[from Bruce Nevin (980219.1333)]
"Behavior is the control of perception" has an in-your-face quality, catchy
title for a book.
In general discourse it would probably be clearer to say something like
"when an organism behaves it is controlling perceptions." There are several
reasons that I can think of.
"Behavior" is an abstract noun derived from a verb "behave". When we use a
noun, we get fooled into thinking there is something there to which it
refers. Not so for an abstract noun. "Behavior" correlates with an infinite
variability of means for internally specified ends. There's no isolable
"there" there. That's why the underlying verb or the more verblike
"behaving" is clearer.
Behaving can be attempted control if disturbances overwhelm the organism's
ability (or willingness) to control. Saying "behavior is the control of
perception" obscures this. More generally the abstract noun "behavior"
obscures the role of disturbances in the control loop.
Generalizing that, the abstract noun encourages us to think of behavioral
outputs in isolation from the control loop in which they occur. When we
mean "behavior" in that sense, we would be better off saying "behavioral
outputs" as distinct from "behaving."
A core insight of PCT is the simultaneity of the dissected aspects of the
control loop -- proximal stimulus s, perceptual signal p and reference
signal r input to a comparator, error output e, behavioral outputs o,
perceptible effects of o through the environment on s -- the startling,
synergic character of circular causation such that (during effective
control) a change anywhere both causes and is caused by a change everywhere
in the loop. That is why actually delving into a model is so important.
Think about Bill's experience quitting smoking. There was the intellectual
understanding of the tricky logic, the recognition that it was true. Then
there was reorganization and a change in the way of controlling
perceptions. He likened this epiphany to "getting" PCT:
Bill Powers (980217.0619MST)--
It's sort of like grasping PCT for the
first time -- everything in you yells that it can't be that simple. If it's
that simple, how come I didn't understand it long ago?[...] Something in me still drops its jaw
at that. But it's starting to seem real.
I think maybe what Rick is controlling for is the sound of our jaws
dropping. That's maybe why it's so hard to convince him that you've "got"
it. But some people function in a more compartmentalized way than others,
and the work of reorganization takes time as one or another compartment
gets confronted with the facts of life. Such people can hold mutually
inconsistent views, and hold each view quite rigidly, by preventing
communication between them. This way they can be open minded but rigid. It
may be a way of reducing the discomforts of reorganization. They are
unlikely to have a "thunderclap" conversion experience.
Tracy Harms (980219.10)--
It must be a false claim, that the output of a control system is a
function of perceptual error.
You are right, it's false if taken in isolation. That is, it's incomplete.
As Bill said (980219.0359 MST)
[...] at the same time, the error signal is a function of the behavioral
output. The error signal is not an independent variable. The loop is
closed. You can't specify the error signal without knowing the current
value of the reference signal, the behavioral output, and the disturbance.When you start trying to describe behavior as if the components in the loop
become active one at a time, you start departing from the PCT picture of
behavior, and you move back toward the old cause-effect sequential view.
The control loop is closed and active even when there are no disturbances;
a disturbance merely results in a shift in the equilibrium state of the
whole loop, maintaining the controlled variable as close to the reference
condition as possible given the system parameters.
And as Rick said(980218.2050):
While it is true that o = f(e) it is also (and simultaneously)
true that e = g(o). [...] try the "Nature
of Behavior" demo at my web site. You will see that there is no
observed cause-effect relationship (no correlation) between
perception [...] and output, even though we know that such a
causal relationship (o = f(r-p)) is part of the closed control
loop.If one wants to say that a control system "responds to error"
one should also add (immediately) "while the error is responding
to the response to error". But I think it is much easier (and
clearer, becauase it calls attention to what is most important
about the control loop (the fact that it keeps some perception
at a reference level) to say that a control system "controls
a perception".
Bruce Nevin