[ExI] Simulating the brain (was Question for the psych squad?)

Stuart LaForge avant at sollegro.com
Mon Jul 10 08:37:46 UTC 2017

Stathis Papaionnou wrote:
>The brain is not a Turing machine, but it can be modelled by a Turing
>machine if the physical Church-Turing thesis is true; that is, if there
>isn't anything in physics that isn't Turing emulable.

This assumes a discrete physics that is not yet proven to be the case. At
best matter/energy are discrete due to QM but QFT happens in
differentiable manifolds of fluctuating quantum fields spread throughout
smooth space-time. I don't see why calculus should work on physical
systems if space-time is discrete.

If infinities exist ontologically, then space-time is a continuum. In
which case classical computers would have difficulties with irrational
numbers. They will never understand what makes perfect circles perfect
regardless if perfect circles actually exist or not.

Classical computers might always have trouble with irrational behavior as
well which is a well-documented aspect of the human brain at least with
respect to bounded rationality and behavioral economics.

For example, an AI running on a classical computer would be unlikely to
buy a lottery ticket unless it was programmed specifically to do so
because the odds make it inherently irrational. Yet millions of people do
and a (very) few think it was the best decision they ever made.

Another feature of behavioral economics that an AI running on a classical
computer would be unlikely to exhibit would be inequity aversion which is
the technical term why humans will share money with each other in the
Dictator Game and also why they will refuse free money if they can deprive
someone else of a substantially larger bunch of free money in the
Ultimatum Game.

Now I am not glorifying irrational thinking but it is distinctly human and
a  simulation of a human would not be believable without it. Indeed if
George Bernard Shaw is correct, then we owe all technological progress to
the irrational man.

Of course this argument goes out the window once quantum computing comes
online. QCs won't have any problem with irrational behavior in numbers or
people because they would be utilizing the infinities of continuum.

Stuart LaForge

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