In Defense of A Posteriori Minimal Physicalism

The aim of this dissertation is to defend a version of a posteriori minimal physicalism which claims that everything including phenomenal consciousness supervenes globally logically on the physical. The view is 'minimal' since it is intended to capture the minimal commitment of all kinds of physicalism. The view is 'a posteriori' since it does not require that everything necessitated by the physical needs to be a priori necessitated by the physical. It holds that being in pain is necessitated by the physical, but not a priori necessitated. In this dissertation I consider and address three main objections to this thesis. I aim not to change the premises of opponents but to show that minimal physicalism is a viable option by developing a way of explaining away the seeming contradictions.;The first objection I consider is a descendent of the traditional conceivability argument. It is claimed that physicalists must be committed to the view that zombie worlds are not possible, since they hold that the mental at least supervenes on the physical. David Chalmers claims that we can conceive of a zombie world, and argues that ideal primary positive conceivability entails metaphysical possibility. Therefore, he contends, a zombie world is possible. I respond by arguing that his ideal primary positive conceivability does not entail the metaphysical possibility of a situation that we need and that he cannot ideally positively conceive of a zombie world which is a minimal physical duplicate of ours.;The second objection that I consider is the a priori deducibility argument that is supported by entry-by-entailment thesis. Frank Jackson and David Chalmers argue that supervenience thesis entails an a priori entailment thesis and that the logical supervenience of the mental on the physical implies a priori deducibility of the mental from the physical. Thus, they claim that a rich enough story about the physical nature of our world must a priori entail the psychological story about our world. I respond by arguing that the judgment they introduced for the argument is not a priori but a posteriori, and that a rich enough story about the physical nature of a world cannot give us the relevant contextual information that we need for a priori deduction. I also argue against the a priori deducibility argument by claiming that contingent a posteriori contextual information that links the physical to the psychological cannot be included in a rich enough purely physical story about a world.;The third objection that I consider depends on Kripkean modal argument refined by two-dimensionalism. It is widely accepted that physicalism has modal commitments. According to this objection, contrary to scientific discoveries which are necessary a posteriori, the appearance of contingency between the mental and the physical, whether the relation is identity or supervenience, are real, since the relation between the mental and the physical is not secondarily necessary. I exploit the notion of global logical supervenience which I provide in earlier chapters, and develop a way of explaining away the appearance of the contingency of supervenience. I conclude that any form of identity thesis cannot be sustained, but that a posteriori minimal physicalism, based on supervenience thesis, can be maintained.;The discussion of these three objections together with humean supervenience thesis suggests that there is no room for the mental to merely naturally supervene on the physical. If what Chalmers claims is that we seem be able to conceive ideally positively of a situation in which the laws of nature fail to obtain in some minimal physical duplicate of our world, then it does not entail that the situation is metaphysically possible. If the laws of nature globally logically supervene on the physical, and consciousness globally naturally supervenes on the physical, then consciousness also globally logically supervenes on the physical.