X-Message-Number: 11626
From: Thomas Donaldson <>
Subject: More for Mike Perry: simulated persons and real persons
Date: Tue, 27 Apr 1999 23:53:56 +1000 (EST)

More for Mike Perry:

The important point behind what I was saying in my previous message (why
Turing machines, or indeed any sequential computer, are quite inadequate
as machines able to act in the world just as well as persons can) is that
persons are much more than computational devices.

Not only are persons more than computational devices, but if you try to
see them ONLY in terms of computation you will very likely miss the 
construction of a real person by light years. At the lowest, brute level,
acting in the world involves such things as being able to name and 
manipulate real objects --- which necessarily fail to resemble any
ideal object at all closely. Not only that, but even to use real language
(I claim) will ultimately require much more than just the ability to
compute things (I will allude here to the major point I made a few
weeks ago: primarily, we deal with the world, not with language, and
it is very unlikely that any device can be built able to use English
--- or any other human language --- as well as humans if that device
consists only of a computer, a keyboard, and a video screen(*)).

You cannot simply assume such an ability, as I said before. If you believe
such a machine is possible, you must prove it... and by so doing prove,
as I said before, that given the vocabulary and grammar of English then
no other mapping of English onto reality is possible other than the one
we learned by learning to name things in the world. We did not learn
the definitions of elementary words in terms of other words, we learned
them by seeing how the world behaved and acting in that world.

And it is this relation to reality which makes Turing machines, as
means to analyze how humans think, so ludicrously inadequate. For such
purposes as we use our brains, it is essential and not at all just a side
issue that we are so highly parallel. Simply to learn to talk (and hear)
we use that parallelism; when I said that much more is needed than just
a computer to make a person (artificial or not) I was not referring to 
drives such as hunger or thirst. Yes, we would need such drives too, but
the FUNDAMENTAL problem shows up even for a machine able to think about
the real world and plan actions to be done in it (rapidly enough that
they might really be done, of course).

I know that various people will point out how fast computers have become
in doing various calculations etc etc. Yes, and WE HUMAN BEINGS built them
to be so fast on tasks for which our own evolution has not caused us to be
fast (except in terms of vision and graphics, which is known to require
very great --- but also highly specialized --- computer power). That point
emphasizes just how parallel we really are, while at the same time
pointing out that for evolutionary reasons we simply did not evolve the
ability to do the calculations needed to design a jet plane or understand
chemical reactions at similar speeds. That is why we built computers to 
help us do those things --- while no one yet has needed a computer to 
allow them to look at the world.  

And yes, we may build artificial systems to allow those to see who are not
only blind because they lack eyes, but blind because they lack the brain
areas involved in our visual cortex. Those systems may be built on
biological principles using biological methods, or by some other method.
Not only that, but our past evolution says nothing about our future needs:
if someone really needs in their brain (rather than in handy computing
devices which can be changed for others at will, just as with other tools)
an ability to design wings for jet planes, then that ability can be 
produced as part of them too (**). Again, by biological or by other
methods. There isn't even any BIOLOGICAL reason why our neurons could not
be redesigned to work faster --- they work as fast as they do, again,
because our evolutionary history has not required them to work faster.

In short, if you adopt Turing machines as models for how our brain works,
you miss the entire point of what constitutes a person rather than a
computer. And the very most you could produce would be a simulated 
person (NOT aware) in a simulated world --- and hardly a very well 
simulated person, either. As for awareness, they will be no more aware
than simulated rainfall can make anyone wet. 

			Best and long long life to all,

				Thomas Donaldson

(*) as is the normal setup for the Turing test.
(**) there are enough such abilities that separating them from us as 
     tools seems to me much the most efficient means

Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=11626