D. Gene Witmer

Charles Siewert has given us an ingenious thought experiment involving a limited lack of conscious experience. The possibility of the described case is incompatible with a number of popular theories of consciousness. Siewert acknowledges, however, that this possibility is not a direct threat to "hidden feature" theories. I aim to do two things: first, strengthen his defense of the claim that the case is genuinely possible by considering and rejecting some further attempts to explain away our temptation to believe it possible; and second, to explore how a hidden feature approach could be developed and made plausible

The manifestability argument presented by Papineau and Loewer turns on the premise that nonphysical properties are capable of making a difference to physical conditions. From this and the completeness of physics a strenuous supervenience conclusion is supposed to follow. I argue that the plausible version of this premise implies a weaker supervenience thesis only, one that is too weak to be of any use for a physicalist. There is a more contentious premise one might use to deduce the needed conclusion, but that more contentious premise has no empirical support

Physicalists motivate their position by posing a problem for the opposition: given the causal completeness of physics and the impact of the mental (or, more broadly, the seemingly nonphysical) on the physical, antiphysicalism implies that causal overdetermination is rampant. This argument is, however, equivocal in its use of 'physical'. As Scott Sturgeon has recently argued, if 'physical' means that which is the object of physical theory, completeness is plausible, but the further claim that the mental has a causal impact on the physical is no longer so evident. In this paper I assess the damage due to the ambiguity of 'physical' and provide a repair to the overdetermination strategy.