Ahistorical homology and multiple realizability

Abstract

The Mind-Brain Identity Theory lived a short life as a respectable philosophical position in the late 1950s, until Hilary Putnam developed his famous argument on the multiple realizability of mental states. The argument was, and still is, taken as the definitive demonstration of the falsity of Identity Theory and the foundation on which contemporary functionalist computational cognitive science was to be grounded. In this paper, in the wake of some contemporary philosophers, we reopen the case for Identity Theory and offer a solution to the problem of multiple realizabilty. The solution is based on the necessity, at the time of establishing identity relations, of appealing to the notions of “homology” and “analogy” developed in the nineteenth century by Richard Owen. We also suggest that these notions are useful in order to correct certain shortcomings of some recent attempts at rebutting the Multiple Realizability argument.