Abstract

‘Mental processes are brain processes’ is not a logically necessary truth, but nevertheless certain logical conditions must be fulfilled if it is to be a candidate for the role of contingent truth. Not just anything can, conceivably, be contingently identical with anything else: a play cannot be identical with its copies, nor beauty with a beautiful object. The propagation of light may be electromagnetic radiation, but it cannot conceivably be the tri-section of a right-angle. In this paper I shall be concerned with the general question of whether there are any logical barriers to mind-body identification, and I shall approach this via the more particular question of whether the mental processes of persons can conceivably be identical with the physiological processes of brains. It is my contention that identity theorists, by concentrating their attentions upon what were once called the “lower” parts of the soul rather than upon “higher” parts which are more typical of human persons, have paved a logical way for themselves which is artificially straight.