The specific problem I want to discuss concerns consciousness, the hard nut of the mind-body problem

The specific problem I want to discuss concerns consciousness, the hard nut of the mind-body problem. How is it possible for conscious states to depend upon brain states? How can technicolor phenomenology arise from soggy grey matter?...We know that brains are the de facto causal basis of consciousness, but we have, it seems, no understanding whatever of how this can be so. (Colin McGinn)

Conclusion of Lucasís paper:

If the proof of the falsity of mechanism is valid, it is of the greatest consequence for the whole of philosophy. Since the time of Newton, the bogey of mechanist determinism has obsessed philosophers. If we were to be scientific, it seemed that we must look on human beings as (127) determined automata, and not as autonomous moral agents; if we were to be moral, it seemed that we must deny science its due, set an arbitrary limit to its progress in understanding human neurophysiology, and take refuge in obscurantist mysticism. Not even Kant could resolve the tension between the two standpoints. But now, though many arguments against human freedom still remain, the argument from mechanism, perhaps the most compelling argument of them all, has lost its power. No longer on this count will it be incumbent on the natural philosopher to deny freedom in the name of science: no longer will the moralist feel the urge to abolish knowledge to make room for faith. We can even begin to see how there could be room for morality, without its being necessary to abolish or even to circumscribe the province of science.

Note that Lucas, in this paper, explicitly allows that if a machine were built that became so complicated as to be in principle unpredictable, then we are in a new ball game. His argument is directed against mechanism. Fairly clear that this would be allowed by everyone: at a certain level of

Possible to see some real progress made over the last twenty or thirty years. the first is general agreement, both among supporters and opponents of strong AI that a machine that could experience the world would need to be a very great deal more complicated than anything we have now. You need to pile on mechanisms until the result is unpredictable. Quote Hillis here. Growing sophistication on both sides of the argument.

Cf Hofstadter ó the level I think may not be the level at which I sum; and the Chalmers argument that we might, if we are formal systems, turn out to be unable to spot our own Goedel sentences.

Quote Pat Hayes.

The computationalist hypothesis is not that cognitive phenomena can be *described* computationally (which is not a very deep claim, though one denied by Penrose, for example) but that such a description is *theoretically explanatory*, in the sense that it accurately accounts for what the cognitive system is doing. In other words, that the cognitive system *is* (in part, or in some respects) a computer, and that the cognitive activity it displays is, in fact, computational activity.


You are thinking of a computer as running a simulation. But that is not the computationalist hypothesis: it is far more radical than the claim that the mind could be simulated on a computer. Rather, it is the claim that the mind actually consists of computational activity in a biological computer. Bear in mind that a computer is also a material system with nothing in it but its physical make-up; but part of this makeup is the physical encoding of symbols which influence the behaviour of the machine in ways that reflect the meanings of the symbols.

Human beings rule-bound: there is the Pat Churchland / Nick Humphrey folk-psychology view. Against this might be argued that we are mistaken about which decisions we are free to make, yet that we are free to make some. Part of the time difficult to see what they are arguing against. That brings us back to the secret policemanís brain scanner.

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