The topics in medieval logic

Abstract

The topics is a theory of argumentation based upon topoi or in Latin loci. The medieval logicians used works by Aristotle and Boethius as their sources for this doctrine, but they developed it in a rather original way. The topics became a higher-level analysis of arguments which are non-valid from a purely formal point of view, but where it is none the less legitimate to infer the conclusion from the premiss(es). In this connection the topics give rise to a number of discussions about the form and the matter of arguments. Further the topic contribute to the elaboration of the important doctrine of the second intentions, i.e. higher-level concepts of the particular things. In some respects the topics may be said to form a link between formal and informal logic. The topics vanished as a part of logic at the end of the Middle Ages, perhaps because the medieval logicians never got rid of Boethius' claim to have compiled a complete list of the loci, which was an unlucky one. The topics does not have an exact parallel in modern formal logic, but some reflections on non-formal argumentation by recent authors contain certain resemblances to it.