# Rick on (off) Shannon

**URL:** <http://discourse.iapct.org/t/rick-on-off-shannon/9982>\
**Category:** CSG1992\
**Created:** [December 17, 1992, 3:44pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982 "1992-12-17T15:44:11Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![\_Martin\_Taylor](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/_/a9adbd/32.png) [@\_Martin\_Taylor](http://discourse.iapct.org/u/_Martin_Taylor)\
**Post date:** [December 17, 1992, 3:44pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982/1 "1992-12-17T15:44:11Z")

</div>

[Martin Taylor 921217 10:40]  
(Rick Marken 921216 sometime)

I really can't let Rick's latest non-sequitur go unchallenged:

> Bill P.'s  
> important observation was that perception is one link in a  
> causal loop in which we are all locked -- a loop that obviates  
> Shannon's concerns about reliable transmission since, in living  
> systems, perception is not the "start" of communication (or the  
> "end", for that matter); it is both the start and the end at the  
> same time.

Every piece of the loop is constrained by Shannon's observations/theorems.  
If (like Rick) you don't understand them, you are doomed not to uinderstand  
PCT.

Martin

---

<div class="post-metadata">

**Author:** ![Marken\_Richard\_S1](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/m/977dab/32.png) [@Marken\_Richard\_S1](http://discourse.iapct.org/u/Marken_Richard_S1)\
**Post date:** [December 21, 1992, 10:30pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982/2 "1992-12-21T22:30:34Z")

</div>

[From Rick Marken (921221 1300)

Martin Taylor (921216 17:40) --

> The argument was roughly (as seen from my side): if there is an intrinsic  
> variable (i.e. a variable outside the main hierarchy, in a Bill-P-type  
> reorganization hierarchy) with a reference level R and perceived level P,  
> giving error E, then I assert that the controlled variable is P. Rick  
> asserts that it is d(E^^2)/dt.

If this were the argument then there would have been no argument.  
Remember, I?m the guy who posted that little proof that the  
ERROR VARIABLE IN A CONTROL LOOP is not controlled.  
Why the hell would I have argued that error IS controlled?  
Unfortunately, I have saved none of our private posts but I  
remember the argument quite differently -- I thought that  
you were saying that intrinsic error (or some transform thereof)  
was controlled in reorganization. Now you say it the perception  
of the intrinsic variable that is controlled -- which (of course) is  
correct and I agree.

If you have saved the private posts, Martin, then you could post  
them and clear this all up. But even without them it is clear from  
my post to the net that I NEVER suggested that ?d(E^^2)? was  
controlled -- where E (in your comment above) is the error in  
the system controlling the intrinsic variable, P. When I said that  
d(e^2) is controlled, I made it quite clear that this was a  
perceptual variable -- representing perception of error in  
OTHER control systems. And I never made a big deal about  
what the form of the function was -- it?s a perceptual function  
and determining it is best left to research and modelling.

> Now what might be an intrinsic variable. I used blood CO2 concentration,  
> but I'm quite happy with overall error in the main hierarchy. But if  
> overall error is to be used, Rick's formula won't work.

Well, I won?t conceed that until I see it modelleed. But  
I never made an issue of what the damn function is that  
transforms overall error into a perceptual measure of error --  
I was just saying that ?error in the main hierarchy? can be  
a controlled intrinsic variable. Apparently you are happy  
with that; if you had written the above paragraph N posts  
ago we could have saved all this useless blather.

> Rick was talking  
> about error in the hierarchy AS an intrinsic variable, but using an  
> expression that couldn't work, whereas when I used the word "error" I  
> was referring to error IN an intrinsic variable (which might well be  
> overall error magnitude in the main hierarchy).

Well, then why did you just now (see above) say ?Rick  
asserts that it is d(E^^2)/dt.? that is controlled; where E  
is error in the control system controlling the intrinsic  
variable (according to your notation)? If you don?t  
want to have confusion, don?t be confusing.

I find this little misunderstanding (if that?s what it was)  
particularly annoying because it led Bill Powers to write:

> I think I have to side with Martin Taylor on this one, Rick. In a  
> simple reorganizing model, e^2 might be a suitable driving signal  
> for the rate of reorganization. But that isn't the controlled  
> variable. It's the error signal.

