Eugen Leitl writes:
> > likely that multiple error correction and negative feedback systems are
>in
> > place to ensure that small changes are not chaotically amplified to
>cause
> > gross mental changes after a few seconds, and all these systems would
>have
> > to be simulated as well. The end result may be that none of the cellular
>
>Of course. And your point is?
>
> > machinery can be safely ignored in an emulation, which is very far from
> > modelling the brain as a neural net. I may be wrong, and it may be
>simpler
>
>Strawman, again.
>
> > than I suggest, but as a general rule, if there were a simpler and more
> > economical way to do things, evolution would have found it.
>
>Biological tissues are not evolved to e.g. work with EM radio, or electron
>spin for
>information processing, or nuclear fission for power sources, or an enzyme
>to
>deposit diamond. Regardless how many gigayears you spend evolving, this
>will
>never be discovered due to kinetic blocks, fitness crevices, and sterile
>areas
>in fitness space which can't be crossed incrementally. Human design doesn't
>have that limitation. We can in principle do whatever evolution can do (by
>explicitly invoking the process, in an accelerated model), and more.
>
>The fitness function of discrete information processing in solid state is
>entirely different from CNS. Most of what the genome does is not devoted to
>neural information processing, and, frankly anisotropically excitable
>nonlinear medium is a control paradigm from hell.
>
>There are simpler and more economical ways to do things, and we'll be there
>in about 20-30 years. Meanwhile, biology reigns supreme in crunch/Joule,
>integration density, error tolerance and a few other things, but we're
>gaining on it rapidly.
There is a fundamental difference between copying evolution's version of,
say, a pump, and a brain. The whole complex business of excitable cardiac
muscle cells beating in synchrony with a pacemaker need not be emulated, of
course, if you are just trying to build an efficient artificial heart. If
the purpose is just to pump, what may have been necessary for nature is
superfluous for an engineer. On the other hand, with a brain, all the
elaborate detail is intrinsically important: the engineer doesn't just want
to build an efficient processor which will keep the human body going, but to
copy the *actual* processor, however needlessly complex.
But perhaps I should end this thread by admitting that I was not aware that
there were "mind uploaders" out there seriously contemplating the emulation
of a brain down to the molecular level, and express my astonishment, which
hopefully will turn into admiration, at your 20-30 year time span for
completing such a project.
--Stathis Papaioannou
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Received on Mon Jul 11 2005 - 09:19:34 PDT