Manuel I Komnenos and Michael Glykas: A Twelfth Century Defense and Refutation of Astrology

Manuel I Komnenos and Michael Glykas: A Twelfth Century Defense and Refutation of Astrology

By Demetra George

Culture and Cosmos, Vol.5-6 (2001-2002)

Abstract: Manuel Komnenos I, Emperor of the Byzantine Empire composed a defence of astrology to the Church Fathers, in which he asserted that this discipline was compatible with Christian doctrine. Theologian Michael Glykas, possibly imprisoned and blinded by Manuel for political sedition, refuted this defence, claiming that the astrological art was heretical. This is the first time that this exchange of treatises has been translated into any language since their composition in the twelfth-century. The introduction sets these works into their historical framework, at a time when the belief in the validity of astrology was held by some of the best scholars of this century as a result of the flood of Arabic astrological translations coming into the Latin West and Greek East. The writings of these two antagonists precipitated anew in mediaeval thought the problem of the correct relationship between man, the celestial bodies and God who dwelled in Heaven.

Introduction: Manuel I Komnenos, emperor of the Eastern Byzantine Empire from 1143-1180 wrote a public defence of astrology to the Church Fathers, integrating his belief in the astrological science with Christian doctrines. Michael Glykas, a monastic theologian, responded to this letter with a famous refutation. While Manuel’s astrological defence, aside from legislation and dialogues in which he is featured, is his only surviving document, this is the first time that it, as well as Glykas’ refutation, have been translated from the Greek since their composition in the twelfth century. The lack of academic interest in these two tracts points to the marginal position in which historians have placed the field of astrology as a body of knowledge in the Middle Ages. However as Lemay asserts, ‘It has always been a great mistake of historians of mediaeval thought to minimize or to totally overlook this field of inquiry as of no importance or as having negligible bearing on the intellectual outlook of the time’.

The first part of this introduction presents an overview of the historical development of astrology in antiquity faced with the continual opposition from both pagan philosophers and Christian writers. The debate that takes place between Manuel and Glykas over the validity and legitimacy of astrology was not an isolated twelfth century exchange between an emperor and a monk, but the continuation of a long tradition of controversy over what was the proper relationship between the divine and the stars. The question of whether a belief in astrology constituted heresy was at the core of their dispute, and the significance of what transpired between Manuel and Glykas can best be comprehended when placed within a larger historical context.

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