Thanks to a grant of the Nordrhein-Westfälische Akademie der Wissenschaften und der Künste, Bielefeld University has started a fifteen-year project (2015-2030) that includes the production of a critical edition of Niklas Luhmann's extant works and manuscripts, as well as the digitalization of his famous card index. This valuable enterprise has rekindled interest in what many scholars hold to be a
... [Show full abstract] 'holy grail': a marvelous instrument that aided great creativity and scientific production by the German sociologist. Indeed, people feel that looking inside the filing cabinet is like looking inside the mind of a genius at work. This article suggests a different viewpoint rooted in the Enlightenment project of the sociologist of Bielefeld. The main hypothesis is that, if one considers the evolution of knowledge management in early modern Europe, there is nothing particularly surprising in the use of a card index as a surprise generator. Rather, the question should be how is it possible to explain the evolutionary improbability of the social use of 'machines' as secondary memories for knowledge management and reproduction? This article provides some suggestions for research and explores where Luhmann's card index comes from. © 2017 Erudition and the Republic of Letters. All rights reserved.