Computing machinery and mentality

I reconsider the status of computationalism (or, in a weak sense, functionalism): the claim that being a realization of some (as yet unspecified) class of abstract machine is both necessary and sufficient for having genuine, full-blooded, mentality. This doctrine is now quite widely (though by no means universally) seen as discredited. My position is that, though it is undoubtedly an unsatisfactory (perhaps even repugnant) thesis, the arguments against it are still rather weak. In particular, I critically reassess John Searle's infamous Chinese Room Argument and also some relevant aspects of Karl Popper's theory of the Open Universe. I conclude that the status of computationalism must still be regarded as undecided, and that it may still provide a satisfactory framework for research.