Again -- I?M THE ONE WHO WROTE THE DAMNED PROOF that  
error is not controlled; of course e^2 is not controlled -- unless it  
is PERCEIVED by another control system which can act in ways that  
have systematic effects on that perception. Why in the hell would any-  
one imagine that I was arguing that an error signal in a control loop is  
controlled??? How could you imagine that this was my argument,  
Martin???

Martin Taylor (921217 10:40)

> I really can't let Rick's latest non-sequitur go unchallenged:

> Every piece of the loop is constrained by Shannon's observations/theorems.  
> If (like Rick) you don't understand them, you are doomed not to uinderstand  
> PCT.

Well, you got me there Martin (I think I understand Shannon?s  
observations/theorems ok, though not nearly as well as you). But since  
you understand PCT so well (thanks to your understanding  
of information theory) why haven?t I seen any of your PCT research or  
modelling work in the last decade or so,while I?ve been working on PCT?  
About the only work I ever found was done by Bill Powers. I did find  
some stuff by Carver/Scheier types who didn?t know the difference between  
a controlled variable and a reference signal. I also saw lots of tracking  
studies by people who?s goal was to figure out how target inputs cause  
response outputs. But I never found any research (other than Bill?s) that  
was based on a deep understanding (like yours) of PCT. In the last few  
years I?ve seen some great stuff done by people like Tom Bourbon (and  
his students), Clark McPhail, and Chuck Tucker and a couple others.  
But I never ran across anything of yours. Since you REALLY understand  
PCT I bet your stuff is great. I?d really like to see it; especially the  
stuff  
that shows how important information theory is for doing PCT research  
and modelling.

Martin, I count a statement like this:

> If (like Rick) you don't understand them, you are doomed not to  
> uinderstand PCT.

as a personal insult. It is a disturbance to the level at which I like  
to maintain the perception of my own self esteem. I?m sure you  
will say that it was not meant as an personal attack -- and I?m prepared  
to believe that; but I don?t really care -- a disturbance is a disturbance,  
regarless of the intent of the source; so here is a little compensating  
action (in lieu of going up a level):

If (like Martin) you don't undertand PCT, DON'T TRY TO  
TEACH IT. Those of us who do understand it -- and  
have done the grunt work necessary to grasp the  
fundementals -- find condescending tutorials on PCT  
to be cloying.

Best regards

Rick (what else would you expect from a loose canon?)  
Marken

---

<div class="post-metadata">

**Author:** ![\_Martin\_Taylor](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/_/a9adbd/32.png) [@\_Martin\_Taylor](http://discourse.iapct.org/u/_Martin_Taylor)\
**Post date:** [December 21, 1992, 11:29pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982/3 "1992-12-21T23:29:24Z")

</div>

[Martin Taylor 921221 18:00]  
(Rick Marken 921221 1300)

Rick ,  
Welcome back from your trip. I'm sorry it didn't go well, and left  
you in a bad mood, when you saw my little twitting of you. I didn't intend  
you to take it as an insult, any more than you presumably intended  
your comment to me a couple of weeks ago as an insult, when I took it  
badly. Sorry you took it that way.

I think I posted a reasonable summary of the interactions, but you  
seem to think I misled the other readership. I had asked you to post  
everything, to avoid that kind of problem. Now it seems that to preserve  
honour (a rather silly concept, but we tend to have reference levels  
for that kind of thing), I have to waste net bandwidth by reposting  
the discussion entire.

Either I still misread what you posted, or you misread what I said.  
It still seems to me that you were arguing for precisely what I claimed  
in my summary, which you now claim is ridiculous.

