The explanatory gap . Consciousness is a mystery. No one has ever given an account, even a highly speculative, hypothetical, and incomplete account of how a physical thing could have phenomenal states. Suppose that consciousness is identical to a property of the brain, say activity in the pyramidal cells of layer 5 of the cortex involving reverberatory circuits from cortical layer 6 to the thalamus and back to layers 4 and 6,as Crick and Koch have suggested for visual consciousness. .) (...) Still, that identity itself calls out for explanation! Proponents of an explanatory gap disagree about whether the gap is permanent. Some say that we are like the scientifically naive person who is told that matter = energy, but does not have the concepts required to make sense of the idea. If we can acquire these concepts, the gap is closable. Others say the gap is uncloseable because of our cognitive limitations. Still others say that the gap is a consequence of the fundamental nature of consciousness. (shrink)

In Mind in a Physical World (1998), Jaegwon Kim has recently extended his ongoing critique of `non-reductive materialist' positions in philosophy of mind by arguing that Nagel's model of reduction is the wrong paradigm in terms of which to contest the issue of psychophysical reduction, and that an altogether different model of scientific reduction – a functional model of reduction – is needed. In this paper I argue, first, that Kim's conception of the Nagelian model is substantially impoverished and potentially (...) misleading; second, that his own functional model is problematic in several respects; and, third, that the basic idea underlying his functional model can well be accommodated within a properly reinterpreted Nagelian model. I conclude with some reflections on the issue of psychophysical reduction. (shrink)

Chalmers’s anti-materialist argument runs as follows.

Qualia are phenomenal properties of sensations and perceptual states: they are whatever it is that gives such states their “felt,” qualitative character. (In speaking of sensations, I speak of course not of mental objects or mental contents, but of mental events—of sensings, not sensa.).

Locke put forward the theory of consciousness as "internal Sense" or "reflection"; Kant made it inner sense, by means of which the mind intuits itself or its inner state." 1 On that theory, consciousness is a perception-like second-order representing of our own psychological states..