Imitation vs Modelling

[From Rick Marken (920812)]

Oded Maler (920811) says:

But for engineers (unlike reverse-engineers) this
problem does not exist, because they build the boxes, they know the
I-O ("S-R") characteristics of (some of) the components they put in
the loop, and all your protests against S-R, which might be valid in
the context of psychological experiments, seem like fighting
non-existent windmills. They don't know and don't care about ID-IV
tests and the only arguments you may have with them is whether it is
useful or not to use the language of hierarchical servo loops,
reference signals etc. in order to achieve interesting performance (I
refrain from using the word "behavior"..).

The argument I have with roboticists is the same as my argument with
psychologists (both groups, incidentally, believe that I am "fighting
non-existent windmills"). Both groups are trying to find a way to imitate
behavioral appearances rather than model the underlying processes that cause
those appearances. It all comes down to understanding the difference between
behaving (what we see people -- or artifacts -- "doing") and controlling
(what we can't see people -- or artifacts -- doing, viz. keeping perceptual
variables at reference levels using whatever means is demanded by the
situation). This is much more than a matter of getting people to "use the
language" of PCT. It is a matter of understanding what it means to control.
I agree that roboticists often use control systems in their efforts to build
machines that put on "interesting performances". What I object to is the
orientation towards the performance -- rather than the cause of the
performance; the control of perception (at least in living systems). The
difference to me is between imitation (the current goal of psychological
theorists and roboticists) and modelling (finding the underlying organization
that produces the appearance). When you successfully do the latter, the
behavior of your system will also imitate that of the real system -- but it
will do it for the right underlying reasons (and, thus, will imitate the
behavior in new situations in which the "imitation only" device will fail).

But I don't really care whether the roboticists ever understand the difference
between imitation and modeling; their goals (as I understand them ) are simply
not interesting to me. I don't need an artifact running around my house
bringing me the paper or mopping up the floor. Robotics is interesting
to me only as an implementation of a model of real living systems;robots are
of value to me only insofar as they further my understanding of human nature.
Whether a roboticist succeeds in making his or her toy behave in some
interesting way is of no particular interest to me; whether they do it by just
imitating behavior or if they do it by developing a model that accidentally
includes some of the principles of control, I don't care. I'm not interested
in seeing cute behavior (unless I'm at Disneyland). I care about the
underlying principles -- not the superficial appearances -- and I see no
evidence that roboticists understand the principles of organization of
living systems any better than do psychologists.

While I could care less what roboticists do (except insofar as their creations
can serve as existence theorms for a paricular model of behavioral organiza-
tion), I do care what psychologists do and think because they are
presenting a model to the world of "how people work" and people assume that
these folks know what they are talking about. The fact that psychology
is currently based on the wrong model is not just unfortunate
in terms of the progress of our understanding of human nature; it is
also unfortunate because wrong models of people lead to wrong ways of
dealing with people in the the real world. And this produces REAL life
problems for all of us. People typically deal with other people in cause-
effect terms (as sr devices or output generators). This leads to a focus on
overt behavior (the kind that roboticists want to imitate) and efforts
to get that behavior to look the way it "should" look. So rather than
focusing on what people are trying to control -- and helping them control
it so that the means they select are not so disturbing to others --
people tend to try to solve problems manipulatively -- with the attendant
social disasters. These social disasters are just not necessary at all.
I want a better world for my children and it won't happen unless people
start to understand that their basic assumptions about how people work are
FALSE. Force won't work; inflexible system concepts won't work, repression
won't work; CONTROL WON'T WORK (in the long run) precisely because people
ARE controllers. That's the message I care about; and it's why
I think an understanding of PCT is so important. If the roboticists already
do understand the the principles of control (as you imply) and are just using
different language, and if they understand that these principles apply
to people as well as robots, then they would be most helpful allies in
our efforts to help psychologists (and lay people) understand the nature
of human nature.

Best regards

Rick

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Richard S. Marken USMail: 10459 Holman Ave
The Aerospace Corporation Los Angeles, CA 90024
E-mail: marken@aero.org
(310) 336-6214 (day)
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