> **···**
>
> ----------------------
> 
> > If (like Martin) you don't undertand PCT, DON'T TRY TO  
> > TEACH IT. Those of us who do understand it -- and  
> > have done the grunt work necessary to grasp the  
> > fundementals -- find condescending tutorials on PCT  
> > to be cloying.
> 
> I have a feeling it is my various attempts to look for the fundamentals  
> that you (Rick) find cloying (should I guess at threatening?). I know very  
> well that I don't understand PCT. I don't think anyone on the net claims  
> to except you, least of all Bill P. I'm sorry that you don't want to  
> look beyond the behaviour of control hierarchies to see how and why  
> they work in addition to what they do. I hope that "those of us who do  
> understand it" is not a large group who find my postings "cloying."
> 
> One of the best ways of learning is to try to teach. But I don't think that  
> I have ever been trying to do that (except locally here at DCIEM). What I  
> have tried to do is to develop the implications of PCT, to enquire as to  
> problems that seem to arise, to get at the basics of PCT. If you don't  
> like it, I'll quit, and just work with our group here at DCIEM. There's  
> no benefit to me in finding an automatic rejection of my ideas when they  
> are proposed to the net. It is really Bill P's encouragement more than  
> anything else that keeps me going--that, and my belief that PCT is the  
> Newtonian revolution in psychology. But the latter part is something  
> I can develop on my own, or in private communication with Bill P and my  
> local collaborators.
> 
> ------------------------  
> Here are the postings, so far as I still have them.
> 
> Martin
> 
> # ===========================
> 
> # (I don't seem to have the first mail, to which this is Rick's response)
> 
> > From Marken@courier4.aero.org Thu Dec 10 14:30:23 1992
> 
> Subject: Re: Rick's proof: error not controlled  
> To: @MVE.AERO.ORG:mmt@ben.dciem.dnd.ca  
> Status: RO
> 
> Martin
> 
> You seem to have sent this to me personally -- so I am sending it  
> back to you personal (I think; it's often hard for me to tell where  
> mail came from when I'm using this mail system). But I'd be happy  
> to have the put on the net -- as usual.
> 
> > I have no complaint about your proof. Different people see things better  
> > from different viewpoints. I thought I was buttressing, not caviling.
> 
> OK. What made me think that you disagreed with the proof was the  
> following:
> 
> > > Where in the world (take the literal meaning of that expression) is the  
> > > possibility for disturbing the error in an ECS?
> 
> Now you say:
> 
> > A disturbed error signal is not an error signal as defined.
> 
> If you cannot disturb error (and again I point to Bill's diagram to  
> show that you can) then my proof is invalid because it is based on  
> the idea that o = k(r-p+de) -- were de is the disturbance to error.
> 
> As I mentioned in my post with the equations, if the perceptual signal  
> were disturbed in the same way (by having a disturbance added to  
> the neural signal itself) the perceptual signal would still be controlled  
> (made to equal the reference -- ie. the disturbance would have no effect.  
> So again, while I agree with your conclusions, I disagree with the  
> arguments you use to come to them.
> 
> > I suppose I would agree that error could be controlled if it were to be  
> > provided as input to the perceptual input function of a control system that  
> > maintained the error at some reference level.
> 
> As you will see in a reply I plan to make to Greg, there is no  
> supposing necessary in this case. The error signal (which is now  
> a perceptual input to a control system) would DEFINITELY be  
> controlled.
> 
> > But what on earth would that  
> > do other than enforce a situation in the ECS whose error was being
> 
> controlled
> 
> > that would ordinarily arise only through unresolvable conflict. I can't  
> > see why any hierarchy would include such a mechanism--but I suppose there  
> > might be a reason somewhere.
> 
> But this is precisely the way reorganization works. It controls errors by  
> changing properties of the control system itslef (like its perceptual  
> function) -- properties which are presumably responsible for the conflict  
> that is creating the chronic error. Reorganization is control of error  
> (where error is the input perceptual variable to the reorganization control  
> system) -- and control is effected by acting on properties of the control  
> systems themselves. Since there is no way to know HOW to change the  
> control systems in order to reduce error, there must be a random  
