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Forbidden Knowledge

Medicine, Science, and Censorship in Early Modern Italy

Forbidden Knowledge

Medicine, Science, and Censorship in Early Modern Italy

An exploration of the censorship of medical books from their proliferation in print through the prohibitions placed on them during the Counter-Reformation.

Forbidden Knowledge explores the censorship of medical books from their proliferation in print through the prohibitions placed on them during the Counter-Reformation. How and why did books banned in Italy in the sixteenth century end up back on library shelves in the seventeenth? Historian Hannah Marcus uncovers how early modern physicians evaluated the utility of banned books and facilitated their continued circulation in conversation with Catholic authorities.
Through extensive archival research, Marcus highlights how talk of scientific utility, once thought to have begun during the Scientific Revolution, in fact, began earlier, emerging from ecclesiastical censorship and the desire to continue to use banned medical books. What’s more, this censorship in medicine, which preceded the Copernican debate in astronomy by sixty years, has had a lasting impact on how we talk about new and controversial developments in scientific knowledge. Beautiful illustrations accompany this masterful, timely book about the interplay between efforts at intellectual control and the utility of knowledge.

360 pages | 40 halftones, 2 tables | 6 x 9 | © 2020

History: European History, General History

History of Science


“A remarkable book indeed, at once learned and engaging, well written and well conceived. It is also thoroughly researched. . . . Marcus provides us with a refreshing perspective on medicine, science, books, reading practices, professional self-definition, the discourse of utility, and the acquisition and dissemination of knowledge in early modern Italy. Her own book, which is well illustrated with thirty-six figures, is both illuminating and a pleasure to read.” 

Journal of Modern History

"Wonderful. . . . [The book] offers and provokes meditation on the timeless nature of censorship, its practices, its intentions and, perhaps especially, its (unintended) outcomes. . . . Forbidden Knowledge also makes an important intervention in the debate about Counter-Reformation Italy, still often represented as dominated by repressive Catholic institutions. Marcus' study of the censorship of medical texts reveals a much richer picture. . . . The book offers an invaluable meditation on the processes meant to distinguish good knowledge from bad, and the fluidity of those categories."

Times Higher Education

"Many years have passed since microhistory was the latest fashion in historiography, but [this] complex, extremely erudite, nuanced, and very carefully researched book by Hannah Marcus shows how its legacy is still with us, reinterpreted in creative and innovative ways. . . . This book, written with clarity, passion and erudition at the same time as being extremely well-researched, is a model of history writing and has the potential of becoming a classic."


"Marcus expertly explores the mechanics and meaning of the censorship of medical writings in post-Tridentine Italy in this innovative and original study. . . . Forbidden Knowledge succeeds on multiple levels that allow for the revision of many assumptions about post-Tridentine intellectual activity. By providing details into the practices of expurgation and licensing, the book delineates the priorities of the Catholic Church, while demystifying censorship. . . . Additionally, she unveils the interests and priorities of the medical community in a manner that exceeds what is often found in traditional intellectual histories. . . . Most importantly, Marcus deftly explains the various contradictions that shaped the interactions between Catholic authorities and the medical and scientific communities of early modern Italy, showing how these dynamics defined the role of outside expertise in creating 'Catholic Knowledge' for centuries to come." 

Annals of Science

"Throughout, Marcus expresses her insights in a very readable prose enriched by an excellent eye for telling anecdotes. . . . Marcus has provided an impressively researched book that makes several important contributions to understanding the application of Reformation-era Catholic censorship to the intellectual world of Italian learned medicine. There is much to draw on, and build on, in this book."

Social History of Medicine

"[A] meticulously researched study. . . . This monograph presents a series of powerful and convincing arguments about the shaping of both Catholic culture and scientific knowledge in the early modern period, but it is equally rich in material for scholars from different disciplinary and methodological viewpoints. Marcus deftly deploys the techniques and concerns of scholars who study the history of book production—collecting, material culture, literacy, and reading. In short, her work presents a compelling argument married to an innovative series of methodologies."

Journal of Interdisciplinary History

"This book is a fascinating exploration of the efforts of Catholic authorities to
delineate the boundaries of scholarship and the concerted efforts of physicians to transcend these through smuggling books and learned navigation of the structures of censorship. Marcus demonstrates, with considerable skill and insight, the limits to Catholic censorship as well as surprising effects."

Project Muse

"This is an important study that all scholars and advanced students of early modern Europe will want to read, especially those interested in early modern medicine, religion, and the history of the book. . . . Highly recommended."


"Marcus shows how censors did their job in Counter-Reformation Italy, using medicine as a test case. Censors’ tools ranged from humanist techniques for reading, which enabled them to find and highlight problematic passages, to pens and scissors, with which they defaced the names of religious enemies and much more. But their means and powers were always limited. Drawing on unexplored documents, Marcus also recreates the system of permissions that enabled medical men to stay abreast of the new books printed in Protestant Europe. As lively as it is learned, this book reveals that Italian libraries witnessed as many scenes of struggle as of repression."

Anthony Grafton, Princeton University

Forbidden Knowledge is a fascinating story of what can go wrong in censorship regimes when the censored field is seen as essential to human health and welfare, and when the works of the authors most in need of censoring are widely recognized as indispensable to the field. In this impeccably researched book, Marcus brings her story alive by focusing on the people involved in censorship and expurgation: frustrated administrators, busy and uncooperative professors, expert readers eager to pad their libraries at the Church’s expense, and an expurgator so pious he insisted on censoring his own works. An important contribution to the histories of early modern medicine, censorship, and the book."

Katharine Park, author of Secrets of Women: Gender, Generation, and the Origins of Human Dissection

"Marcus’s story about censorship ranges much more widely than most Anglophone accounts of the topic. Her point is that the system as we see it developing in sixteenth-century Italy was not only a device for suppressing texts, but a collection of practices for editing them, approving them, and directing their circulation. The book is provocative, overdue, and exciting. It will become an obligatory point of reference in the field, and I can imagine it acting as the launching pad for a generation of future studies."

Adrian Johns, author of Piracy: The Intellectual Property Wars from Gutenberg to Gates

Table of Contents

Introduction: The Paradox of Censorship

1. The Medical Republic of Letters and the Roman Indexes of Prohibited Books

2. Locating Expertise, Soliciting Expurgations

3. The Censor at Work

4. Censoring Medicine in Rome’s Index Expurgatorius of 1607

5. Prohibited Medical Books and Licensed Readers

6. Creating Censored Objects

7. Prohibited Books in Universal Libraries




American Catholic Historical Association: Helen and Howard R. Marraro Prize in Italian History

Journal of the History of Ideas: Morris D. Forkosch Prize

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