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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