The papers in this issue of Studium were presented at workshops organized by the Scientific Research Network ‘Circulating Knowledge in Early Modern Science (c.1450–c.1800)’, sponsored by the Flemish Research Council (FWO-Vlaanderen). Other workshops addressed the circulation of material objects, the problems associated with the translation of knowl­edge, the identification of centres of accumulation and the wider connections between geograph­ical spaces. Many of the papers presented in these workshops are – or will be – published.1 The final conference (held in March 2011) applied the concept of circulation to a review on the history of early modern science in the Spanish Netherlands.

It is widely accepted among historians of science that the production of knowledge is first and foremost a localized process. Whether knowledge emerges from direct observation, from experimental practices or in the interaction of different actors, the localized setting plays a crucial role in understanding its conceptual and epistemic features. This does not mean, however, that knowledge is confined to one privileged location. Knowledge can be transmitted from one location to another, thereby transcending geographical, social and epistemological boundaries. Yet, in doing so, knowledge becomes transformed, translated, adapted and rephrased. Knowledge is both enriched with new meanings, and thinned out by the separation from its original environment. The circulation of knowledge is therefore a productive process in its own right, which deserves to be studied as such.2

The four papers in this special issue explore the role of institutions and networks in the circulation of knowledge. Ranging from correspondence networks to scientific journals and universities, these papers all center around the question how knowledge is put together from different, geographically remote locations, and how this ‘foreign’ knowledge is presented to a ‘local’ audience.

Andrea Ubizsy Savoia analyses the attempts of Federico Cesi to build a network of institutions around his Lincean Academy, and to stimulate his academicians to collaborate in collective research. Samuel Gessner reconstructs the transmission process at work in the production of the treatise on mathematical instruments by the Portuguese Jesuit Ignace Stafford. Mihnea Dobre offers a close reading of the representation of Cartesianism in the Journal des Sçavans, as a way to establish the published discourse on Cartesian philosophy among the readers of the journal. Geert Vanpaemel points to an alternative channel of communication at work in the university of Louvain, demonstrating the complexity of the circulation process.

These papers demonstrate how the actors involved in the transmission of knowledge contribute to the available stock of information, from which local users can make their pick. When this transmission process can be traced in the case of institutional carriers (such as academies and journals), it is more obscure and contingent, then when individual actors are the prime movers of information. The changes in knowledge can also be quite diverse: either by addition or omission of information; by a change of style or perspective; by a translation between languages, or between textual and visual discourse. Actors were often conscious of the changes they brought about to the original knowledge. Their motives ranged from adaptation to local taste and interest; they careful negotiated the boundaries between the care for novelty and the fear of censorship. Reading the papers in this volume with these questions in mind, one is struck by the complexity of the processes involved and by the fecundity of historical approaches, to unravel the many layers of interpretation involved.