Abstract

It is clear that there is a problem of consciousness; it is less clear what that problem is. In chapter one I discuss what it might be, bracket off some especially intractable issues, and present two central questions. First, what is the nature of consciousness? Second, what are the prospects for producing consciousness in machines? I then look at various ways one might approach these questions. ;Chapter two focuses on the nature of consciousness. My definition of consciousness centers on qualia, a concept that I discuss in detail. I show that consciousness can be thought of as having three aspects: intransitive creature consciousness, transitive creature consciousness, and state consciousness. The relations between these three facets are explored. ;Chapter three expands on two issues raised in chapter two. First, I argue that qualia are present not just in sense perception but also in ordinary propositional thought. Second, I contrast my definition of consciousness with other common definitions. I show that some of these reduce to qualia-based theories similar to mine, while others lead to problems severe enough to suggest that they should be abandoned. ;Chapter four deals with machine consciousness by looking carefully at the Chinese room argument and at connectionist models of cognition. I support the Chinese room's conclusion that the running of a program is insufficient for producing consciousness, and I argue that the possibility of machine consciousness hinges on our ability to identify and replicate the causal mechanisms that produce it in humans. ;My theory has implications for a variety of philosophical questions. These implications are explored in a somewhat speculative manner in chapter five. I discuss how consciousness affects our efforts to solve the mind/body problem; I assess possible strategies for recognizing consciousness in other systems; and I examine connections between consciousness and personhood, focusing on the issues of personal identity and personal rights. ;Instead of developing a single line of thought or argument in this dissertation, I present a collection of ideas and arguments which, although not tightly integrated, do provide mutual support and contribute to a single overarching theory of consciousness