The logical operation of division by John of Damascus and Nicephoros Blemmydes

Abstract

The article examines the influence of Aristotle's logic, the methods of definition and division on Byzantine thought. For analysis, we have chosen two of the most popular textbooks on logic in Byzantium, which belong to John of Damascus and Nikephoros Blemmydes. St. John of Damascus (c. 675 - c. 750) in his "Source of Knowledge" constantly and actively uses logical methods, in particular, dichotomous division, analyzing in detail what was later called the Tree of Porphyry. In violation of the principle of dichotomous division, when dividing the animate, he gets three concepts: animals, zoophytes and plants. The article shows that these and other features in his presentation of the division operation go back to the late Neoplatonists, whom he does not name, though. The work of Damaskus was soon translated into Latin, and later repeatedly translated into Slavic and Russian, contributing to acquaintance with the logic of Aristotle and the emergence of logical terminology in Rus'. Unlike the work of Damascus, the work of the famous Byzantine scholar Nicephoros Blemmydes (1197–1272) has not yet been translated from Greek into any of the modern languages ​​and remains little studied. In this article, we analyze two chapters of his "Logic" devoted to the logical operation of division and the analysis of the Porphyry tree. Some differences in the usual presentation of the Porphyry tree are also revealed in the compendium of Nicephoros Blemmydes. Nicephoros Blemmydes does not deviate from the principle of dichotomous division: he combines zoophytes and plants into one category of non-moving ones, while removing the division of rational beings into mortals and immortals.