[From Bruce Abbott (960201.1820 EST)]

Bruce Abbott (960201.1020 EST) --

    Has the spark gone out of your romance?

Not tonight, Bruce, I have a headache.

Not again! Damned disappointing . . .

How about a comment on your use of control, influence, and determine as
if they had equivalent meanings?

I had some thoughts about that while writing my retrofaction (now
spontefaction) tutorial. Control as used in EAB is one of those words that
admits of degrees -- on can talk of stimulus control as being strong, weak,
or even absent under given conditions. Because the stimulus is not viewed
as _causing_ a given response, but only as affecting its liklihood of
emission, it would not generally be proper to say that the SD _determines_
the response; it is only an influence. However, the term "control" could
also be used when the state of one variable _determines_ the state of
another. This is the sense in which it is sometimes used by engineers, who
might speak, for example, of a "motor controller" that "controls" the
rotational speed of a motor, even though what is being referred to is an
open-loop system in which the setting of the controller determines the
amount of current flowing through the motor's windings. I used the term
"control" in both senses when describing the spontefaction system.

I noted that the disturbance would control (determine) the spontefacted
variable in the absence of spontefaction. In the presence of spontefaction
the influence of (control by) the disturbance diminishes so that it is 1/(1
+ G) proportion of the unspontefacted amount, where G is the loop gain of
the system. In EAB terms I guess we would say that control over the
spontefacted variable would weaken as G increased. On the other hand,
control over action by e would be strong, since in the example system a is
completely determined by e once the output gain has been fixed.

But this got me to thinking about how "strong" and "weak" control would be
defined. One sense of it is that Variable A has strong control over
Variable B if Variable A represents the major source of variation in
Variable B. But another sense appeals to how much A has to vary (in
proportion to its normal range of variation) to produce a given amount of
variation in B (in proportion to its normal range). This second definition
is closer to the idea of "sensitivity." Both ideas seem to be tied up
together in the idea of "strength" of control, in the EAB sense of the word.
I wonder what a good metric for this would be.

By the way, the disturbance would appear to exert excellent control over
system output so long as the reference signal remained constant, while
exerting very weak (perhaps even undetected) control over the sfv.



[From Rick Marken (960305.0815)]

Hans Blom (960305b)--

Control, as we talk about it, is a rather high-level concept that,
somehow, originates from the interaction of the more basic laws of
physics. At the level of the atom or molecule we don't see it yet,
at the level of the organism we do. We seem to need some complex
arrangement of units before control arises.

You seem to have discovered that control is a real phenomenon, that it is
exhibited by organisms and not atoms or (most) molecules. Perhaps now you
can answer the rather basic question about control that you avoided in the

Does the environment control behavior?

Good luck.


Bill: "Living control systems, and most nonliving ones, control their
sensory inputs, not their motor outputs.

"Behavior of a living control system is the control of perception, not

Gavin: "You would not believe how hard to is to convince anyone of these two

(Assumed premise, here: "Live human beings, including you and I, are living
control systems.")

Words have a bad habit of having more than one meaning. When two meanings
collide in the same context, trouble ensues.

Suppose a neighbor is giving you a ride. You say, "What are you
controlling?" He says, "Why, I'm controlling my car, of course -- its speed,
its direction, and so forth."

If you say, "No, no. You aren't controlling your car, you are controlling
your perceptions -- of the position of the yellow line, of the pressure you
are exerting on the accelerator, etc.", he will shut down.

Would it help if you say, instead, "Yes, and you are controlling your car by
controlling your perceptions -- (etc.). That's how you constantly change
your car's movements as you go down the road. This idea is called Perception
Control Theory."?

And then, of course, you go on to your best explanation of PCT. Once you've
got him hooked, he might even end up agreeing that, in fact, one can't
control anything except by controlling one's perceptions.


[From Bill Powers (2011.10.27.1210 MDT)]

Suppose a neighbor is giving you a ride. You say, "What are you
controlling?" He says, "Why, I'm controlling my car, of course -- its speed,
its direction, and so forth."

If you say, "No, no. You aren't controlling your car, you are controlling
your perceptions -- of the position of the yellow line, of the pressure you
are exerting on the accelerator, etc.", he will shut down.

Yes, and that's why I wouldn't use that approach. I would ask, "How do you know you're controlling the speed?" He might say "Because it's stayin the same uphill and downhill." I would ask "How do you know it's staying the same?" Answer, perhaps, "I can see the speedometer reading and it's not changing." I'd ask, "Is that what you watch when you want to control the speed accurately?" And so on. Eventually, I'd lead the person to saying that he can perceive the speedometer reading, and that if he couldn't, he couldn't control the speed so well, and if he couldn't perceive the world moving past outside the car, either, he probably couldn't control the car's speed at all. In fact, if the speedometer was reading high (more questions), the car's actual speed would be controlled at a level lower than the indicated speed. Eventually the conclusion: you can control ONLY what you perceive.

As you imply, just contradicting what a person says is not helpful.


Bill P.


At 09:57 AM 10/27/2011 -0600, Ted Cloak wrote:

From [Marc Abrams (2004.11.29.0826)

I just ran across some old research that shows why it is so extremely important to ‘sell’ PCT and get folks out there interested in the controlled input model, better known as PCT, if in fact that is what PCT is.

One of Bill’s favorite authors Karl Pribram among others have done some research into protocritic processes and what they have found is amazing.

Among other things they have found various regulatory ‘control’ processes that are interesting. For instance; salt concentrations in our blood affect how thirsty we feel, and the level of sugar affects how hungry we feel. S why is this so important?

Well, I’m glad you asked. :slight_smile:

It just so happens that with diabetics, the ability of the cells to utilize insulin is well known. This causes the cells to report a lack of glucose available even though this is not the case. There is plenty available, the cells just can’t ‘see’ it.

Because of this, diabetics would in fact feel much hungrier on average, eat more, be heavier, etc., etc., even though there is no ‘reason’ to be so.

So even in measuring your blood sugar levels and keeping your sugar ‘under control,’ the control system responds with hunger pangs reagardless.

I believe this might be ‘conflict’ between control systems.

Of course at this time no one knows how this happens or what the exact mechanisms are that are involved. But it is clear, at least to me, that this must be investigated from a PCT perspective.

An intriguing question surfaces. Does obesity ‘cause’ diabetes or does diabetes ‘cause’ obesity?