> componenet to this kind of control -- Bill has modelled as a control  
> system where the RATE at which random changes occur is inversely  
> proportional to the perceived value of error.
> 
> Best
> 
> # Rick
> 
> > From mmt Thu Dec 10 16:45:11 1992
> 
> To: Marken@courier4.aero.org  
> Subject: Re: Rick's proof: error not controlled  
> Cc: ./marken  
> Status: RO
> 
> Rick,
> 
> As usual, we were talking a little at cross purposes. There's no real  
> argument. You were assuming that there might be some way that a disturbance  
> could be applied to the error within an ECS, and when you mention electrodes,  
> that can be true. I was working within the normal hierarchy, in which the  
> only inputs to an ECS are through its perceptual input function and its  
> reference inputs, and within that frame, there's no way to apply a "de".  
> That doesn't argue against your proof at all. If(x) then (y) is the proof.  
> Not(x) does not say not(y).
> 
> On a different topic, you say:
> 
> > > But what on earth would that  
> > > do other than enforce a situation in the ECS whose error was being  
> > > controlled  
> > > that would ordinarily arise only through unresolvable conflict. I can't  
> > > see why any hierarchy would include such a mechanism--but I suppose there  
> > > might be a reason somewhere.
> > 
> > But this is precisely the way reorganization works. It controls errors by  
> > changing properties of the control system itslef (like its perceptual  
> > function) -- properties which are presumably responsible for the conflict  
> > that is creating the chronic error.
> 
> Reorganization may well work this way. (All we know experimentally is that  
> Bill says that my approach to reorganization is the only one he knows to  
> work by simulation, and then only in respect to gain functions; even if we  
> eventually discover various ways in which it COULD work, we won't know  
> that it DOES work this way). But the thing I was saying was that however  
> reorganization works, it seems unlikely to develop stable systems that do  
> useless or obstructionist things.
> 
> > Reorganization is control of error  
> > (where error is the input perceptual variable to the reorganization control  
> > system) -- and control is effected by acting on properties of the control  
> > systems themselves. Since there is no way to know HOW to change the  
> > control systems in order to reduce error, there must be a random  
> > componenet to this kind of control -- Bill has modelled as a control  
> > system where the RATE at which random changes occur is inversely  
> > proportional to the perceived value of error.
> 
> Actually, what Bill has done seems to be a little more complex. He has  
> found that the derivative of the squared error is a better criterion.  
> In our experiments, we have been planning to use K1(e^^2)+K2(e\*de/dt),  
> where de/dt is the derivative of error (2e\*de/dt is the derivative of  
> e^^2). We think that both error and the rate of increase of error are  
> important. It shouldn't matter if the error is momentarily large, provided  
> it is decreasing well. When I say "criterion" I mean the Poisson rate of  
> reorganization events.
> 
> Does this help to reduce the cross of our purposes?
> 
> # Martin
> 
> > From Marken@courier4.aero.org Tue Dec 15 18:54:38 1992
> 
> Subject: Re: Rick's proof: error not controlled  
> To: @MVE.AERO.ORG:mmt@ben.dciem.dnd.ca  
> Status: RO
> 
> Martin
> 
> > Actually, what Bill has done seems to be a little more complex. He has  
> > found that the derivative of the squared error is a better criterion.
> 
> You mean, as the variable controlled by the reorganization system, right?
> 
> > In our experiments, we have been planning to use K1(e^^2)+K2(e\*de/dt),  
> > where de/dt is the derivative of error (2e\*de/dt is the derivative of  
> > e^^2). We think that both error and the rate of increase of error are  
> > important. It shouldn't matter if the error is momentarily large, provided  
> > it is decreasing well. When I say "criterion" I mean the Poisson rate of  
> > reorganization events.
> 
> Now I don't understand. The "Poisson rate.." is a criterion? It sounds like a  
> variable. Why would your model be concerned about the "Poisson rate of  
> reorganization events"? It's not controlling that rate, is it? Bill's model  
> controls the derivative of the squared error(you are correct about this,  
> I believe); it controls this variable by changing some parameter of the  
> systems  
> that are experiencing the error; the time between such changes increases as  
> the  
> difference between the derivative of the squared error and zero decreases. As  
