Bolzano e gli stoici

Although Bolzano rarely mentions the Stoics, there is a substantial correspon-dence between the Bolzanian doctrine of “an sich” and the Stoic logic of proposi-tions. For both, in fact, the fundamental logic element is not the name or term, but the complete sentence in inner sense of which – such as Bolzano “objective con-tent” and the Stoics lekton, i.e. the “sayable” or “that which is meant” – lies the cri-terion of truth. It is a propositional semantic with semiological foundation, defin-able as a logic of the structure, so far from correspondentism as from purely syntacti-cal and coherentist models. However, while the Stoics based their logic on a given cosmological conception, the center of which is the archaic notion of “event”, Bol-zano is ontologically post-archaic and, in particular, related to the Aristotelian no-tion of substance. Consequently, if the stoic propositional logic can dispense from any supporting engagement toward the reality assuming a decisively formalistic and operative mark, the same does not happen for the Bolzanian formal logic which, while not engaging the ontological point of view, is forced to account, on the se-mantic level, the essentialistic realism in background, using a structurally axiomatic configuration and a transfiguration of reality in ideal contents.

Le relazioni della semantica proposizionale di Bernard Bolzano con la logica proposizionale ed enunciativa degli stoici, con particolare riguardo al tema della rappresentazione e al problema del criterio di verità.