I argue that physicalists have been too conciliatory in granting that certain classic thought experiments about consciousness like Mary the colour scientist, colour spectrum inversion, and zombies provide strong prima facie support for epiphenomenal anti-physicalism. While these thought experiments may suggest that we are intuitive epiphenomenal anti-physicalists when taken individually, when they are appropriately combined, they suggest that epiphenomenal anti-physicalism leads to a version of phenomenal scepticism according to which (i) we cannot know how our states of phenomenal consciousness compare (...) and contrast and (ii) we cannot know how our first-order beliefs about our states of consciousness compare and contrast. Insofar as comparative phenomenal scepticism is a deeply counter-intuitive view, our intuitions about consciousness are far more equivocal than they are widely thought to be. There simply may be no one metaphysical view that should qualify as their obvious champion. (shrink)

Both a priori physicalism and a posteriori physicalism combine a metaphysical and an epistemological thesis. They agree about the metaphysical thesis: our world is wholly physical. Most agree that this requires everything that there is must be necessitated by the sort of truths described by physics. If we call the conjunction of the basic truths of physics P, all physicalists agree that P entails for any truth Q. Where they disagree is whether or not this entailment can be known a (...) priori. The a priori physicalist says it can, the a posteriori physicalist says it cannot. Though a posteriori physicalism is probably the dominant view, it is really a surprising and somewhat unlikely stance. In this article, the nature of the view is discussed, and two arguments are presented that should cause us to look again at the potential of a priori physicalism. (shrink)