Online research in philosophy

The debate over physicalism in philosophy of mind can be seen as concerning an inconsistent tetrad of theses: (1) if physicalism is true, a priori physicalism is true; (2) a priori physicalism is false; (3) if physicalism is false, epiphenomenalism is true; (4) epiphenomenalism is false. This paper argues that one may resolve the debate by distinguishing two conceptions of the physical: on the theory-based conception, it is plausible that (2) is true and (3) is false; on the object-based conception, it is plausible that (3) is true and (2) is false. The paper also defends and explores the version of physicalism that results from this strategy.

The debate over physicalism in philosophy of mind can be seen as concerning an inconsistent tetrad of theses: (1) if physicalism is true, a priori physicalism is true; (2) a priori physicalism is false; (3) if physicalism is false, epiphenomenalism is true; (4) epiphenomenalism is false. This paper argues that one may resolve the debate by distinguishing two conceptions of the physical: on the theory-based conception.

2. The Contingency and A posteriority Constraint: A formulation of the thesis must make physicalism come out contingent and a posteriori. First, physicalism is a contingent truth, if it is a truth. This means that physicalism could have been false, i.e. there are counterfactual worlds in which physicalism is false, for example, counterfactual worlds in which there are <span class='Hi'>miracle</span>-performing angels.[9] Moreover, if physicalism is true, our knowledge of its truth is a posteriori. This is to say that there are ways the world could turn out to be such that physicalism is false. For example, if there are <span class='Hi'>miracle</span>-performing angels, then physicalism is false. So there are worlds considered as actual in which physicalism is false.[10] For short, call this ‘the a posteriority constraint’.[11].

Although 'most contemporary analytic philosophers [endorse] a physicalist picture of the world' (A. Newen; V. Hoffmann; M. Esfeld, 'Preface to Mental Causation, Externalism and Self-Knowledge', Erkenntnis , 67 (2007), p. 147), it is unclear what exactly the physicalist thesis states. The response that physicalism is the thesis that everything is physical does not solve the problem but is a precise statement of the problem because 'the claim is hopelessly vague' (G. Hellman; F. Thompson, 'Physicalism: Ontology, Determination, and Reduction', Journal of Philosophy , 72 (1975), p. 552). I argue that physicalism in fact should be the thesis that every existing particular essentially exemplifies properties the exemplification of which does not conceptually entail the existence of conscious beings. Physicalism thus is a purely philosophical thesis with no intrinsic relation to physics. 1.

Recent discussions of physicalism have focused on the question how the physical ought to be characterized. Many have argued that any characterization of the physical should include the stipulation that the physical is non-mental, and others have claimed that a systematic substitution of ‘non-mental’ for ‘physical’ is all that is needed for philosophical purposes. I argue here that both claims are incorrect: substituting ‘non-mental’ for ‘physical’ in the causal argument for physicalism does not deliver the physicalist conclusion, and the specification that the physical is non-mental is irrelevant to the task of formulating physicalism as a substantive, controversial thesis.

The distinction between token and type physicalism is a familiar feature of discussion of psychophysical relations. Token physicalism, or ontological physicalism, is the view that every token, or particular, in the spatiotemporal world is a physical particular. It is contrasted with type physicalism, or property physicalism -- the view that every first-order type, or property, instantiated in the spatiotemporal world is a physical property. Token physicalism is commonly viewed as a clear thesis, strictly weaker than property physicalism, strictly stronger than substance physicalism, and as a good statement on its own or in conjunction with other theses of minimal physicalism.[i] It is also generally simply assumed to be true, though Davidson has offered a famous argument for its truth, and some have argued against it. Many of those arguing against it are substance physicalists, indicating that they believe token physicalism to be a strictly stronger view.[ii].

This paper is an investigation into the nature of physicalism as well as to the possibility of formulating physicalism as a supervenience thesis. First, I review the motivation for finding a supervenience thesis that characterizes physicalism. Second, I briefly survey the types of supervenience theses that have been proposed as necessary (or, in some cases, as necessary and sufficient) for physicalism. Third, I analyze the recent supervenience thesis proposed by Frank Jackson and expounded upon by Gene Witmer. Jackson claims the supervenience thesis is both necessary and sufficient for physicalism; Witmer has proposed a different interpretation of one of the Jackson’s key notions and has suggested an amended supervenience thesis that is, if not sufficient, at least necessary for physicalism. However, I will argue that neither Jackson’s nor Witmer’s supervenience theses as stated are necessary for physicalism.

Many authors have taken up the challenge of formulating physicalism as a supervenience thesis. These endeavors have met with varying response, but it seems that the general consensus still remains that a supervenience thesis that is both sufficient and necessary for physicalism has yet to be developed. Terence Horgan1 and Jaegwon Kim2 have most famously argued that supervenience theses are not sufficiently strong for physicalism. Nonetheless, several recent articles suggest that there are philosophers who still hold out hope for some type of supervenience of the mental upon the physical being, if not both sufficient and necessary, at least necessary for physicalism.3 In this paper, I will 1) investigate some of the motivation for finding a supervenience thesis that characterizes physicalism, 2) briefly review the types of supervenience theses that have been proposed as necessary (or necessary and sufficient) for physicalism, and 3) investigate in some detail the recent supervenience thesis proposed by Frank Jackson and expounded upon by Gene Witmer. Jackson, in his recent book, claims to have a supervenience thesis that is both necessary and sufficient for physicalism.

Many authors have taken up the challenge of formulating physicalism as a supervenience thesis. These endeavors have met with varying response, but it seems that the general consensus still remains that a supervenience thesis that is both sufficient and necessary for physicalism has yet to be developed. Terence Horgan¹ and Jaegwon Kim² have most famously argued that supervenience theses are not sufficiently strong for physicalism. Nonetheless, several recent articles suggest that there are philosophers who still hold out hope for some type of supervenience of the mental upon the physical being, if not both sufficient and necessary, at least necessary for physicalism.³ In this paper, I will 1) investigate some of the motivation for finding a supervenience thesis that characterizes physicalism, 2) briefly review the types of supervenience theses that have been proposed as necessary (or necessary and sufficient) for physicalism, and 3) investigate in some detail the recent supervenience thesis proposed by Frank Jackson and expounded upon by Gene Witmer. Jackson, in his recent book, claims to have a supervenience thesis that is both necessary and sufficient for physicalism.