COMMONSENSE FACULTY PSYCHOLOGY: REIDIAN FOUNDATIONS FOR COMPUTATIONAL COGNITIVE SCIENCE (FUNCTIONALISM, INTENTIONALITY, MODULARITY, MIND, REPRESENTATION).

This work locates the historical and conceptual foundations of cognitive science in the "commonsense" psychology of the philosopher Thomas Reid. I begin with Reid's attack on his rationalist and empiricist competitors of the 17th and 18th centuries. I then present his positive theory as a sophisticated faculty psychology appealing to innateness of mental structure. Reidian psychological faculties are equally trustworthy, causally independent mental powers, and I argue that they share nine distinct properties. This distinguishes Reidian 'intentionalism' from idealist 'representationalism,' which derive cognitive content either from the inherited structure of faculties of from the occurrent structure of sensory activity. Next, I turn to consciousness and reflection for a contemporary Reidian response to traditional phenomenology. Unlike reflection, faculties of reason and remembrance are not causally mediated by consciousness. My interpretation of Reid is that 'Humean causation' of individual faculty structure accounts only for 'natural intentionality,' while 'efficient causation' of faculty interrelations accounts for cognitive 'personal intentionality.' I then proceed by adopting a form of computational description for reconstructing this view as a computational theory of mind. I contrast functional analyses in explanations of some capacities with computational and componential analyses in explanations of other, intentional capacities, in which some processes must be taken to semantically encode and govern the roles of others. This step reconstructs the Reidian notion of intentional operations as requiring an explanation of component faculties and their representation-governed interactions. I argue that properties of faculties delimiting these interactions under Reid's theory parallel those in Fodor's (1983) essay on the "modularity of mind," although the reasons given for individual criteria are often very different. Fodor also proposes a trichotomous mental structure, but I find that a third level of "central systems" is a myth engendered by causal information theory. Such an analysis cannot capture generalizations over the internal representation of semantic roles that determines the character of faculty relations. This requirement for any computational account of cognition is precisely the motivation for the reconstructed Reidian theory. Thus, it comports more favorably with the explanatory program constitutive of a computational cognitive science