My reading the last few days has generally been drawn from ‘The Possible and the Actual: Readings in the Metaphysics of Modality‘, and ‘Philosophy of Mind: Contemporary Readings‘. A few notes on the former and latter:
– Regarding modality, I generally took it for granted that modalities are, as it were, ‘built-in’ to reality. An interesting thesis I read, however, by Nicholas Rescher, is that possibilities of the modal variety are mind-dependent. That is, what Rescher calls ‘hard core’ possibilities – possibilities that are totally unactualized – exist only in the mind conceptually. This took me for a bit of a loop, because how good modality be mind-dependent? Surely possibility has to be a real feature of the real world. But then I thought a bit harder – perhaps by distinguishing possibility from contingency, the former having to do logical necessity and the latter having to do with metaphysical non-necessity. Keeping that distinction in mind, modal idealism isn’t so farfetched sounding. Modal possibility can exist firmly within the mind while metaphysical contingency can exist firmly within the real order of things. If, however, one were to take Plantinga’s line of actualism, in which possible worlds are constructed out of states of affairs, then modal idealism wouldn’t have as much appeal. An interesting line in Rescher’s argument is geared towards denying any kind of Platonic ‘space’ for possibilities to exist in outside the natural order – so if one took a slightly Platonic line, then modal idealism would indeed be rather senseless.
– Regarding philosophy of mind, I guess it never occurred to me that functionalism, if true, functions (haw haw) as an argument against reductive physicalism, which is a little funny because, as is well known, functionalism is a materialist theory of mind – this seems to be fairly well known in the literature, though, and I’ll chalk this one up as my own lack of thinking it through. Multiple realization (or realize-ability) also seems to pose a threat to more reductive flavours of physicalism, but I’m not quite sure I have a good enough grasp on MR to really come to any conclusions.
– The most interesting thing I’ve read in the PoM volume is a Kripke-flavoured argument by Joseph Levine regarding qualia – in a nutshell (because the argument is fairly long), he argues that there is an ‘explanatory gap’ in a statement like (1) Pain is c-fibers firing that there isn’t in a statement like (2) heat is molecules in motion – (2) can be functionalized while (1) cannot. From this, he argues that the truth or falsity of (1) is inaccessible epistemically. Levine accepts that qualia are real (or at least accepts that the intuition we have that qualia are real is something we should follow), and since he doesn’t want to take the eliminativist line, he’s left with a bit of a head-scratcher. I’m going to go into more detail about the argument at a later time, so for now, this is all you get.