[Martin Taylor 2019.01.07.14.21]
[Rick Marken 2019-01-06_14:17:16]
[Frank Lenk 2019.01.05.10:29 CST]
FL: Rick, I agree that the storyabout the wood lice rejects they have a purpose to
seek shade. But the next paragraph, along with its
footnote, modifies that:
RM: I don't think it's particularly productive to tryfind what see like PCT compatible ideas in the work of
others. Indeed, I think it’s counter-productive. My
experience is that in order to see the ideas of others as
being compatible with PCT requires that the essential
elements of Powers work be ignored. In Friston’s case (and
virtually every other case that I’ve encountered) you have
to ignore the fact that a central insight of PCT is that
behavior is control, that it is organized around the control
of a hierarchy of different types of perceptual
variables and that the reference states of these variables
are set autonomously by the system itself. I guarantee you
that there is no other theory of behavior contains any of
these insights.
Different theories have different insights. For the Scientist,
the question is whether the theories are distinguishable in what
they predict should be observed under different conditions.
Friston’s insight doesn’t ignore a fact at the core of PCT,
rather, it uses a fact that PCT ignores. Do these mutual ignorings
mean that both are invalid, that both are valid, or that one or
the other is useful for different purposes? The Scientist asks
whether there are conditions in which both claim to make
predictions of what should be observed, and the claims are
different.
Different theories have different insights. For the Missionary,
the question is whether one insight can be exalted and the other
suppressed. The validity of the insight is irrelevant to this.
Indeed, the nearer the “false” insight is to predicting the same
things as the “true” insight, the more important it is to persuade
people not to even consider the “false” one. The Missionary must,
above all, persuade people that the Scientist is to be ignored.
Examination of the “false” theory, for the Missionary, cannot help
illuminate what is true and good about the “true” theory, but runs
the risk that the examiner of the other theory might be misled
into apostasy. On examination, the other theory might turn out not
to be false even in light of the “true” theory, a potentially
disastrous result, so from the Missionary we get …
RM: My recommendation is to ignore all other theories ofbehavior besides PCT
However, the Scientist might agree with …
and concentrate on the facts that these other theoriespurport to account for. Then see if you can figure out how
PCT would handle these facts. That, rather than looking for
superficial similarities of other theories to PCT, would be
a major contribution to PCT science.
…if the last “PCT” was omitted.
basically correct theory and that when there are critical
experiments that could distinguish between PCT and any other
theory, PCT will win. But my personal objective is not to make
contributions to PCT science so much as to make contributions to
science through PCT. I would like all behavioural scientists
(psychologist, psycholinguists, human factors engineers,
sociologists, economists, political scientists) to know enough of
PCT to be able to see whether it works for their domain of
interest as well as does whatever theory they currently hold; and
I would like to know enough of their theories and data to
understand whether PCT does, as I expect it does, provide an
underlying theoretical basis. But I have no interest in narrowly
contributing to a hermetically isolated “PCT science”. I do not
think such a close-minded "science’ could be other than a
pseudo-science.
In the case of Friston's all-too-similar "false" theory, if you
take the circuit I abstracted from the Seth and Friston paper in
[Martin Taylor 2017.07.11.10.35], relabelling “reference”
↔ “prediction” and “error”<->“surprise” as synonyms,
you find that they both are functionally the same circuit. The
connections differ, in that the S-F circuit sends up to the next
level the reference and the error separately, from which the next
level perceptual function can construct perception as their
difference, while the Powers circuit sends up perception alone.
This does create a potential discriminative experiment. If you
could show that a reference value can be perceived and controlled,
that would favour Friston, but I’m not sure that it is even
possible in principle to show that, since all reference values are
already functions of higher-level outputs in the Powers circuit.
Powers assumed or asserted that reference values and error values
cannot be perceived, at least not in the unconscious hierarchy.
Both Powers and Friston say the error (surprise) can be
controlled or minimized in absolute value (Powers control of
perception to equal reference is equivalent to controlling error
to equal zero), so it is irrelevant whether error can be perceived
independently. Maybe the distinction comes down to choosing the
simpler circuit if there’s no neurological evidence either way and
both circuits perform exactly the same functions under different
labels.
The functional equivalence of the two circuits says nothing about
which insight (minimizing perceptual surprise or controlling
perceptual value) is more valid than the other, even if some
future experiment were to demonstrate that the S-F circuit
represented human brain function better than the Powers circuit.
Martin
···
From my point of view, I have long thought that PCT must be a