RM: Yes, this quotation of Bill’s seems to exactly contradict his statement I posted: “The CV” is the observer’s perception." But later in the post where Bill says what you like – that the state of the perceptual signal is not necessarily the state of the external (observable to others) controlled variable qi – he says this:
BP: The Test requires applying disturbances to the supposed controlled variable, and seeing whether the system’s output action varies so as to have an equal and opposite effect on it. When such a relationship is found, we presume that there is a perception inside the system corresponding to the observable variable being controlled relative to an internal reference signal.
RM: In other words, when we have successfully done the Test we presume that qi (the observable variable being controlled) corresponds to p (the perception inside the system). So that’s two statements saying that qi = p to one saying qi<>p.
RM: My guess is that when Bill says:
BP: “What the system controls, therefore, is the state of the perceptual signal, not necessarily the state of the external (observable to others) controlled variable qi.”
he is referring to how the magnitude of p relates to the magnitude of qi. He is not referring to how the magnitude of qi relates to the type of variable represented by qi. The evidence for this is when Bill says:
BP: If the sensor calibration drifts, the perceptual signal will still be maintained in a match with the reference signal, while the visible controlled quantity’s value changes.
RM: Sensor calibration is not the same as the perceptual functions that define the controlled variables, qi. Sensor calibration (in PCT) defines the quantitative relationship between neural firing rate ( p) and the input to the sensor, qi: in the simplest case p = k*qi. Perceptual functions, on the other hand, define the qualitative nature of qi. For example, a perceptual function that computes t - c defines qi as a perception of the distance between target and cursor.
RM: When calibration drifts, there is a change in k, which changes the quantitative relationship between neural firing rate ( p) and controlled variable (qi). What Bill is saying is that if k drifts lower, for example, then p will remain matching the reference signal but it will do so because the control system will have changed qi (made it large). If qi is t-c then the downward drift of k will produce an increase in the distance between t and c. But this is just a change in the magnitude, not in the nature, of qi. The observer still sees that the system is controlling a perception of t - c; the calibration change results only ina change in the apparent reference state of this perception.
RM: So I see no inconsistency between Bill’s two statements: The one I posted where he said that qi = p and the one Adam posted where he said that qi<>p. There is no inconsistency because qi = p is true qualitatively and qi <> p is true quantitatively; qi = p because qi is an analog of the same aspect of the environment as p; qi<>p to the extent that there is a difference in calibration of the perceptual systems of observer and control system.
EP: Successful control requires that we perceive X well enough and affect it in right manner and strength.
RM: How can you know how accurately a person is perceiving X (in the qualitative sense) when, by your own arguments here, that perception may itself be inaccurate?
Best
Rick