Argument against non-reductive physicalism Jaegwon Kim

figure demonstration how m1 , m2 not reduced p1 , p2.

kim has raised objection based on causal closure , overdetermination non-reductive physicalism.

the non-reductive physicalist committed following 3 principles: irreducibility of mental physical, version of mental-physical supervenience, , causal efficaciousness of mental states. problem, according kim, when these 3 commitments combined few other well-accepted principles, inconsistency generated entails causal impotence of mental properties. first principle, ontological physicalists accept, causal closure of physical domain, according which, every physical effect has sufficient physical cause. second principle kim notes of causal exclusion, holds no normal event can have more 1 sufficient cause. problem behavior cannot have cause, both physical event , (supervening) mental event, without resulting in case of overdetermination (thus violating principle of causal exclusion). result physical causes exclude mental states causally contributing behavior.

in detail: proposes (using chart on right) m1 causes m2 (these mental events) , p1 causes p2 (these physical events). m1 has p1 supervenience base, , m2 has p2 supervenience base. way m1 cause m2, causing supervenience base p2 (a case of mental-to-physical causation). if p1 causes p2, , m1 causes p2, have case of causal overdetermination. applying principle of causal-exclusion, either p1 or m1 must eliminated cause of p2. given principle of causal closure of physical domain, m1 excluded.

the non-reductive physicalist forced choose between 2 unappealing options: 1 reject causal-exclusion principle , claim in scenario dealing genuine case of overdetermination, or 1 embrace epiphenomenalism. kim argues mental causation can preserved rejecting premise of irreducibility in favor of reduction; in order mental properties considered causally efficacious, must reducible physical properties.