Abstract
On the eve of the Middle Ages, slightly more than one century after the fall of the Western Roman Empire, in Spain under Visigothic rule Latin was still the language of culture and everyday spoken communication. In Seville, the bishop Isidore wrote what was to become the reference encyclopedia of the Middle Ages, the Etymologiae, whose very title indicates that speculation about etymology is key to the treatment of all disciplines, from mathematics to theology. This enormously influential treatise established a canon of disciplines and authors that was to last for almost a millennium. As an etymologist, by the standards of modern research Isidore does not count as a full-fledged colleague: he pursues the method adopted in Latin antiquity in Varro, but with less insight than Varro into the mechanisms of language per se. Nonetheless, the Etymologiae are a fascinating cultural object, with speculation on language one of its prime ingredients.