Marsilius of Inghen on the Definition of consequentia

This paper offers an analysis of Marsilius of Inghen’s definition of consequentia and of his treatment of logical validity as presented in the first book of his treatise on Consequentiae. Comparing Marsilius of Inghen’s, John Buridan’s, and Albert of Saxony’s theories, the author argues that Marsilius’ account is based on a conception of consequence as a relation of entailment among propositions rather than as a type of conditional sentence and, thus, moves the discussion away from the sentential level. Therefore, Marsilius’ theory represents an original and important contribution to fourteenth-century discussions on consequences.