O Conceito Megárico e Aristotélico de Possibilidade

Uma contribuição para a história do problema ontológico das modalidades

Abstract

In this article, the German philosopher Nicolai Hartmann (1882-1950) goes in detail through the clash in Hellenistic Antiquity about the modalities of logic. The best known in the Western world is Aristotle's version, centred between act and potency. This version was widely discussed and applied by Christian Scholasticism in Europe, and spread to the Modern’s developments and rejections of Aristotelianism. However, Hartmann recovered an old logic, contemporary to Aristotle himself, and which was opposed to him: the School of the Megarians, founded by Euclid of Megara, a former disciple of Socrates. The apparent equivalence between act and potency – or rather, actuality and potentiality – came to be very well developed by the rivals of the Aristotelian schools, especially by Diodorus Cronus and the Greek Stoics. However, far from being a mere equivalence, Hartmann recovers and develops this categorical pair towards new directions that are very interesting for contemporary ontology and for the modal logic of the last decades.