Apocalyptic Calculators of the Later Middle Ages

medieval astrology

medieval astrology

Apocalyptic Calculators of the Later Middle Ages

Laura Smoller (University of Arkansas at Little Rock)

Paper given at the 3rd Annual Conference of the Center for Millennial Studies (1998)


The purpose of my talk today is to explore why and how astrology became an accepted tool for apocalyptic calculation in the later Middle Ages. Although thirteenth-century scholars flirted with the idea of using the stars to calculate the timing of the end, serious astrological calculations of the apocalypse began in earnest only in the early fifteenth century, during the pervasive, eschatologically-charged crisis of the Great Schism of 1378 to 1414. Scholars then began to look to the stars, I will argue, as an outside, scientific means of countering urgent apocalyptic predictions based on prophecies, visions, and the interpretation of Scripture, predictions that in many instances were coming to be seen as dangerous and divisive. Once astrological calculations were incorporated into the eschatological arsenal, however, they began, rather, to add fuel to apocalyptic fires, complementing, rather than quashing more traditional modes of speculation.

In the twelfth and thirteenth centuries, large numbers of astrological texts had entered Europe, Latin translations of ancient Greek and, more importantly, medieval Arabic writings on the stars. Particularly in the works of Arabic astrologers, European scholars encountered theories that would give the stars a role in major religious changes and in delineating large periods of world history. These theories would underlay astrological calculations of the timing of the End. A poem began circulating in the thirteenth century, for example, falsely attributed to the Roman poet Ovid that made use of the theories of the ninth-century Arabic astrologer Abu Ma’shar. In this poem, “Ovid” correlates the birth of religions, including Christianity, with certain periodic conjunctions of the planets Saturn and Jupiter. Just as these religious changes had been written in the stars, the arrival of Antichrist would be, as well. Probably no one in the thirteenth century more eagerly embraced the possibilities of using astrology to investigate the apocalypse than did the Franciscan Roger Bacon. In his circa 1266 Opus maius, addressed to Pope Clement IV, Bacon championed Abu Ma’shar’s theories about planetary conjunctions and religious change.

Click here to read this article from the Center for Millennial Studies

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