Control and causality (was Re: Homeostasis)

[Martin Taylor 2014.01.30.10.11]

Thanks for your corrections on Copernicus. They ask for a follow-up,

but until (and if) I have something useful to say, I will not be
posting one.
True. Control is an emergent property of the structure of a control
loop. But that is not relevant either to the role of causality in
control or to the role of feedback in the operation of a spring.
You are new (at least as a contributor) to this list, so you may not
be aware that the word “causality” has a history of
misinterpretation. For a long while, even Bill Powers could not
convince Rick that in the usual description of an elementary control
loop
the elements (links and functions) were causal systems. In other
words, Rick forcefully asserted that in this structure p was not
causally related to s, or e to r and p. I’m not sure that eventually
he was not “convinced against his will, and is of the same opinion
still”.
There’s a related issue, which is that in causal systems the effect
must follow the cause if they are spatially separated, even by an
infinitesimal amount. This has led to a different persistent error.
In a control loop all the causal influences operate simultaneously.
p is affecting e while s is affecting p (True). This has led some to
state a completely different set of conditions, of which this is a
member “The value of p is influenced by the present value of e”
(False), or “The values all around the loop at any one moment must
simultaneously satisfy all the causal equations of the links in the
loop” (True but usually misinterpreted, as discussed below).
This last statement leads to what I like to call a “static analysis”
of the loop. Bill Powers talked about it as the case in which the
disturbance and reference vary infinitely slowly, which is the same
as being static. We see the static analysis or something like it
quite often on CSGnet, where it is sometimes misapplied to the
situation in which d and.or r change at rates that matter, a mistake
Bill very rarely made, if ever. Here’s the canonical form of the analysis, taking P() and G() to be
simple multipliers P and G.
p = Ps = P(o + d) = P*(Ge + d)
= P
(G*(r-p) +d)
= PGr + Pd - PGp (1)
Up to this point rapid variation of d and r don’t cause any problem,
though when you combine their rapid variation with transport lag
over the links there is a potential problem, one that becomes
manifest in the next move in the canonical static analysis, which is
to combine the expressions in p:
p + P
Gp = PGr + Pd (2) which is wrong because the two values of p existed at different
times. The analysis continues:
p*(1+PG) = PGr + Pd p = PGr/(1+PG) + Pd/(1+PG) (3)
And if P*G > 1 and G >P, we get the result usually cited
p = r/(1+ 1/loop gain) ) + d/(1 + loop gain) (4)
which, for loop gain >> 1 leads to
p = r

CanonicalCtlLoop2.jpg

···

(I changed the Subject line because the thread seems to have gone
a long way from homeostasis).

From Angus Jenkinson, 2015, 1,30,11:39GMT

          The technical discussion

between Rick and Bruce is very interesting. I would like
to insert another parameter. It is one that interests me
more because I am primarily working in the organic realm
and human behaviours. What most interests me about PCT is
that it involves viable organisms actively managing their
behaviours to maintain intended paths to goals (by
controlling perceptions). There is nothing in a spring or
a pendulum like this. Moreover, while causality operates
(I think) more or less as the traditional view of
causality, at least in immediate proximity to the effect,
in PCT in the human realm an utterly different process
occurs of actively cancelling perturbations (external
causal factors). PCT is not being applied to springs.

  What most interests me about PCT is that it

involves viable organisms actively managing their behaviours to
maintain intended paths to goals (by controlling perceptions).
There is nothing in a spring or a pendulum like this.

operation****effect

  while causality operates (I think) more or

less as the traditional view of causality, at least in immediate
proximity to the effect, in PCT in the human realm an utterly
different process occurs of actively cancelling perturbations
(external causal factors). PCT is not being applied to springs.

FROM Angus Jenkinson, 2015,1,30, 19:30 GMT

Martin, thank you for your kind efforts to explain and advise me on what has been a recurrent theme of my inquiry here. I do appreciate it and the detailed analysis.

You say that: “For a long while, even Bill Powers could not convince Rick that in the usual description of an elementary control loop the elements (links and functions) were causal systems. In other words, Rick forcefully asserted
that in this structure p was not causally related to s, or e to r and p. I’m not sure that eventually he was not "convinced against his will, and is of the same opinion stillâ€?.

