[MT] This a continuation of my commenting on Bruce Nevin’s message that heads this thread. I will often, starting with my first comments, refer implicitly to my message on Real Reality and Perceptual Reality in the Science category. http://discourse.iapct.org/t/real-and-perceived-realities/154?u=martint
[BN]In the experimental point of view, the controlled variable, CV, is in the environment. The reference value is also in the environment as an observed regularity in the value of the CV measured over time. This is why control is an observed phenomenon. The theory, with its postulation of theoretical entities like the perceptual signal p, the reference signal r, and the error signal e, explains the observed phenomenon.
[MT] I would call this the Analyst’s view. Both E and S perceive something as being in their environment, which is RR (Real Reality), but what they do perceive is in their own personal PR. The Analyst sees three versions of the variable under test: (1) the subject’s PR CV (the perceived-to-be-in-the-environment version of the perceptual function), (2) E’s perception of something in RR that E perceives S to be able to perceive, and (3) the variable E hypothesizes S to be controlling. This last is in E’s perceptual world and nowhere else, but that’s the point of recognizing the Analyst’s View; the Analyst can see everything relevant to the question at hand.
[BN]In the theoretical point of view (e.g. in our diagrams of a PCT model) the CV is commonly taken to be the perceptual signal p, and it is sometimes argued that the CV cannot be in the environment, it can only be the perceptual signal in the organism…
[MT]Yes, that is the point of my referenced discussion of the relationship between perceived and real reality linked above. There is nothing the CV can be except a projection of the perception into the environment. We have no access to the content of RR other than through the effects that its processes have on our sense organs.
[BN]…One source of this may be from thinking of the comparator as the crucial location at which control takes place. It is there that p is subtracted from the reference signal r. But it’s just as crucial that qo is added to d in the environment, for example, and it is absolutely essential that successive variables around the loop co-vary proportionally. Control is a property of the entire control loop.
[MT]Control is indeed a property of the whole loop, but that loop passes through RR, not the controller’s PR. Also, see my earlier comment about the non-necessity of proportionality between any two variables in the loop. All that is required is that the non-linearities cancel out around the loop. It may be interesting to note that audio engineers interested in high-fidelity reproduction used this property of negative feedback loops to linearize the non-linearities of vacuum tube amplifiers in the 1940s and '50s.
[BN]A second source of this posture that the CV cannot be in the environment may be confusion or equivocation about the nature of the perception that is controlled. As I said earlier, perceptions defined as subjective experiences comprise the entirety of our subjective experience, and this is what we almost always have in mind or tacitly assume when we talk about perceptions in PCT. …
[MT] I think most people interested in PCT think of perceptions in the hierarchy as Bill P described them, not as subjective experiences. Bill used to claim on CSGnet and privately that any subjectively experienced perception must have already been produced in the hierarchy, but the reverse was far from true. Almost all perceptions controlled in the hierarchy are subjectively experienced only when the person controls for being subjectively aware of them. That’s often difficult and requires training. The piano teacher tells you to feel the pressure of your fingers on the keys, better to produce expressive music, for example. It can take a long time before you can do that while actually playing, because you primarily experience the music, not how you produce the music.
[BN]…Our constructivism is sometimes abbreviated to the confrontational maxim “it’s all perception”. If there’s nothing but perceptions, then nothing but perceptions can be controlled, QED. Sounds kind of block-headed when I boil it down to that, but that indeed is what most arguments of this sort boil down to.
[mt] It’s only confrontational when the assertion is not accompanied by at least a pointer to reasons why it is probably true.
[BN]More subtly, we agree that there is something Really Real going on in the universe, and we also agree that our perceptions are all that we can know about it. …
[MT] Don’t forget that it is also only by acting in and on Real Reality that we can influence what or perceptions tell us is in our environment. We don’t know what happens in Real Reality between our acting on it and our perceiving the results. And we cannot act directly on anything in perceived reality.
[BN]* … This opens a conceptual window to be able to say, yes, according to the theory we control the internal perceptual signal p in conformity to the internal reference value r, but these are entities of theory that correspond to the environmental measurement qi and the reference value at which we … *
[MT] Who do you mean by “we” at this point?
[MT]Also one must remember that this qi is delivered by Real Reality to the sense organs and then passes through a complex hierarchy of low-level perceptual function to eventually determine the value of the perception produced by the perceptual function. The set of perceptual functions in E or S specifies what is and can be perceived to be in their PR environment. Analytically, all we know as that p is determined by qi, not that p IS qi or is proportional to qi. (And that’s ignoring the effect of memory that contributes to everything we perceive).
[BN]* … observe that the subject is controlling it. The theory and its elements and relations are themselves only perceptions that bear certain relationships of test and verification (more perceptions) to the universe of subjective experience which is all that we really really have.*
[BN]Observe carefully here how we have to shift deliberately from one point of view to another in order to talk about this articulately. We should not be blind people standing at just one end of the elephant.
