Daniel De Haan

Hosts: Therese Cory, Stephen Ogden

Dr. Daniel D. De Haan is the Frederick Copleston Senior Research Fellow & Lecturer in Philosophy and Theology in the Catholic Tradition at Blackfriars and Campion Hall, Oxford University. His research focuses on philosophical anthropology, philosophy of religion, and medieval philosophy especially in the work of Thomas Aquinas and Avicenna. He is the author of Necessary Existence and the Doctrine of Being in Avicenna’s Metaphysics of the Healing (Brill, 2020).

During my stay at the University of Notre Dame I will be working on my monograph on the problem of human knowledge of singulars in St Thomas Aquinas. This book builds upon my past research on the vis cogitativa in Aquinas by focusing on objections to his account of human rational knowledge of material singulars, and the implications these objections have for his metaphysics of mind and arguments for the immateriality of the rational soul. Aquinas's solution to the problem suggests that humans cognize singulars through the coordination of their intellectual and cogitative powers. One major difficulty with this answer is it does not seem to explain how humans achieve intellectual cognition of material singulars if the power of intellect and all intellectual operations remains in the dark concerning the merely potentially intelligible material individuals and phantasms cognized by sensory powers like the vis cogitativa. During my time at Notre Dame's History of Philosophy Forum I also intend to explore why Aquinas and his predecessors adopted models of the mind that focused on the distinction between individuality and universality as the primary contrast between sensation and reason. What principles and arguments do they find in Aristotle or other predecessors that support their contentions that the intellect cannot cognize material individuals? Why not focus instead on features like definition, truth, logical forms, and rational normativity as the defining features of the mind that contrast it from sensory powers? Features that would permit them to preserve the obvious fact that humans can mind individuals. One answer I intend to explore is the connection these positions have to Aristotelian-style arguments for the immateriality of the intellect, since two of Aquinas’s arguments for the mind’s immateriality rely upon the intellect’s ability to cognize everything (omnia) and universals.

Affiliation: University of Oxford