On 19 Aug, 01:51, Brent Meeker <meeke...@dslextreme.com> wrote: > I think you are right that the MGA is at the crux. But I don't know whether > to regard it > as proving that computation need not be physically instantiated or as a > reductio against > the "yes doctor" hypothesis. Saying yes to the doctor seems very > straightforward when you > just think about the doctor replacing physical elements of your brain with > functionally > similar elements made of silicon or straw or whatever. But then I reflect > that I, with my > new head full of straw, must still interact with the world. So I have not > been reduced to > computation unless the part of the world I interact with is also replaced by > computational > elements (I think this problem is swept under the rug with the phrase "at the > appropriate > level of substitution"). So suppose the doctor also emulates all the world > that I will > ever interact with. Now it is not so clear that such an emulation is > computable, but > suppose it is. Now my consciousness is entirely emulation - but it is also > entirely in > another, emulated, world. In that world it is physically instantiated. So > it has not > been shown that the emulation can be uninstantiated mathematics.
Our last two posts crossed in the ether! Yes, I've wondered about the possible reductio element in yes doctor - like it's sometimes forgotten that Schrödinger's poor old tabby was originally proposed as a reductio against the Copenhagenists. But I'm not sure I agree that "computation need not be physically instantiated" is strong enough - MGA is more dismissive of PM than that (Bruno sometimes says that appeals to PM are 'spurious' with respect to CTM). I think that the strong entailment of MGA is CTM + PM = false, and that yes doctor is a promissory note against some future theory of substitution (with the caveat that it won't be complete). David > > Brent --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to email@example.com To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---