Between 1100 and 1500 the scholastic philosophers composed about 95 commentaries on the topics. These works concern Aristotle's Topics and Boethius' De Differentis Topicis which together with Boethius' In Ciceronis Topica exerted a significant influence upon the development of medieval logic. Boethius and the medieval authors pay great attention to the question what a locus (topos) is. The function of the locus is described in connection with all the inference-forms which were known to the medieval logicians, viz. categorical and hypothetical syllogism, enthymemes, consequences, the modus ponens and the modus tollens. Boethius is the first author from whom we know the concept of the maxim. Both in the commentaries and in the medieval manuals of logic, for example, of Abelard, Albert the Great, William of Sherwood, Ockham and Buridan, discussions of the topics connect with and contribute to several important logical and philosophical debates, such as those about dialectic, the theory of argumentation, axiomatics, formalism, universals, modal logic, and the theory of consequences, as well as the distinctions between object- and meta-language, inventio and iudicium, and first and second intentions. The discussions in this volume therefore mainly concern the philosophy of logic, which constitutes a uniquely thorough and original treatment of an important logical tradition. The volume contains a catalogue of the commentaries which are known to exist and an appendix of hitherto unprinted texts. Of interest to: Philosophers, logicians, linguists, theologians, historians of these disciplines, researchers in medieval studies