Dialectic is a standard and important part of the logica vetus (or old logic) in medieval philosophy. It has its ultimate origins in Aristotle's Topics,its fundamental source in Boethius's De topicis differentiis,and its flowering in its absorption into fourteenth-century theories of consequences or conditional inferences. The chapter on Topics in Garlandus Compotista's logic book is the oldest scholastic work on dialectic still extant. In this paper I show the differences between Boethius's Theory of Topics and Garlandus's in (...) order to illustrate the role of Topics in early scholastic logic. I argue that for Garlandus Topics are warrants for the inference from the antecedent to the consequent in a conditional proposition and that he is interested in Topics because of his overriding interest in hypothetical syllogisms. I conclude by discussing briefly the relationship between Garlandus's use of Topics and twelfth-century accounts. (shrink)

This work is essentially a history of the scholastic conception of dialectica from Garlandus Compotista to William Ockham, with an eye to rendering intelligible the puzzling nature of late medieval treatises on logical obligations. Such treatises seem to countenance violations of fundamental and indisputable logical rules, for example, that a disjunction is false if both of its disjuncts are false. In large part to explain this apparent surd development in medieval logic, Eleonore Stump has collected into a single (...) volume twelve separately published essays. Together they form an interesting and convincing argument. (shrink)