If that was the case he would find himself joined by me and I think others. The exceptional genius of this theory, which if you are right its author himself denies, is to substitute for the dominant ideology of the last 4 centuries
a fundamental new episteme that offers (in the human realm at least and most likely the whole biological realm) at least the beginnings of an understanding of autonomy, and purposiveness. It is a paradigmatic shift of earthquake proportions and it is understandable
that this is difficult to grasp by outsiders, and moreover that it is fearful to propose, given the dominance of the orthodox perception. By the very principles of PCT, PCT looks wrong and is therefore a perturbation that needs cancelling. It would look unscholarly,
when it is clear from this forum that the members are exceedingly scholarly.

My inquiries have been also along the line of wondering why the basic PCT stance “at the top lovel� is not maintained “all the way down�? The analysis kept looking like a causal explanation. I begin to get why, perhaps.

Am I heretical to PCT as well as the orthodoxy?

[Martin Taylor 2014.01.30.15.02]

FROMÂ Angus Jenkinson, 2015,1,30, 19:30 GMT
Martin, thank you for your kind efforts to explain and advise me on what has been a recurrent theme of my inquiry here. I do appreciate it and the detailed analysis.
You say that: “For a long while, even Bill Powers could not convince Rick that in the usual description of an elementary control loop the elements (links and functions) were causal systems. In other words, Rick forcefully asserted that in this structure p was not causally related to s, or e to r and p. I'm not sure that eventually he was not "convinced against his will, and is of the same opinion still�.
If that was the case he would find himself joined by me and I think others. The exceptional genius of this theory, which if you are right its author himself denies, is to substitute for the dominant ideology of the last 4 centuries a fundamental new episteme that offers (in the human realm at least and most likely the whole biological realm) at least the beginnings of an understanding of autonomy, and purposiveness.

Quite true, but (apart from your first sentence and the idea of Bill's denial) not in any way contradictory to the statement that every link in the PCT structure is causal. The genius of Bill Powers was to recognize the emergent property of the _structure_ of causal connections (control), not to deny physics.

It is a paradigmatic shift of earthquake proportions and it is understandable that this is difficult to grasp by outsiders, and moreover that it is fearful to propose, given the dominance of the orthodox perception. By the very principles of PCT, PCT looks wrong and is therefore a perturbation that needs cancelling. It would look unscholarly, when it is clear from this forum that the members are exceedingly scholarly.
My inquiries have been also along the line of wondering why the basic PCT stance “at the top lovel� is not maintained “all the way down�? The analysis kept looking like a causal explanation. I begin to get why, perhaps.

In what way do you perceive it as not being maintained "all the way down"?

Am I heretical to PCT as well as the orthodoxy?

Perhaps not so much heretical as being partway on the journey of understanding. As are we all.

Martin

Angus Jenkinson, 2015,1,30, 20:35

Martin: Quite true, but (apart from your first sentence) not in any way contradictory to the statement that every link
in the PCT structure is causal. The genius of Bill Powers was to recognize the emergent property of the structure of causal connections, not to deny physics.

This is not physics, it is psychology.

that’s exactly the problem I was referring to

AJ My inquiries have been also along the line of wondering why the basic PCT stance “at the top lovel� is not maintained “all the way down�? The analysis kept looking like a causal
explanation. I begin to get why, perhaps.

Martin: In what way do you perceive it as not being maintained “all the way down”?

The account of perceptual control seems not to reach to cellular level – I have an existing postt out on this to Rick, awaiting his response

[Martin Taylor 2015.01.30.15.58]

Ah. I see. You are a stage earlier in your acceptance of PCT than I

had thought. Yes, there is a normal progression of people newly introduced to
PCT. They (including me) start by thinking that “control” in PCT is
a metaphor. It takes a while to realize that it is no metaphor, but
is exactly the same as in engineered control systems. Psychology
can’t deny physics, though psychologists might. Bill’s genius was
that without prompting he made the realization that psychological
control IS physical control, and could see that it explained so much
of psychology. It took me probably a month to believe it after
discovering the predecessor of CSGnet, even though I had previously
developed a theory that turned out to be a special case of PCT.
Another way to describe Bill’s great insight is that there’s no
magic in psychology. Biological systems are subject to the same
natural laws as is the rest of the Universe. We may not know all
those laws, but that is no reason to exempt biology from physical
laws that appear to apply to everything else we know about. Bill
believed this, and that belief allowed him to think of and to
continually develop PCT.
It reaches to cellular level if you want it to. The question is how
deep you want to delve, not how deep the theory probes. Over the
history of CSGnet there have been several time when intracellular
PCT has been discussed. Using physics as a metaphor, do you want to
worry about quarks when you are trying to get salt from seawater?
Don’t confuse PCT with the specific hierarchy that is often talked
about as being PCT. The hierarchy is intended to account for
phenomena we experience, but the theory deals with how control works
wherever it is found.
Martin

