How to solve the mind--body problem

The identity of conscious states and brain states must remain a mystery until we find a way of characterising both sides of the equation in terms that have the same ‘dimensions’. In this paper I stress the need for ‘dual currency concepts’ that not only are but can be seen to be as appropriate for talking about, say, the experience of pain as for talking about the corresponding working of the brain. In the light of evolutionary theory I make a radically new proposal for what the common dimension is, centred on the idea of ‘authorship’.