This introductory article provides an overview of the historiography of scientific secrecy from J.D. Bernal and Robert Merton to this day. It reviews how historians and sociologists of science have explored the role of secrets in commercial and government-sponsored scientific research through the ages. Whether focusing on the medieval, early modern or modern periods, much of this historiography has conceptualized scientific secrets as valuable intellectual property that helps entrepreneurs and autocratic governments gain economic or military advantage over competitors. Following Georg Simmel and Max Weber, this article offers an alternative interpretation of secrecy as a tool to organize and to hierarchically order society. In this view, the knowledge content of secrecy is less important than its social-psychological effects. The authors argue that, in many instances, entrepreneurial researchers and governments use scientific secrets as an effective tool to manipulate the beliefs of their competitors and the larger public, and not necessarily to protect the knowledge that they hold.

Traditional historiography of science has constructed secrecy in opposition to openness. In the first part of the paper, I will challenge this opposition. Openness and secrecy are often interlocked, impossible to take apart, and they might even reinforce each other. They should be understood as positive (instead of privative) categories that do not necessarily stand in opposition to each other. In the second part of this paper, I call for a historicization of the concepts of ‘openness’ and ‘secrecy’. Focusing on the early modern period, I briefly introduce three kinds of secrecy that are difficult to analyse with a simple oppositional understanding of openness and secrecy. In particular, I focus on secrecy in relation to esoteric traditions, theatricality and allegory.

A new political practice, the ‘reason of state’, informed the ends and practices of natural study in the late sixteenth century. Informed by the study of the Roman historian Tacitus, political writers gathered ‘secrets of empire’ from both history and travel. Following the economic reorientation of ‘reason of state’ by Giovanni Botero (1544–1617), such secrets came to include bodies of useful particulars concerning nature and art collected by an expanding personnel of intelligencers. A comparison between various writers describing wide-scale collections, such as Botero, Francis Bacon (1561–1626), Jakob Bornitz (1560–1625) and Matthias Bernegger (1582–1640), reveals that seventeenth-century natural intelligencers across Europe not only were analogous to political intelligencers, but also were sometimes one and the same. Those seeking political prudence cast themselves as miners, prying precious particulars from the recesses of history, experience and disparate disciplines, including mathematics, alchemy and natural philosophy. The seventeenth-century practice of combining searches for secrets of empire, nature and art contests a frequent historiographical divide between empirical science and Tacitism or reason of state. It also points to the ways political cunning shaped the management of information for both politics and the study of nature and art.

I make three related claims. First, certain seemingly secretive behaviours displayed by scientists and inventors are expression neither of socio-professional values nor of strategies for the maximization of the economic value of their knowledge. They are, instead, protective responses to unavoidable risks inherent in the process of publication and priority claiming. Scientists and inventors fear being scooped by direct competitors, but have also worried about people who publish their claims or determine their priority: journal editors or referees who may appropriate the claims in the manuscript they review or patent clerks who may claim or leak the inventions contained in the applications that cross their desks. Second, these protective responses point to the existence of an unavoidable moment of instability in any procedure aimed at establishing priority. Making things public is an inherently risky business and it is impossible, I argue, to ensure that priority may not be lost in the very process that is supposed to establish it. Third, I offer a brief archaeology of regimes and techniques of priority registration, showing the distinctly different definitions of priority developed by each system.

Freud's analogies were legion: hydraulic pipes, military recruitment, magic writing pads. These and some three hundred others took features of the mind and bound them to far-off scenes – the id only very partially resembles an uncontrollable horse, as Freud took pains to note. But there was one relation between psychic and public act that Freud did not delimit in this way: censorship, the process that checked memories and dreams on their way to the conscious. (Freud dubbed the relation between internal and external censorship a ‘parallel’ rather than a limited analogy.) At first, Freud likened this suppression to the blacking out of texts at the Russian frontier. During the First World War, he suffered, and spoke of suffering under, Viennese postal and newspaper censorship – Freud was forced to leave his envelopes unsealed, and to recode or delete content. Over and over, he registered the power of both internal and public censorship in shared form: distortion, anticipatory deletion, softenings, even revision to hide suppression. Political censorship left its mark as the conflict reshaped his view of the psyche into a society on a war footing, with homunculus-like border guards sifting messages as they made their way – or did not – across a topography of mind.

In recent years, the selective flow of knowledge has emerged as an important topic in historical and social studies of science. Related questions about the production of ignorance have also captured attention under the rubric of agnotology. This paper focuses on information control in interaction, examining how actors seek to control the flow of scientific knowledge as they interact with others, either in face-to-face encounters or in modes of communication involving circulating documents, data, materials and other entities containing knowledge. The analysis uses an ethnographic approach to study how actors work to control which knowledge becomes available to whom, when, under what terms and conditions, and with what residual encumbrances. Secrecy, for example, is not framed as an isolated, sui generis phenomenon, nor as one side of a secrecy/openness dichotomy, nor even as a pole on a secrecy/openness continuum. Instead, the analysis explores how actors manage a dialectic of revelation and concealment through which knowledge is selectively made available and unavailable to others, often in the same act. The emphasis on selective revelation highlights partial transfers of knowledge, targeted distribution, matters of timing, and the rights and encumbrances that attach to knowledge at different points in its transit. Examples are drawn from genome research, a field marked by ongoing disputes about modes of information control.