Abstract

This work is a study of the place of conscious experience in the natural order. In the first part, I examine the prospects for a reductive explanation of consciousness of the kind that has proved successful for other natural phenomena. I develop a systematic framework centered on the notion of supervenience for dealing with the metaphysical and explanatory issues involved, and apply this framework to consciousness. I give a number of arguments to the conclusion that consciousness is not logically supervenient on the physical, and therefore cannot be reductively explained. I illustrate this with a critique of potential explanations using the methods of cognitive modeling, neuroscience, and evolutionary biology. I further argue for a form of dualism, on which consciousness is seen as a non-physical property that supervenes on the physical by a lawful connection. In the second part, I move toward a positive theory of consciousness, focusing on the nature of the laws that connect consciousness and the physical. I deal at length with the relation between consciousness and judgments about consciousness; this provides a nexus between consciousness and cognition that can be exploited to strongly constrain a theory. In addition, I provide and analyze thought-experiments in arguing for the conclusion that any two systems with the same abstract functional organization will have the same conscious experience, and so arguing against what have been called the "absent qualia" and "inverted qualia" hypotheses. Finally, I briefly outline some further work: a double-aspect theory of consciousness based on the notion of information, an investigation of the relationship between computation and consciousness, and an application to some problems in quantum mechanics