Abstract

According to Thomas Aquinas, human beings are metaphysical amphibians: they live both in the corporeal world of rocks and trees and in the immaterial world of the intellect. This unusual status is due to the rational soul, which is the substantial from of the human body and able to transcend that body through abstract thought. Aquinas holds that the human soul is not a substance, and that a human being is not identical to her soul. Taken together, these claims commit Aquinas to the denial of a strong from of substance dualism. ;These claims raise difficulties for Aquinas's accounts of individuation and identity, however, when taken in conjunction with his belief that, at death, the soul persists in separation from matter until the bodily resurrection. If matter is necessary for individuation, how can human souls remain individuated in separation from material bodies? Further, if the human being is not identical to the human soul, the existence of the disembodied soul constitutes a gap in the continuity of the human being. How, then, can the resurrected human being be numerically identical to the original human being? ;In the dissertation, I examine and evaluate Aquinas's claims about the individuation and identity of human beings, and I argue that his account of human nature is more promising than philosophers from Suarez to Swinburne have traditionally agreed. ;My defense of Aquinas has three main stages: first, I address Aquinas's general theory of individuation ; I argue that this theory is both coherent and philosophically plausible. Second, I address the individuation of disembodied human souls---I claim that souls remain individuated in separation from matter by a continuing relation to their bodies. Third, I argue that although Aquinas's theory of human identity is problematic, the contemporary notion of immanent causation allows us to understand the separated soul as guaranteeing that the appropriate causal relations hold between the original and the resurrected human being