A redated post.
This is a follow-up to my previous post, The Concept of Matter
I see a fundamental problem that is going to plague any materialist account of the mind. Materialists often piggy-back the case for materialism on the success of reductive analyses in science. But let's take one of the most successful scientific reductions, the reduction of heat in a gas to the mean kinetic energy of that gas. From one perspective, this reduction appears to explain heat away, in particular the element of heat that feels warm. By knowing that the air molecules are moving faster we can infer nothing about the fact that people are more likely to take their jackets off when that happens. They also feel warmer. But that, says science, is not an intrinsic feature of heat that is what happens to human minds in the face of heat. By siphoning off secondary qualities to the mind, the mechanistic reduction of heat is enabled. But when we get to the mind, we have no place to siphon of the "mental" properties.
Edward Feser writes:
One result of this is that materialists have, in the view of their critics, a tendency to give accounts of mental phenomena that leave out everything essential to them: qualia, consciousness, thought and intentionality get redefined in physicalistic terms, with the consequence that materialist analyses convey the impression that the materialist has changed the subject, and failed genuinely to explain the phenomenon the analysis was supposed to account for. This is arguably the deep source of the difficulties that have plagued materialist philosophies of mind. If the materialist conception of explanation entails always stripping away from the phenomenal to be accounted for anything that smacks of subjectivity, meaning, or mind-dependence, then a materialist “explanation” of the mind itself will naturally seem to strip away the very essence of the phenomena to be explained. Being, at bottom, attempts to explain the mental in terms that are intrinsically non-mental, such would-be explanations appear implicitly to deny the mental; that is to say, they end up being disguised forms of eliminative materialism. Some professedly non-eliminativist philosophers of mind come close to admitting this: Fodor, for instance, has famously written that “If aboutness (that is, intentionality) is real, it must really be something else.”
A Short Introduction to the Philosophy of Mind (Oxford; Oneworld, 2005) pp. 172-173,
This results in an interesting phenomenon; materialist philosophers attempt to give an account of some mental phenomenon. But either they implicitly bring in the very concepts they are trying to explain materialistically, or they give an account of the mental phenomenon in which the phenomenon to be explained isn’t recognizable. A good example would be Richard Carrier’s critique of my book where time after time he claims that intentionality can be explained in physicalistic terms while using one intentional concept after another to explain intentionality!