Abstract
A well-established historiography has pointed out the distinction between first philosophy and theology, proposed by Benet Perera in his De communibus, as the “birth” of modern ontology. Ontology is often defined as an independent or neutral science by modern authors as well as contemporary scholars.This paper aims to show the way in which Perera comes to this distinction, after a long reflection on the status of mathematics and abstractions of theoretical sciences matured during his lectures at the Collegio Romano.Interestingly, it appears that after the subject of ontology is removed from its relationship with God and rational theology, ontology does not seem to acquire the status of neutral and universal science that Perera sought. Ontology becomes, in fact, a science dependent on the definitions provided by other disciplines and sciences, such as logic and mathematics.Following these recent findings, the paper also provides a renewed confrontation b..