In this chapter, we review the earliest phase of medieval logic in the Latin West, from its modest first beginnings in the eighth century to its full elaboration as a subject field in the twelfth. The manuscript evidence from this extended era is incomplete, and often in a preliminary state of scholarly consolidation; so the historical account based on these materials is necessarily limited. Indeed, the very attempt to construct hypotheses about lineage and association may prove counter-productive in some cases, especially in the period prior to the eleventh century. In the eighth and ninth centuries the approach to logic in the Latin West is largely Platonist and metaphysical in character. This subsequently gives way to a more linguistically oriented study, in which we find the onset of creative investigation into inferential relations between categorical and hypothetical statements, and (somewhat later) into sentential relations between subjects and predicates. St. Anselm in the eleventh century is an eminent contributor to this tradition, followed by Peter Abelard and other notable masters of the twelfth-century Logico-Philosophical Schools (such as Gilbert of Poitiers). This final century is shaped by the vocalist/nominalist controversies, and by the recovery of major logical works of Aristotle; it is a time of great ferment.

LATE EIGHTH- AND NINTH-CENTURY PRECURSORS

The medieval era's productive involvement in the field of logic begins with the educational reforms of the Carolingian period. Alcuin of York (c. 720–806) is the central figure in these reforms. After a period of study in York, Alcuin was invited by Charlemagne to teach at the Carolingian court in Aachen in the late eighth century. He used his formidable influence as an advocate for the arts of the Trivium: grammar, rhetoric and logic. Among his many writings, we find separate treatises on each of these subjects; among these, the one on logic – De dialectica – has some claim to being the point of departure for medieval work in Latin in this area.

This treatise is a brief conspectus of the field of logic as it was understood in Alcuin's time. There is not much addition to knowledge attempted here (and indeed, the text itself is largely copied from sections of Isodore's Etymologiae, which themselves derive from Cassiodorus’ Institutiones); the point is simply to identify the divisions of logic and indicate the content of each.