This book aims to provide an interpretation of several aspects of the philosophical system that William of Auvergne (1180-1249) – bishop of the city of Paris and councilor of Louis IX – developed in a cultural context wherein the Latin world had a special interest in Greek, Arabic, and Hebrew sources. The author focuses on issues relative to the causality of God and astrological causality, fate and providence, miracles and mirabilia, the conception of man as a nexus and as a divine image, the doctrine of beauty and of music. All these combine in outlining the profile of a thinker who stands as a milestone in the history of the critical tradition of Aristotelianism until the eve of modernity.