Angela N. H. Creager is the Thomas M. Siebel Professor in the History of Science at Princeton University, where she directed the Shelby Cullom Davis Center for Historical Studies from 2016-20. Jean-Paul Gaudillière is Senior Researcher at the Institut National de la Santé et de la Recherche Médicale, and Professorat the Ecole des Hautes Etudes en Sciences Sociales, Paris.