Noble Soul and the Metaphysics of Celestial Life in the Liber de causis Commentaries of Albert the Great, Thomas Aquinas, and Giles of Rome

The Liber de causis, from 9th-c. Baghdad describes three primary causes of the universe: the first cause, intelligence, and noble soul. The first cause is the source of all existence, intelligence the source of all form, and noble soul the origin of life motion in bodies. This third primary cause, noble soul, sparked a tradition of interpretation in the Latin West that existed from the 12th-16th centuries and includes understandings of that concept as diverse as the conclusion that it is human soul, celestial soul, world soul, an angel, and even the Holy Spirit. This dissertation describes the foundational moment of that history in the commentaries of three masters of theology in Paris in the 13th c., Albert the Great, Thomas Aquinas, and Giles of Rome. Through these three commentators, noble soul is drawn into the celestial metaphysics of the Peripatetics, then set against the background of the Platonic tradition, and finally subsumed within the celestial hierarchies of Ps.-Dionysius the Areopagite. Albert the Great offers one of the first interpretations of noble soul as a celestial mover after readers from the 12th c. tended to understand that concept as human soul (Ch. 1). Albert incorporates noble soul into his understanding of the tradition of Arabic celestial metaphysics using the concept to resolve tensions between Peripatetic authorities and to articulate the perfection of Aristotelian metaphysics. For Albert, noble soul’s celestial office ultimately belongs to the larger metaphysical framework of emanative causality called fluxus which he bases on the writings of Alfarabi, Avicenna, and Algazel (Ch. 2). In this system noble soul becomes a necessary part of the process by which the light of the first cause flows into all of reality. Thomas Aquinas is the first to demonstrate the dependence of the De causis on Proclus’ Elements of Theology, and in his commentary, noble soul becomes part of an effort to clarify the Platonic doctrines of the forms and participation and to correct them through Aristotle and Ps.-Dionysius (Ch. 3). Thomas remains skeptical about the existence of noble soul but uses the concept as an opportunity to develop an understanding of participation that incorporates aspects of the Platonic doctrines into a Dionysian metaphysics of creation. Giles of Romes takes up Thomas’ engagements with platonic doctrine to develop his own understanding of contractio—the dynamic by which all created essences participate the being bestowed on them by the first cause (Ch. 4). This contraction of being unfolds in a hierarchy of creatures in which noble soul plays the role of mediator between the orders of separate intelligences and bodies. Noble soul’s role as mediator depends on Giles’ understanding that the primary causes of the Liber de causis belong to the angelic hierarchies of the Christian faith (Ch. 5). Giles thereby interprets noble soul’s celestial operations through the principles of Dionysian hierarchy and so doing also provides the metaphysical basis by which he will later articulate his theory of papal power.