On 9 May 2015 at 11:24, meekerdb <[email protected]> wrote: > On 5/8/2015 2:58 PM, LizR wrote: > > On 9 May 2015 at 09:02, meekerdb <[email protected]> wrote: > >> On 5/8/2015 1:33 AM, LizR wrote: >> >> On 8 May 2015 at 18:37, meekerdb <[email protected]> wrote: >> >>> On 07 May 2015, at 14:45, Bruce Kellett wrote: >>> >>>> >>>> We can use an original biological brain, or an equivalent digital >>>>> replacement -- it does not make any significant difference to the >>>>> argument. >>>>> The first point is that in some conscious experience, be it a dream or >>>>> anything else, there might be a portion of the 'brain' (in quotes because >>>>> it can be biological or digital) that is not activated, so this can be >>>>> removed without affecting the conscious experience. >>>>> >>>> >>> This idea of removing unused parts of brain so only "active" elements >>> remain, seems problematic to me and not just because of counterfactual >>> correctness. The ability to do this is implicit in the assumption that the >>> physics of the brain is classical. >> >> >> But comp is based on the assumption that consciousness is the result of >> classical computation. If that assumption's wrong then comp fails, of >> course, from step 0 - no need to worry about the MGA. >> >> Bruno points out that a classical computer can compute anything that a >> quantum computer can so it doesn't exactly fail; what I think it implies >> that the classical computation must include the "environemnt", i.e. all the >> extra physical degrees of freedom and entanglement that make the brain >> computation (approximately) classical. >> > > That sounds like putting the cart before the horse. The question is, can > the brain and environment be extracted from the assumption that > consciousness is classical computation? Which is, of course, still an open > question. > > True, it's a problem from either end. If you just assume computation is > fundamental then you have to get QM out of it and ALSO the approximate > classicality of the physically realized computation. >
Exactly. That is Bruno's problem. > Plus, assuming no quantum entanglement with the environment is involved > in consciousness (as seems likely given the decoherence times of neurons > etc) > > That's not taking the QM seriously. QM says that it's the decoherence > due to entanglement with the environment that produces the classical > behavior. > OK, I think even with a little brain I'm beginning to see the point here. I'm not yet sure if it's relevant, however. I think Max Tegmark's point was that the environment of a neuron is other neurons (and the surrounding material - glia, blood, etc) and that everything in a brain is decohering far faster than than the timescales of consciousness. Why would taking the QM seriously prevent the brain behaving as a classical computer on those timescales? Or to move the question into a (perhaps) better known realm, why would it stop a computer running an AI programme behaving as a classical computer? If the brain is fundamentally different to an AI due to quantum effects, that invalidates comp at step 0 (and possibly invalidates strong AI as well). -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
