Abstract
The paper defends Functionalism against the charge that it would make mental properties inefficacious. It outlines two ways of formulating the doctrine that mental properties are Functional properties and shows that both allow mental properties to be efficacious. The first (Lewis) approach takes functional properties to be the occupants of causal roles. Block [1990] has argued that mental properties should not be characterized in this way because it would make them properties of the ?implementing science?, e. g. neuroscience. I show why this is not a problem. The second way of formulating the doctrine takes functional properties to be causal role properties. I claim that mental properties so understood would only be inefficacious if a law-centred rather than a property-centred approach is adopted to the introduction of efficacy into the world. I develop a property-centred account that explains how mental properties can be efficacacious without introducing systematic overdetermination. At the close, I provide a better characterization of the difference between these two approaches and offer an explanation as to why my way of resolving the problems has been missed