Abstract

The subject of the present article is the analysis of fundamental logical-semantical terminology of late-medieval nominalistic logician Jean Buridan (c. 1295–1360). The analysis focuses on the concepts of truth conditions and logical consequence, whose clarification presupposes explication of modal terminology as well as a solution of semantical antinomies such as “Liar” (or an attempt to solve them). The analysis of Buridan’s argumentation suggests that Buridan’s project of logic actually fails due to several failures of conceptual analysis of semantical and modal terminology. An alternative solution of the question concerning logical consequence is thus proposed in terms of Buridan’s implicit (and unused) semantical conception of modalities that makes it possible to establish conceptually and therefore explicatively closed logical framework.