Behavior and Control Theory

[From Rick Marken (2015.10.30.1645)]


Martin Taylor (2015. –

  MT: PS. In one of the messages Bruce

referred to “You can’t tell what someone is doing by observing
what they are doing” as evidence that “behaviour” should include
the whole of control. I would read the mantra differently, without
using the word “behaviour” or any PCT-technical words: “You can’t
tell what someone wants to achieve by observing their actions.” In
that, to make it technical, I would make these substitutions:
“what someone want to achieve” -> “what perception someone is
controlling with what reference value”, and “actions” ->

RM: I think you confuse “technical” with “theoretical”. A more technical (and non-theoretical) restatement of “You can’t tell what a person is doing by just looking at what they are doing”" would be “You can’t tell whether a variable is under control (whether it is a controlled variable) by observing how it varies or how the actions that influence it vary”. For example, you can’t tell whether the angle of a car door is under control by observing that it moves from 0 to 80 degrees relative to the side of the car or that it went to 80 degrees as a result of the pushing actions of the driver. The opening of the door may by the rest of the wind or an accidental side effect of the driver pushing the door with his backside while reaching for something inside the cab.

RM The way to tell tell whether or not a variable, such as the angle of the door, is under control is to see whether it is being brought to a reference state and maintained there, protected from the effects of disturbances. The reference states of variables like the angle of a car door are the hallmark of control. And these reference states exist in fact, not in theory. Here is what Powers said about it:

WTP: “The existence of these reference states is not conjectural; once behavior has been defined in terms of an appropriate variable, such reference states always exist. They can be discovered experimentally, and defined in terms of observable relationships. Whether or not they should exist according to anyone’s theory, they do exist”. (p. 175 LCS I)

RM: An “appropriate variable” is, of course, a “controlled variable”, such as the angle of the car door, since reference states exist only for controlled variables. So this little quote shows that Powers was comfortable defining behavior in terms of “controlled variables” (as he does in Table 1 on p. 172 of LCS I and as we do in the “Behavior as Control spreadsheet”). The quote also makes clear that the reference states of controlled variables exist as actual phenomena. That is, they exist in fact, not in theory. The last sentence – that whether or not they should exist according to anyone’s theory, they do exist – is clearly an allusion to the fact that reference states for controlled variables should not exist according to the prevalent causal theories of behavior. But they do exist according to PCT. Indeed, it was Powers’ observation that reference states are real behavioral phenomena that led to the development of PCT. As Powers says:

WTP: In these reference states we have the heart of the problem, to which control theory is addressed. (p. 175 LCS I)

RM: PCT was developed to explain the fact that organisms act to bring variables to reference states and keep them there, protected from disturbance. That is, PCT was developed to explain the fact of control. Since the controlling done by living systems is called purposeful behavior we can say that PCT is a theory that is designed to explain the purposeful behavior of living systems, the central feature of which is the existence of reference states of controlled variables.

RM: Since other psychological theories either ignore or deny the existence of reference states – that is, they ignore or deny the fact that behavior is control (purposeful) – those theories don’t explain the same phenomena that PCT explains. Since this is the case, trying to “sell” PCT to psychologists as a better theory of behavior than the one they have is rather misleading. The first step in convincing psychologists that PCT is a better theory of behavior than any they have is to convince them that their theories fail to account for what is most important about behavior: it’s purpose, in the form of reference states of controlled variables. The behavior psychologists are trying to explain is the actions that maintain controlled variables in their reference states, protected from disturbance. So once you understand how organisms control – how they keep controlled variables in reference states – and you also understand why they act in certain ways in apparent response to certain environmental events (disturbance resistance).

RM: So PCT explains a behavioral phenomenon unknown to most psychologists – the reference states of controlled variables – and one that is known to them – the relationship between stimulus “inputs” (disturbances; IV) and behavioral “outputs” (actions that compensate for disturbances: DV).

RM: This is what is important – knowing that PCT explains the reference states of controlled variables (the purpose of behavior) and other theories don’t – more important than getting wrapped around the axle trying to find the “correct” definition of a word (behavior) that is an informal term that refers to the “doings” of living and non-living things.



Richard S. Marken
Author of Doing Research on Purpose.
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