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Galileo’s Idol

Gianfrancesco Sagredo and the Politics of Knowledge

Publication supported by the Susan Elizabeth Abrams Fund in History of Science

Galileo’s Idol offers a vivid depiction of Galileo’s friend, student, and patron, Gianfrancesco Sagredo (1571–1620). Sagredo’s life, which has never before been studied in depth, brings to light the inextricable relationship between the production, distribution, and reception of political information and scientific knowledge.
Nick Wilding uses as wide a variety of sources as possible—paintings, ornamental woodcuts, epistolary hoaxes, intercepted letters, murder case files, and others—to challenge the picture of early modern science as pious, serious, and ecumenical. Through his analysis of the figure of Sagredo, Wilding offers a fresh perspective on Galileo as well as new questions and techniques for the study of science. The result is a book that turns our attention from actors as individuals to shifting collective subjects, often operating under false identities; from a world made of sturdy print to one of frail instruments and mistranscribed manuscripts; from a complacent Europe to an emerging system of complex geopolitics and globalizing information systems; and from an epistemology based on the stolid problem of eternal truths to one generated through and in the service of playful, politically engaged, and cunning schemes.

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232 pages | 4 color plates, 6 halftones | 6 x 9 | © 2014

Biography and Letters

History: European History

History of Science

Library Science and Publishing: Publishing

Physical Sciences: History and Philosophy of Physical Sciences


"Brilliant, thoughtful, and an absolute pleasure to read."

New Books in Science, Technology, and Society

"This slim volume is one of the most intriguing books to appear on Galileo in recent years. It is refreshing to read an account that moves forward, letting the material, rather than ponderous historiography, drive the tale."

Journal for the History of Astronomy

"Wilding's Galileo's Idol is a short and ambitious book, both in the tasks it sets for itself and in the wide variety of debates in which it intervenes. His story is exciting, illuminating and engaging, and he seeks not to close debates but rather to open them: to suggest how we might tell old stories in new ways."


"The complex image of Galileo often looms so large that it obscures the fundamental roles of key agents in his success in the various political, philosophical, and publishing networks in which he operated. Galileo’s Idol offers a rich portrait of one such agent: the friend, supporter, politician, and Venetian intellectual Gianfrancesco Sagredo (1571–1620). Throughout Galileo’s Idol, Wilding tells a vivid tale that draws the reader into this historical moment. Scholars new to early modern studies will benefit from the engaging readability of his prose; those with a background in Galileo’s early years will be drawn to the translations of recently discovered primary materials and the new resources identified by the notes. As Galileo’s idol, Sagredo certainly deserves this reconstruction of his agency in the period. Wilding’s conscientious study of so many objects reveals that the stained and splintery printer’s house and the grimy ocean voyages of ambassadors’ letters can provide new and complementary insight into our understanding of early modern science."

The American Historical Review

"Whenever Wilding discusses seemingly complex social and political issues—such as the 1606 Venetian Interdict or the Venetian, Persian, Ottoman, Roman, and Habsburg spy games—he carefully avoids getting bogged down in political detail and skillfully brings the reader’s attention to the relevance of such matters to Galileo and his collaborators....It is a testament to Wilding’s attention to detail and patient archival work, as well as his engaging style of writing, that these revelations relating to Galileo’s baroque context are so clearly exposed in Galileo’s Idol. Additionally, the book contains an important historiographical reminder: discursive and publication strategies played an important role in the competition over natural philosophical thought."


"The major strength of this book lies in how the material world of early modern texts and images is interpreted in terms of social and intellectual relations. Within this framework, the figure of Gianfrancesco Sagredo appears under a different light from the one of the learned amateur to which Galileo’s readers have been accustomed. In Wilding’s study, Sagredo becomes an active agent in the production and use of a variety of texts, manuscript and printed, both private and public (although the distinction is manifestly fluid in this story), a patron and political ally of Galileo, and in some ways exemplary of the way in which early modern scientific information and knowledge was constructed and circulated. Galileo’s Idol makes for an enjoyable and stimulating read, not least because of the author’s ability to open up and exploit different channels of communication between disciplines and theoretical approaches."


“Best known as the sidekick in Galileo’s Dialogue, Sagredo comes to life here as a real person. Wilding’s careful sleuthing reveals the crucial roles that Sagredo and other intermediaries played in facilitating the flow of books and letters, of information and disinformation, from Aleppo to Venice and beyond around the turn of the seventeenth century. This book sheds brilliant new light on Galileo’s entangled efforts to gain money, reputation, and scientific knowledge.”

Ann Blair, Harvard University

Galileo’s Idol is an engaging, original, and important work, and it makes several crucial contributions to early modern history of science. First and foremost, Wilding revises in significant ways our understanding of the two main protagonists, Galileo Galilei and Gianfrancesco Sagredo, bringing into focus a great deal of new information about their relationship to each other, to the Venetian Republic, to other natural philosophers of their day, to the bookmen whose business it was to import and export such knowledge, and to that looming exilic community, the Society of Jesus. In addition, he uses new information, much of it painstakingly reconstructed from archival materials, to argue for something other than a prescient, far-sighted, single-minded Galileo—that is, for one whose multiple strategies and various allegiances were contingent moves, not always successful and occasionally in conflict with each other. Wilding’s study brings attention to issues such as the relationship of natural philosophy to statecraft; the establishment, shaping, and distortion of authorial identity; and the relevance of book and manuscript history to our understanding of how information traveled and was consumed by a vast range of readers.”

Eileen Reeves, Princeton University

“In Wilding’s hands, Sagredo becomes a window onto two overlapping worlds: the culture of European baroque science and that of the Venetian patriciate. In both cases we are treated to new, powerful, and surprising insights, not to mention unexpected evidence that most historians thought unavailable. Through Sagredo, we see Galileo at an angle that no previous study or biography has been able to capture, and we also watch the Venetian patriciate from the ground up, through the mundane daily practices that made that culture so unique. The locus of Galileo’s Idol is remarkably local—a few small islands in a lagoon—but the picture we see is quite different: a small insular community that is what it is because of its vast networks—not only military and commercial, but also networks of oral and printed communication. Through an emphasis on technologies of communications, Wilding demonstrates how much the Venetian patriciate and Galileo’s career were a result of media—both the production and circulation of books, manuscripts, notes, and gossip and their skilled and often subversive readings. Galileo’s Idol is detective work at its best, building new complex tableaux from newly found or noticed traces and indexes scattered far and wide. A must read for anybody interested in Galileo, early modern science, Venetian history, and Mediterranean studies.”

Mario Biagioli, University of California, Davis

Table of Contents


1 The Generation and Dissolution of Images
2 Becoming a “Great Magneticall Man”
3 Drawing Weapons
4 Interceptions
5 Interconnections
6 Transalpine Messengers
7 Masks

Conclusion: Science, Intercepted

List of Abbreviations


MLA: Scaglione Prize for Italian Studies

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