[Martin Taylor 951017 10:50]
Bruce Abbott (951016.1935 EST)
+Rick Marken (951016.1945)
+Irrelevant side effects are
+effects that are not controlled by the control system (though they may be of
+great interest to the observer of the control system).
What I see in behavior is evidence of control, not
irrelevant side-effects of control. As an example, consider the complex
courtship rituals of some birds. What is often observed is a complex series
of movements which are manifestations of the workings of a sophisticated
control system operating at at least the "control of sequence" level, and
probably higher.
In my view, both are correct. When you are looking with a focus on exactly
one control loop, applying the Test to seek out a single scalar controlled
perception, everything that affects anything other than the CEV is an
irrelevant side effect. All those actions, so interesting to an outside
observer because they are disturbances (or potentially so) to that observers
controlled perceptions, have nothing whatever to do with the control system
being studied.
But...when we look at the control loop itself, rather than just the CEV
that is the observer's surrogate for the controlled perception, we see more.
We see _mechanism_. We see how the feedback function is constructed. And
in this we see the operation of lower-level control loops whose reference
values are continually changing. We see how the organism goes about
maintaining control of the highest level perception in question. Those
behaviours (not "actions") are not side effects. They may vary, from
occasion to occasion, but then again, they may not. A bower bird doesn't
produce the same bower every time, but he does build a structure with
characteristics we seem to think are the same, and one might presume
those characteristics to be CEVs for controlled perceptions (I've no
idea whether anyone has done the Test to see if they are, but it would
be a reasonable thing to do, and the sort of thing ethologists like to do).
When one is talking about side effects of control, one is necessarily dealing
with those effects on the world that do not influence the CEV corresponding
to the controlled perception. The behaviours Bruce is usually talking about
DO seem to influence some controlled high-level perception, and are
components of the feedback function, rather than side effects. As such,
it seems to me that they are worthy of study.
Irrelevant side-effects? Baah!
My sediments prezackly!
Martin