Summary. Is Philosophy a Rigorous Science? Bolzano, Brentano, Husserl

Assuring to philosophy the status of rigorous science is an ambition that joins, albeit in their diversity, the philosophical positions of Bolzano, Brentano and Husserl. This paper aims to show what the main features of such a meta-philosophical orientation are and identifies its roots in the paradigmatic role - in Bolzano and Husserl - of logic and mathematics as models of conceptual rig-or, while in Brentano's case it is rather the empirical basis of the psychological investigation of mental acts that provides to philosophical reflection the rigor of a science. In this context a common frame of reference is Leibniz's mathesis universalis, while Kant is instead a mostly negative term of comparison, although Husserl's phenomenology entails in its late formulation a kind of reconciliation with Kant's transcendentalism. The outcome of this philosophical story, however, seems to down grade the idea that philosophy, to be such, must only be a rigorous science. As a humanistic discipline, philosophy can also be configured differently from an exclusively epistemological connotation; and even Bolzano, Brentano and Husserl did not escape this fate either.