Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!ucsd!rutgers!elbereth.rutgers.edu!harnad From: harnad@elbereth.rutgers.edu (Stevan Harnad) Newsgroups: comp.ai Subject: On Epiphenomenalism Keywords: Against Dualism [re: Searle's Chinese Room Argument] Message-ID: Date: 6 Mar 89 06:32:14 GMT Organization: Rutgers Univ., New Brunswick, N.J. Lines: 49 So far, few (perhaps none) of the responses to my postings about Searle's Chinese Room Argument have shown evidence of having adequately understood either Searle's arguments or my own. In fact, even those that might appear to some readers to have been the most sympathetic to some of the points I was making (particularly the points about subjectivity) seem to be far from the mark. I am accordingly posting the following clarification about dualism and the status of subjectivity in the approach to cognitive modeling that I am advocating. METHODOLOGICAL EPIPHENOMENALISM VS. METAPHYSICAL EPIPHENOMENALISM The difference between "methodological epiphenomenalism" (MTE) and "metaphysical epiphenomenalism" (MPE) is this: MTE accepts that subjectivity exists, is real, and CANNOT BE SHOWN TO BE the same as any physical structure or process. According to MTE, we should simply accept this as an unavoidable constraint of cognitive modeling and accordingly restrict ourselves to the sole methodologically feasible strategy: To attempt to model only the objective data -- first, our (total) performance capacity (the TTT), then perhaps fine-tuning it to include the relevant details of our brain's "performance" (the "TTTT"). The rest would just be hermeneutics (overinterpreting our models) anyway, because of the "other minds" problem. MPE accepts that subjectivity exists, is real, and IS NOT the same as any physical structure or process. As such, MPE is a form of dualism, although it agrees with MTE that subjectivity has no independent causal power; only physical structures and processes have causal power. The various forms of reductionism (the "identity" theories, "functionalism," etc.) are NOT epiphenomenalist: They give arguments (lousy ones, in my opinion) to try persuade you that subjective states are really the same thing as certain objective states (for identity theory, certain brain states -- for functionalism, certain formal states). Unsatisfied with these arguments, MPE bites the bullet on dualism, whereas MTE points out that there's no practical reason for a cognitive theorist to commit himself one way or another, or even to worry about it, from here to theory-complete eternity. I advocate MTE and am agnostic about MPE. Ref: Harnad S. (1989) Minds, Machines and Searle. Journal of Experimental and Theoretical Artificial Intelligence" 1: 5-25 -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771