The nature of consciousness is fundamental to the philosophy of mind and cognitive science. However, the "difficult problem" - the issue of how first-person experience, and the raw feel of awareness can accompany the physical processes of neurobiology - remains intractable. A crucial aspect of this problem in the philosophy of mind is the question of ontology. Does mind or consciousness exist as a real feature of the world? Between materialism and dualism, which (if either) of these basic theories is true is an issue that is crucial to the way we understand normal and pathological human cognition, and the nature of the psyche. The data of parapsychology has direct relevance to these and other issues in cognitive science. Besides promising approaches to the "other minds" problem, and possible applications to the evolutionary origins of consciousness, the greatest contribution of parapsychology consists in what it has to say about materialism vs. dualism. Some of the implications of parapsychological research are very telling against the sufficiency of materialism as a framework within which to explain consciousness. The paper concludes with major problems which parapsychology must address to flesh out its contribution to ontology.