[MT] True, but how much of the elephant are you talking about in all this? The Analyst is the one that can know (not sense) everything relevant in the situation. The Analyst has a theory and uses imagined observations to describe what E perceives and does, what S sees and does, and how the feedback loops between them work. Among all else that the Analyst includes in the world of the theory.
[BN]We can go in many directions when we discuss PCT and its ramifications and implications. It is a vastly encompassing theory, and its scope compels us to come at those ramifications and implications from different directions. It is important in all discussions to be clear about these central distinctions of one’s point of view. What role? Subjective perception or perceptual signal p as a theoretical construct?
[MT] Or analyst’s, controller’s, or observer/experimenter’s view? In my presentation to the American Cybernetic Society meeting last June, I included a slide showing four of many possible Analyst’s views of a simple basic control loop: the “circuit View” that we have been discussing here, the “Mechanical View”, the “Information View”, and the “Entropy View”. Each such view shows the same loop, but emphasizing some of its properties while downplaying or totally omitting others. There could be many others, but the point is that the view should, as you say, be carefully identified when trying to be precise about PCT, and “in my father’s house are many mansions” applies equally here. The floor plans of those mansions differ.
[BN]The test for controlled variables is a controlled conflict;…
No conflict at all, as discussed in my first set of comments.
[BN]* … that is, when control has been verified, and the reference value has been identified, the conflict of the disturbance value…*
[MT] Better, perhaps, “the deviation between the disturbed value perceived by E and what E perceives to be the reference value”?
[BN] …* with the reference value is itself a perception, and the experimenter E is controlling that perception.*
[MT] is E controlling that perception or merely using it in controlling for finding a perceptual function that better represents what perception S is actually controlling?
[BN]…* The conflict itself, and its transience, is controlled by E. Prior to that, while guesses as to the CV are still not accurate, E is controlling a perception of conflict between the disturbance value and what she currently imagines the reference value to be.*
[MT] I don’t understand this bit at all, even given my perception that you perceive the TCV as embodying conflict rather than carefully avoiding it. In the example of Bill showing Dag that in controlling his car’s lane position, Dag was also controlling the steering wheel angle. If Bill had been controlling the steering wheel position, they probably would have gone off the road or had a collision. Bill was controlling the force he applied to the wheel, not its angle, which is what Dag was controlling by applying force to the wheel. All Dag had to do was apply a force of the same magnitude as Bill’s but opposite to Bill’s controlled force. No conflict at all. Bill had no wish to make the car go in a particular direction Dag did not want, nor to see the wheel at an angle different from the angle Dag required if the car was to be kept in its lane.
[BN]This is related to collective control as follows: if the disturbance d succeeds in maintaining the CV at a value slightly different from its reference value, such that the outputs of S cannot overcome d or the loop gain in S does not produce sufficient output (S “doesn’t care”), then the deviant value is collectively controlled by E and S.
[MT] Obviously I disagree with the “collective” part of this. What follows is, however, quite distinct from anything preceding.
[BN]Now we come to the reasons for developing hypotheses, testing them, and constructing theories in science which become the organizing framework for developing and testing further hypotheses. It is a systematic way of developing input and output functions and improving our control. But that amounts to nothing if only one person does it. …
[MT] It’s not nothing to the maturing infant or to someone trying to develop a skill. It’s not nothing to the solitary orang-utan learning to navigate the trees, find food, and avoid conflict with other orang-utans. It’s only “nothing” if you want others to learn what one person (or dolphin?) has learned. That’s a different topic from anything earlier.
[BN]…Isaac Newton’s hypothesis of force at a distance as an explanation of regularities observed by Brahe, Kepler, Copernicus, and others, and the mathematics that he invented, would have been as transient as an apple mouldering to compost had he not written and published and had others not read and recognized and developed further consequences of his perceptions. Science inherently involves collectively controlled variables (q.v.). Think of the socially adept Oppenheimer vs. the possibly genius physicist off on a ranch in Montana, unknown and forgotten, as this contrast was portrayed in Malcolm Gladwell’s book Outliers. This is pertinent to the history and current status of PCT.
[BN]*These last three paragraphs each lend themselves to digression into other topics. The point of this present topic has been that, whatever we are discussing, we need to be mindful of who is doing the perceiving (point of view) and whether we mean perception as we experience it or as we model it.
[MT] The last one and a half paragraphs, I do agree with.
[MT]I am sorry to have felt that I should insert so many disagreeing (but I hope not disagreeable) comments in order to control my perception of a theory we call PCT. In much, we do agree, but in perceiving the TCV as a conflict between experimenter and subject, there we disagree, and many of my comments depend on that disagreement. As I have said, I see three basic kinds of view, differentiated by how much each could in principle see of whatever situation is of interest: Controller, Observer/Experimenter, and Analyst. Each of those could be particularized, but at least the main difference should be kept clear in a discussion. The controller’s view is from inside, the Observer/Experimenter’s view is from outside, and the Analyst’s view is an imaginary X-ray view of inside and outside together.
Martin