[From Bill Powers (951014.0720 MDT)]
Bruce Abbott (951013.1245 EST) --
Systems that behave the same way, from the standpoint of an external
observer, are not necessarily organized the same way inside. Structures
that appear anatomically the same do not necessarily accomplish their
functions in the same way. Control systems are organized to create
certain outcomes, but the fact that the same outcomes keep occurring
does not mean that the same actions were used each time to create them.
If a bird builds a nest and a mouse builds a nest, there is no reason to
conclude that birds and mice share a common nest-building ancestor.
Nests have several functions, and an adaptive control system
organization will find a way to accomplish those functions quite
independently of how any other system might have accomplished the same
functions. If it happens that two organisms use the same method to
accomplish the same function, the reason may be simply that there is no
other easily-found method that will accomplish that function. One can't
conclude that there is some specific structure inside the organisms that
makes them both use the same method and hence get the same result.
[Hans Blom, how about some help here? If two adaptive control systems
end up controlling the same variables by the same actions, does this
mean that the world-models in the two systems are the same?]
The problems I see in your arguments and explanations is that behind
them there seem to be large numbers of assumptions that are contrary to
these principles. Moreover, these contrary assumptions are widely shared
in your profession, to the point where they are taken for granted. The
difficulty I'm having is in raising doubts about these assumptions
without appearing to claim that they are false. By trying to cast doubt,
I am not trying to claim that I know your statements are wrong, but
trying to show that there is a level of investigation that is called for
to find out whether the assumptions are justifiable. If stimulating a
rat's amygdala results in a rat's showing visible behaviors which, if
they occurred in a human being, would be called fear, this is not an
indication that the rat is experiencing fear or that the effect of the
stimulation on the rat is the same as it is for the human being. It's
not an indication to the contrary, either. It's an open question, which
can be resolved only by further investigation. The rat's amygdala has
been evolving just as long as the human's, and by now could be
performing functions with no parallels in the human, and accomplishing
similar functions by quite different means. COULD be.
Where did I read this? Was it a recent post? Somebody quoted somebody to
the effect that if psychology keeps on reporting only positive instances
of tested hypotheses, it will eventually consist entirely of false
facts.
I guess we'll have to put aside some arguments if we're to make progress
in developing PTC applications to behavior. I can see the logic in your
answers to my questions and comments, but can't seem to get across the
framework from which my questions arise.
You sent me some data a few weeks ago. You're going to have to remind me
of where we were in that process and what these data were for. So much
has been going on since then that I've lost the thread, and need a jump-
start. Wait until you're my age and you'll see.
ยทยทยท
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Best,
Bill P.