Bruno, when you talk about the doctor offering one a replacement brain you usually describe the substitute as digital, although I think you have sometimes just said that it is artificial. My recent remarks about "game physics" got me thinking about this distinction, if indeed there is one.
Suppose Dick's friend Harry, having been previously diagnosed with an incurable brain cancer, has had an artificial brain installed. The doctor tells Dick that he has replaced Harry's brain with a (very sophisticated!) battery-driven clockwork substitute. Harry tells Dick that the replacement has been entirely successful: "After the operation I felt a little woozy at first, but I feel great now. My memory is excellent - if anything better than before - and my appreciation of the finer things in life is as vivid as ever." Dick is a bit sceptical at first (his faith in clockwork has been prejudiced by a rather unreliable fake Rolex he bought in Hong Kong) but over a period of several months of careful observation he finds he can't distinguish any difference whatsoever between Harry's new clockwork personality and his former self. Their friendship is undiminished. This turns out to be just as well, because - horror of horrors - Dick is shortly afterwards also diagnosed with a terminal brain condition. Should he now be willing to submit to the same procedure as Harry? He is still a little sceptical of clockwork, but the evidence of Harry's successful transformation is very difficult to discount, and the doctor shows him several other "before and after" videos with equally convincing outcomes. The artificial brains may be clockwork, but the doctor assures him it is clockwork of unprecedented sophistication and precision, unheard of even in the hallowed halls of Swiss horology. Dick has stumbled across the Everything List, and is rather persuaded by the computational theory of mind. Trouble is, the doctor is not of this persuasion. He tells Dick that the goal of the operation is only to substitute a clockwork analogue for the electro-chemical mechanisms of his organic brain, and that on this basis Dick can confidently expect that the same inputs will reliably elicit the same responses as before. Hearing this, Dick is now worried that, however successful the replacement of Harry's brain has been behaviourally, his friend is now essentially a mindless clockwork mechanism. Since he certainly doesn't want to suffer such an indignity, should he say no to the doctor? The question that troubles Dick is whether, assuming comp, he should accept a genuinely behaviourally-indistinguishable body, irrespective of its brain being organic or clockwork, as an equivalent "avatar" according to the rules of the comp game-physics. If so, Dick should have no reason not to accept a behaviourally-indistinguishable, clockwork-equipped body as enabling his continued manifestation relative to the familiar environments to which he has become so emotionally attached. Time is short, and he must act. What should he do? David -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.

