The Efficacy of Content: A Functionalist Theory

Abstract

Not all of the problems of mental causation are problems about the mind. Recent work on mental causation has been pre-occupied with a problem which arises if we accept that the physical world is causally closed or ‘complete’ — i.e. that every physical effect is completely fixed by its physical causes alone — and that there are mental causes of physical effects too. How can mental causes have physical effects if those effects are not overdetermined by their acknowledged physical causes, which most parties agree they are generally not? This problem is acute in contemporary theories of mind because they typically deny most versions of a thesis that would solve the problem: an identity theory of mental and physical causes.¹ If mental causes are not identical to physical causes, and there is no massive overdetermination, then it seems we must reject either the causal closure of the physical world or the existence of mental causation.

This paper was presented at the 1996 Utrecht conference on Human Action and Causality, and is derived from talks and lectures given at the University of Mexico City (UNAM), King’s College London, the Universities of Bristol, Hertfordshire, Sussex and Venice (Ca’ Foscari). I am grateful to the participants on these occasions for helpful discussion, and especially to Helen Bee-bee, Michiel Brumsen, Fred Dretske, Frank Jackson, Fraser Macbride, Mike Martin, Brian McLaughlin, Hugh Mellor, David Papineau, Philip Pettit, Michael Smith and Scott Sturgeon for useful comments.

For an account of this problem, see Crane (1995).