This paper suggests a critique of the zombie argument that bypasses the need to decide on the truth of its main premises, and specifically, avoids the need to enter the battlefield of whether conceivability entails metaphysical possibility. It is argued that if we accept, as the zombie argument’s supporters would urge us, the assumption that an ideal reasoner can conceive of a complete physical description of the world without conceiving of qualia, the general principle that conceivability entails metaphysical possibility, and (...) the general principle that for any s and t the metaphysical possibility of s & − t entails that s does not necessitate t, we have to conclude not that materialism is false but rather that either materialism or the “mental paint” (or “phenomenist”) conception of phenomenality is false. And further, given the initial advantages of materialism, the fact that proponents of the zombie argument are not allowed to rely on arguments against materialism in confronting this dilemma, and difficulties with arguments in favor of phenomenism, we find ourselves pushed to reject the mental paint conception rather than materialism. Or at any rate, it is hard to see how the proponent of the zombie argument can carry the burden of proof that lies with her. Thus, whether or not those premises of the zombie argument are true, the argument fails to refute materialism. (shrink)

Benjamin Libet compared the perceived time of direct brain stimulation to the perceived time of skin stimulation. His results are among the most controversial experiments at the interface between psychology and philosophy. The new element that I bring to this discussion is a reanalysis of Libet's raw data. Libet's original data were difficult to interpret because of the manner in which they were presented in tables. Plotting the data as psychometric functions shows that the observers have great uncertainty about the (...) relative timing of events, as seen the shallow psychometric slopes. A second indication of uncertainty comes from Libet's use of three response categories, A first; B first; and A and B simultaneous. The large number of “perceptually simultaneous” responses provides a further measure of the difficulty of the judgment. There are thus a very broad range of stimulus delays in which the subject is unable to make an accurate ordering response. These points provide evidence that there is no compelling reason to invent exotic or ad hoc mechanisms to account for Libet's data since the uncertainty window is large enough to allow simple mechanism such as memory shifts. Libet argued that his data provide evidence for a backward referral in time. I argue that even though Libet's own data are weak, there are good arguments for a backward referral mechanism to help the subject make sense out of the tangled chaos of asynchronous information associated with experienced events. (shrink)