In a Neapolitan gazette of the late seventeenth century, the Giornali di Napoli dal MDCLXXIX al MDCIC, Domenico Confuorto remembered Giacinto De Cristofaro's years in the inquisitorial prisons of San Domenico for having ‘followed the cult of the Epicureans or atheists’. This quote introduces the main historical problem discussed in the following pages: how did the Holy Office succeed in manipulating intellectual categories, such as Epicureanism and atheism, to reach political goals in early modern Naples? Along with a clearly philosophical definition—that referring to the ‘Epicureans’—we find the term ‘atheism’, the meaning of which, in the language of the institutions devoted to supervision of the faith, was much less clear. By calling De Cristofaro, his friends, and colleagues ‘atheists’, Confuorto did not imply any connection with the intellectual current that had revitalized the Renaissance tradition of atheism. In his view, atheism was first of all a useful category: it could both cover a wide range of accusations and label any form of political and intellectual innovation during the Kingdom's complex political transition.

Truth is always conceptualized within a precise historical frame in which politics, religion, and culture combine. This seems particularly apparent in the Neapolitan case at the core of this chapter. In the following pages, I analyse the conflict between the secular and ecclesiastical elites of Naples (namely the archbishop, the Holy Office, and the viceregal court) and the local followers of the Cartesian movement, the so-called novatores, who took a strong philosophical stance against the Aristotelian orthodoxy.