Reading God´s will in the stars. Petrus Alfonsi and Raymond de Marseille defend the new Arabic Astrology

Abstract

Petrus Alfonsi and Raymond of Marseille both attempt to justify the theory and practice of astrology in the face of considerable skepticism and opposition. They aggressively defend the art of celestial divination, affirming that it is part of God's rational plan for the universe. They attack their opponents (both practitioners of inferior astrology and clerical opponents of astrology) as (inter alia) blind, perverse, irrational beasts. Their polemics shed light on the reception of Arabic, science in Latin Europe in the first half of the twelfth century and on the invocation of "reason" (ratio) as an increasingly popular rhetorical weapon.