Abstract

The most central metaphysical question about phenomenal consciousness is that of what constitutes phenomenal consciousness, whereas the most central epistemic question about consciousness is that of whether science can eventually provide an explanation of phenomenal consciousness. Many philosophers have argued that science doesn't have the means to answer the question of what consciousness is (the explanatory gap) but that consciousness nonetheless is fully determined by the physical facts underlying it (no metaphysical gap). Others have argued that the explanatory gap in the sciences entails a metaphysical gap. The explanatory gap exists, they say, because there are two fundamental properties in the world that do not reduce to one another: Phenomenal and physical. This position is also known as 'property dualism'. A famous argument, formulated and defended at great length by David Chalmers, uses conceptual tools to argue for a metaphysical gap. When we just look at what the notion of phenomenal consciousness implies, we will find that it doesn't rule out that there could be entities functionally and physically identical to us but without phenomenal consciousness. A couple of further argumentative steps can get us from here to the conclusion that laying down the physical facts of our world does not necessitate phenomenal consciousness. I argue that this argument is compelling but that accepting the conclusion doesn't have the implication that science cannot discover what consciousness is. I begin by outlining and assessing a number of different positions philosophers and scientists have recently defended regarding the link between neurological systems and consciousness, I then argue that even if property dualism is true, that doesn't necessarily prevent the sciences from discovering what constitutes consciousness. That is, there may be no explanatory gap even if there is a metaphysical gap.