional Christianity commonly employed visions and reports of visions as a way to access divine mysteries, and as Richard Kieckhefer has observed, very few people in the medieval period did not believe in demons and angels. Given a state of suggestibility or altered awareness brought about by an ongoing discipline of meditation or visualization and more immediate evocative stimuli, it should be unsurprising that experiences ranging from feelings or impressions to visual or auditory hallucinations might follow. Of course, it is conceivable that some authors and scribes failed in their magical efforts, but we have every reason to assume that they copied magic texts under the assumption that the practices described therein could work. Similar conditions surrounded image magic: although there was some debate about how it worked—whether it operated because of astrological influence or demonic intervention—the assumption remained that it did work. Throughout this study I assume that the practices described probably did achieve some subjectively convincing results, and if not, that the practitioners would have better cause to doubt their texts or techniques than to question the principle that magic could work.

Sensitive readers will also be aware that it is problematic to use the term “scribe” to indicate the person whose intents and interests are reflected in the text. It is, of course, unclear whether the texts were copied by professional scribes or were the work of the person directly interested in magic. It may be that both participated in the selection and transmission of the text. In fact, a single manuscript may reveal a startling complexity of “archeological” layers, each represented by a different person. It may have been assembled from several previous books, each assembled by a different person. The complete surviving codex, or any of the parts of which it is made up, may have been owned, that is, collected, by numerous people. It also may contain any number of the various levels of authorship or authorial intervention. This is one of the great riches of the medieval codex, but any attempt to reflect this complexity can make for some very clumsy writing. In order to simplify things, and to avoid the endless repetition of awkward phrases like, “the scribe, the person who directed the copying or paid for it, the collector or the group who collaborated on this manuscript, the authors, extractors, or those who in some way made authorial interventions,” I often simply refer to this person or group in the singular as “the author, scribe, or collector,” or sometimes “the scribes.” I trust that my readers will indulge me in this matter.