···
        Angus Jenkinson,

2015,1,30, 20:35

Martin:Â Quite
true, but (apart from your first sentence) not in any
way contradictory to the statement that every link in
the PCT structure is causal. The genius of Bill Powers
was to recognize the emergent property of the
structure of causal connections, not to deny physics.

This is not physics, it is psychology.

that’s exactly the problem I was referring to

AJÂ My inquiries have been
also along the line of wondering why the basic PCT
stance “at the top lovel� is not maintained “all the way
down�? The analysis kept looking like a causal
explanation. I begin to get why, perhaps.

                  Martin:Â In

what way do you perceive it as not being maintained “all the
way down”?

    The account of perceptual control seems not to reach to

cellular level – I have an existing post out on this to Ricck,
awaiting his response

From Angus Jenkinson, 2015, 1,30,23:23 GMT

Martin: Quite
true, but (apart from your first sentence) not in any
way contradictory to the statement that every link in
the PCT structure is causal. The genius of Bill Powers
was to recognize the emergent property of the
structure of causal connections, not to deny physics.

AJ This is not physics, it is psychology.

that’s exactly the problem I was referring to

Martin: Ah. I see. You are a stage earlier in your acceptance of PCT than I

had thought. Yes, there is a normal progression of people newly introduced to PCT. They (including me) start by thinking that “control” in PCT is a metaphor. It takes a while to realize that it is no metaphor, but is exactly the same as in engineered control systems. Psychology can’t deny physics, though psychologists might. Bill’s genius was that without prompting he made the realization that psychological control IS physical control, and could see that it explained so much of psychology. It took me probably a month to believe it

Thanks again for your POV and concern. I should confirm that have had a few years in this territory, and I rid myself of some of assumptions 30+ years ago. I no longer feel the need to reduce everything to a 400 year old physics. I respect your knowledge which I am sure in some realms vastly exceeds mine, but such things usually work mutually. The imposition of a special species of physics outside its proper domain is unwarranted.

To take your phrase, " psychological control IS physical control”, it means that psychology (not some abstractions but an activity of an organism) controls physics (whatever base level&nbs
p;entitiies are transformed and moved) not the other way round, if it means anything at all.

What do you take it to mean that an organism cancels perturbation? Or is this not key to PCT for you?

[Martin Taylor 2015.01.30.22.59]

There's the problem. There is NO special species of physics involved

in PCT. Nor is there any part of the world in which physics is out
of its domain. The assumption that there is may be related to your
apparently treating control as a metaphor, rather than as a general
process that acts in psychology just as it does everywhere else.
What does “psychology controls physics” mean? If you mean that all
our sciences are just models created from the results of our
perceptual control efforts in our environment, then I can’t
disagree. But the rest of your sentence doesn’t sound as though
that’s what you mean.
What I meant by saying “psychological control IS physical control”
is that there is no magic in control when a perceptual variable is
brought near its reference value by actions on the environment. It’s
a normal control process. All of the individual processes in the
links of the loop are described by the appropriate scientific
discipline operating in its normal domain, and when that discipline
concerns forces and motion, it is physics. Internally to the
organism, chemistry, biology, etc., are more appropriate, but they
all are based in physics. No psychology can avoid the applicability
of the laws of thermodynamics, for example. I refuse to believe in
magic as a principle on which to base a science.
“Psychological control IS physical control” means that all the
analytical apparatus developed for engineered control systems
applies equally to biological control systems. As I said, Bill’s
genius was to recognize that fact without having had anyone prompt
him or guide him to that conclusion. Many people, including me, had
the necessary background and knowledge to have had the same insight,
but we didn’t. Bill did.
No. No organism can cancel perturbation. The best that can be done
is to reduce the effects of perturbation to within limits that allow
the organism to continue to operate effectively. One key to PCT is that the variable stabilized by an elementary
control unit is internal to the organism, not out in the
environment. In PCT that variable is called a perceptual signal. The
theory is PERCEPTUAL Control Theory. A secondary key is that the
reference value for that variable is dynamically influenced by the
actions that stabilize other internal variables we call perceptual
signals. A third key is that the perceptual signals that are
controlled must relate to simple or complex functions of sensed data
from the environment that correspond to environmental opportunities
or dangers that would affect the continued effective operation of
the organism. Martin

