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cory doctorow
But it’s a cheat. Evolutionary algorithms depend on the same
mechanisms as real-world evolution: heritable variation of candi-
dates and a system that culls the least-suitable candidates. This
latter — the fitness-factor that determines which individuals in a
cohort breed and which vanish — is the key to a successful evolu-
tionary system. Without it, there’s no pressure for the system to
achieve the desired goal: merely mutation and more mutation.
But how can a machine evaluate which of a trillion models of
a human brain is “most like” a conscious mind? Or better still:
Which one is most like the individual whose brain is being mod-
eled?
“It is a sleight of hand in
Spiritual Machines,”
Kurzweil admits.
“But in
The Singularity Is Near,
I have an in-depth discussion about
what we know about the brain and how to model it. Our tools for
understanding the brain are subject to the Law of Accelerating
Returns, and we’ve made more progress in reverse-engineering
the human brain than most people realize.” This is a tasty Kurz-
weilism that observes that improvements in technology yield
tools for improving technology, round and round, so that the
thing that progress begets more than anything is more and yet
faster progress.
“Scanning resolution of human tissue — both spatial and tem-
poral — is doubling every year, and so is our knowledge of the
workings of the brain. The brain is not one big neural net, the
brain is several hundred different regions, and we can understand
each region, we can model the regions with mathematics, most of
which have some nexus with chaos and self-organizing systems.
This has already been done for a couple dozen regions out of the
several hundred.
“We have a good model of a dozen or so regions of the auditory
and visual cortex, how we strip images down to very low-resolu-
tion movies based on pattern recognition. Interestingly, we don’t
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