This thesis presents an argument that would posit a substantial non-physical principle of cognition and consciousness, i.e . a mind or soul, ontologically distinct from the physical brain and its properties. The case consists of, first, a series of arguments that seek to establish the rational foundation for this Cartesian or substance dualism and, second, an attempt to reply to some of the major objections to it. The second component includes a survey of physicalism , the chief alternative to dualism as a solution to the classic mind-body problem. The theological significance of the debate, and particularly of the status one accords to dualism in the debate, is the concern of the final chapter. The latter concludes that the implications of...