Choosing and Controlling (was [mol] another article on the In Control blog)

[From Rick Marken (2016.09.24.1000)]

RM: I mistakenly posted something to CSGNet that was meant for another list. Bruce replied to it so I"ll reply to Bruce here, but under a new subject head to keep it separate form the thread in teh other list.


Bruce Abbott (2016.09.22.1840 EDT)–


BA: I’m not sure I agree entirely with Rick’s position as expressed in the repost below (no surprise to Rick, I’m sure).Â

RM: You are so right.Â


BA: I’ll explain below.


RM: What I mean by “automated” is that the outputs that bring a system’s perception to the reference are a deterministic function of error. Those outputs are references for lower level systems when the system involved is a higher level system. So when control is working correctly there is no “choosing” what to do. This is true even when the perception being controlled is a program perception with “choice points”. When you know how to control a program perception, such as a recipe, skillfully, you make the “choices” at the choice points automatically.Â


RM: From a PCT perspective the only time you are having to choose is when you are in conflict.Â


BA: This was Bill Powers’ position as well, and I understand the logic of it. But there are many situations in which one or more options become available, only one of which can be selected at the time.Â

RM: Could you give me a concrete example of such a situation?


BA: However, there may be background conditions that make one choice better under THESE conditions, and another choice better under a different set of conditions. Having encountered these cases many times, one may have developed a habit of selecting one or the other, depending on existing conditions.Â

RM: Again, a concrete example would help. Also, how do you see “choice” and “habit” fitting in to a PCT explanation of that situation.Â


BA: The choice becomes automatic but different selections are made at different occasions.Â

RM: This sounds like hierarchical control to me. The choice is an output driven by error; the different occasions are disturbances to a higher level perception that results in error driven changes in the “choices” made by this system, resulting in a change of the reference sent to the lower level system, changing the error in this system, thus changing the “choices” made by the lower level system. But maybe you have something else in mind that can’t be handled by a hierarchical control organization?

BA: Selections are made without conflict being involved, on the basis of perceptual cues that indicate which conditions are currently in force.

 RM: Perceptual cues are not part of PCT. What you call a “perceptual cue” would probably be a disturbance to a controlled variable in PCT For example, a conditioned stimulus (CS) in classical conditioning is not a “cue” to the occurrence of the unconditioned stimulus (UCS). The PCT explanation of the apparent “cueing” effect of the CS is that the CS becomes (through reorganization) part of a higher level controlled perceptual variable so that, when the CS is present it is a disturbance to that variable that is corrected by producing the UCR (now called the CR).Â


BA: It seems to me, then, that the statement that choice always involves conflict depends on the definition of “choice.â€? If choice is a branch-point in a program-level control system (offering two or more options that will be selected from depending on the state of some variable, then choice is present whether or not conflict is involved.Â

RM: Yes, I try to distinguish “choosing” from “having options”. I think of “choice” as selecting or deciding between options. In order to be able to control, a control system needs options – the “degrees of freedom” of output needed to be able to bring a perception to a reference state and keep it there, protected from disturbances. But a control system doesn’t really choose which option to select at any particular instant; the option selected is determined by the error signal. This is true even in the control of a program, where the option “selected” at each choice point is determined by the “state of some variable” at that point; the state of this variable determines the value of the error signal and, thus, which option is selected.Â

RM: The only time something like choice, in the sense of deciding between options, is involved in controlling, as far as I can tell, is when there is a conflict between control systems. In this case, the options selected by the control systems involved in the conflict are determined by error, but from a higher level point of view, since neither control system is “getting what it wants”, it can feel like one is in a position of having to choose whether one “really wants” the perception controlled for by one system or by the other.Â


BA: (This is true even if the choice is made at random.)Â However, if choice refers only to the case in which conflict arises between control systems, and one has to select a course of action in order to resolve the conflict and thus reestablish good control, then choice is by definition only present then and the branch-point case will have to go by some other name (e.g., selection).

 RM: Yes, as I said above I don’t consider the existence of options as being a choice situation.Â


BA: It also seems to me that minor conflicts arise all the time that do not threaten good control. Having to choose between cake and ice cream for dessert does not materially upset my ability to control for having dessert, although choosing may impose a small penalty in terms of delaying consumption.

RM: Yes, I agree. These little conflicts come up all the time – they are real choice situations, from my perspective – and they are readily solved by reorganization. Why some  conflicts are solved more easily than others seems like a great line of research for people interested in clinical applications of PCT.Â





Richard S. MarkenÂ

“The childhood of the human race is far from over. We
have a long way to go before most people will understand that what they do for
others is just as important to their well-being as what they do for
themselves.” – William T. Powers