RM: You know that they are side effects only if you have already got the correct model of the behavior. A correct model of the behavior will be organized around the control of the perceptual variables that are the ones controlled by the organism being modeled. This model will automatically produce the same “side effects” as does the organism in the same circumstances.
AM: Nope. Demonstrably false.
RM: I’d say it demonstrably took too much for granted so you got your signals crossed.
AM: In the tracking task, the controlled variable is the cursor-target distance. When you make a model with the correct controlled variable, you have to fit the model to each individual subject.
RM: Of course. I took that for granted. But I accept your correction. I should have said: A model controlling the correct variables with the appropriately selected control parameters will automatically produce the same “side effects” as does the organism in the same circumstances. How’s that?
RM: The goal of modeling behavior from a PCT perspective isn’t to develop a model that produces the same side-effects of control; it’s to develop a model that accounts for the observed controlling that is being done by the organism. Side effects are simply the aspects of behavior that behavioral scientists pay attention to when they don’t know that behavior is control.
AM: Again, demonstrably incorrect.
RM: Well, to quote a politician a dearly dislike: There you go again;-) In fact, it’s exactly right. And I"ll say it again to prove it: The goal of modeling behavior from a PCT perspective isn’t to develop a model that produces the same side-effects of control.
AM: Look at Bill’s paper on arm control - he reproduced bell-shaped velocity curves and acceleration curves in arm movement, at the same time claiming that they are side effects of control of position and the properties of muscles and really the whole control hierarchy.
RM: Oy vey! He didn’t do this to show how PCT research is done! He did it to show why mainstream research is bankrupt. That is, he did it for the same reason I produced my control model of movement control: to show that the folks who are studying invariant movement trajectories and power laws of movement are completely off base in their research; they are studying irrelevant side effects of control thinking they things tell them something important about behavior when they don’t.
RM: Behavioral scientists want to account for these side effects because they are consistent with their mainstream view of how behavior “works”. Side effects of control are the “red herring” you hear tell of in Bill’s 1978 paper. If you don’t know that behavior is control then you really have no need for PCT, which is a theory of control, not of irrelevant side effect of control.
AM: No, not at all. Behavioral scientists have observed some invariants and laws in behavior, and a correct model of behavior in question must reproduce those side effects.
RM: That’s your conclusion. It’s certainly not mine or Bill’s. Indeed, it’s precisely the opposite of what one would conclude based on an understanding of PCT. What behavioral scientists who understand PCT should do is ignore these things!! They are red herrings, sirens calling you from the rocks of ignorance. Just drop it and start doing research based on an understanding of organisms as perceptual control systems.
AM: The red herring (not in 1978 paper, I think) is simply assuming that the invariants and laws themselves are the controlled variable, the intended result.
RM: “… if one’s purposes [in doing behavioral research]concern objectivized side effects of control behavior, the man-machine blunder amounts to nothing worse than a few mislabelings having no practical consequences. If one’s interest is in the properties of persons, however, the man-machine blunder pulls a red herring across the path of progress” (Powers, 1978).
RM: It doesn’t sound to me like Bill was saying what you take him to be saying. The power law, invariant trajectory profiles, etc are objectivized side effects of control behavior. They are red herrings because they are irrelevant to understanding the behavior of living control systems.
RM: The only way you could know that the power law, invariant trajectory profiles, etc are objectivized side effects of control behavior is because you know what the actor is controlling. So you’ve already explained these side effects once you have explained the behavior in terms of the variables under control.
AM: If there is a bell-shaped velocity, the red herring is assuming that the subject intended to produce the bell-shaped velocity, and then creating an elaborate control architecture that can produce such a velocity profile.
AM: In the power law business, the produced trajectory has specific speed-curvature relationships. The red herring is assuming that the trajectory itself is intended and controlled.
RM: If a researcher assumed that the subject intended (in the PCT sense) to produce the invariant velocity profile or power law then that researcher would know that these are hypotheses about the variables the actor is controlling. So this researcher would would test to see whether the invariant velocity profile or power law are, indeed, controlled variables. And she would find that they are not and would move on to other hypotheses about the variables controlled when people make movements in space.
RM: In fact, the researcher who study these things are mistakenly taking them for intended results. They can’t tell an intended from an unintended result because they are looking at organisms are output generators. What is going on with research on what we know (but the researchers don’t know) are objectivized side effects of control is that researchers think these invariants reveal something important about how people work. So they will keep chasing these red herrings by doing experiments to see how variables affect them in the vague hope that this will reveal something about the mechanisms that produced these phenomena – and they won’t find what they are looking for because the actual explanation is just not what they want to hear: that these are irrelevant side effects of control – boy do they not want to hear that!
RM: Once you understand that organisms are control systems you no longer get seduced by randomly noticed characteristics of behavior – such as velocity profiles or power laws – no matter how invariant or mathematically attractive they are. You just ignore them and start looking for the variables around which the behavior of interest is organized.
RM: With PCT it’s phenomena phirst. If you don’t know that the phenomenon you are dealing with is control – the production of consistent results in a disturbance prone environment – then applying PCT to behavior is putting the cart way before the horse.
AM: Yeah, ok, that doesn’t sound so bad.