The Counter-reformation sterilized this swarm of popular forces: The Society of Jesus is the last great religious order -reactionary in its origin and authoritarian, with a repressive and 'diplomatic' character -that marked with its birth the hardening of the Catholic organism. [...] Catholicism has become 'Jesuitism'.Antonio Gramsci, Q. 11, 1384 1 'Jesuit Science' is a bizarre plant flourishing in the field of historical studies in the early modern period. While other historiographical species such as 'German Physics' or 'Proletarian Science' have been equated and banned for their impure ideological pedigrees, 2 religiously tinged con-species, such as 'Islamic Science', have been replaced by more nuanced ones such as science in Islamicate societies. 3 As for the sub-species of Christian Science, 'Jesuit Science', it is propagating at an extraordinary pace. First articles, and then edited volumes and monographs on the subject have appeared and multiplied, so that it has become fairly common to encounter this keyword in the titles of scholarly works. 4 The claim and concern of this article is that today 'Jesuit Science' only prima facie refers to a historical problem, that is, the investigation and comprehension of scientific debates involving scholars belonging to the Jesuit Order during early Modernity. 5 By taking a