···

From Angus Jenkinson, 2015, 1,30,23:23 GMT

Martin: Quite true, but (apart from your
first sentence) not in any way contradictory to
the statement that every link in the PCT
structure is causal. The genius of Bill Powers
was to recognize the emergent property of the
structure of causal connections, not to deny
physics.

AJ This is not physics, it is psychology.

that’s exactly the problem I was referring to

          Martin: Ah. I see. You

are a stage earlier in your acceptance of PCT than I had
thought. Yes,
there is a normal progression of people newly introduced
to PCT. They (including me) start by thinking that
“control” in PCT is a metaphor. It takes a while to
realize that it is no metaphor, but is exactly the same
as in engineered control systems. Psychology can’t deny
physics, though psychologists might. Bill’s genius was
that without prompting he made the realization that
psychological control IS physical control, and could see
that it explained so much of psychology. It took me
probably a month to believe it

              Thanks again for

your POV and concern. I should confirm that have had a
few years in this territory, and I rid myself of some
of assumptions 30+ years ago. I no longer feel the
need to reduce everything to a 400 year old physics. I
respect your knowledge which I am sure in some realms
vastly exceeds mine, but such things usually work
mutually. The imposition of a special species of
physics outside its proper domain is unwarranted.

To take your phrase, " psychological
control IS physical control”, it means that psychology (not
some abstractions but an activity of an organism) controls
physics (whatever base level&nbs p;entitiies are
transformed and moved) not the other way round, if it means
anything at all.

    What do you take it to mean that an organism cancels

perturbation? Or is this not key to PCT for you?

[From Rick Marken (2015.01.30.1050)]

CanonicalCtlLoop2.jpg

···

Martin Taylor (2014.01.30.10.11) to Angus Jenkinson

MT: You are new (at least as a contributor) to this list, so you may not

be aware that the word “causality” has a history of
misinterpretation. For a long while, even Bill Powers could not
convince Rick that in the usual description of an elementary control
loop

the elements (links and functions) were causal systems. In other

words, Rick forcefully asserted that in this structure p was not
causally related to s, or e to r and p. I’m not sure that eventually
he was not “convinced against his will, and is of the same opinion
still”.

RM: I wish you wouldn’t use your rather hopeful interpretations of what Bill said to me in the past to argue against me in the present. And then I won’t use my perfectly accurate interpretations of what Bill said to me in the past (on and off the net) to do the same to you.

RM: In fact, I have never needed to be convinced that the functional relationships between variables in a control loop are causal. The only thing I can recall Bill having to “convince” me of was that it is wrong to deny that there is a causal path from disturbance (d) to output (o). I wasn’t really denying that there is a causal path from d to o; I was just denying (and still do) that d is the sole cause of o since the cause of o is the perceptual variable § which is the combined result of d and o. So d is never even perceived by the system; all that is perceived – and, therefore all that could be the cause of o – is the combined result of o and d, which is p

RM: But talking about whether o or d or even the combination of both is the cause of o really misses the point. The point of a control loop is that p is kept at the reference value, r, protected from the effect of disturbances. So, as far as causality goes, the most important causal relationship in a control loop is the one that goes from r to p. This causal relationship – p = r – is the fundamental causal relationship in PCT. It says that organisms (living control systems) are acting to cause their perceptions, p, to match their own autonomously set references, r, for those perceptions. So understanding the behavior of organisms is a matter of learning what perceptions, p, organisms are trying to cause for themselves. That is the basic goal of PCT research.

MT: p = r

RM: That’s what I’m talkin’ about! That is the most important causal connection in PCT, the one going from reference to perception.

Best

Rick

Richard S. Marken, Ph.D.
Author of Doing Research on Purpose.
Now available from Amazon or Barnes & Noble