> a  
> side effect the Poisson rate of reorganization events changes during the  
> course  
> of reorganization.
> 
> At least, that was my impression this summer in Durango.
> 
> Regards
> 
> # Rick
> 
> > From mmt Tue Dec 15 20:34:04 1992
> 
> To: Marken@courier4.aero.org  
> Subject: Re: Rick's proof: error not controlled  
> Cc: ./marken  
> Status: RO
> 
> Rick,
> 
> It's words again getting in the way...
> 
> Bill's model doesn't control the derivative of the squared error, in any  
> normal sense. That derivative has more the function of "error" in a  
> standard ECS, in that it determines the output of the reorganizing function.  
> That output is a reorganizing event that occurs from time to time in the  
> main hierarchy. The higher the value of the derivative of the squared  
> error, the more likely a reorganization even is to occur. I don't know  
> whether in Bill's simulations the rate was determinate or Poisson. Ours  
> is Poisson, which means that the probability of a reorganization event  
> happenning in a small delta-T is proportional to the value of the criterion  
> (derivative of squared error in Bill's case, unless he was using a  
> determinate time-interval between events).
> 
> Now what is controlling what? I think what is being controlled is the value  
> of some intrinsic variable. It has some error, and all this stuff about  
> derivatives and Poisson rates are attributes of the output function of  
> the control system for that intrinsic variable. As with any control system,  
> whether in the main hierarchy or in the reorganizing system, the actual  
> outputs are not controlled in themselves. Outputs are, shall we say, blind.  
> So the "criterion" is not controlling the Poisson rate. It is just a  
> component of the output function of a controller that controls an intrinsic  
> variable.
> 
> (Bill and I have an unresolved, and perhaps unresolvable, disagreement here  
> as to what might constitute an intrinsic variable, but that disagreement is  
> minor and not germane to this discussion.)
> 
> Martin
> 
> # PS. It feels great to be back on the air. I hope the link stays in action for a while.
> 
> > From Marken@courier4.aero.org Wed Dec 16 11:59:39 1992
> 
> Subject: Re: Rick's proof: error not controlled  
> To: @MVE.AERO.ORG:mmt@ben.dciem.dnd.ca  
> Status: RO
> 
> Martin
> 
> Let's put this on the Net.
> 
> > Bill's model doesn't control the derivative of the squared error, in any  
> > normal sense.
> 
> It does. I'll explain on the net.
> 
> > That derivative has more the function of "error" in a  
> > standard ECS
> 
> Because the intrinsic reference (for de^2) is 0.
> 
> > Now what is controlling what? I think what is being controlled is the value  
> > of some intrinsic variable.
> 
> de^2 is the intrinsic variable being controlled relative to an intrinsic  
> reference which happens to be 0; it could be something else (maybe  
> evolution wants the system to operate with de^2 at just a tad above  
> zero -- keeping you on your toes).
> 
> de^2 is controlled because it is both a cause and a result of reorganization;  
> and the sense of the feedback is (or should be) negative.
> 
> Regards
> 
> # Rick
> 
> > From mmt Wed Dec 16 14:10:23 1992
> 
> To: Marken@courier4.aero.org  
> Subject: Re: Rick's proof: error not controlled  
> Cc: ./marken  
> Status: RO
> 
> Rick,  
> I don't mind putting the discussion on the net, but I don't think it worthwhile.  
> There are too many long wavelength fish involved.
> 
> > Because the intrinsic reference (for de^2) is 0.
> > 
> > > Now what is controlling what? I think what is being controlled is the value  
> > > of some intrinsic variable.
> > 
> > de^2 is the intrinsic variable being controlled relative to an intrinsic  
> > reference which happens to be 0;
> 
> This makes no sense to me. In words, you are saying that whatever the  
> error is in the intrinsic variable (say blood CO2 level, for example),  
> what is controlled is that this error should not change. To me, the  
> only thing that makes sense is that there is some reference level for  
> blood CO2, and if this is too high or too low, and particularly if it  
> is moving in the wrong direction, then the main hierarchy needs reorganizing.  
> The reason for using the derivative of the squared error in the intrinsic  
> variable as part of the output function is that it is a short way of  
> ensuring that the error is both large and increasing, whichever sign it  
> has. Other functions having the same properties would also be useful.  
> But e\*de/dt is not a controlled variable, any more than (in fact less  
> than) is the error in a normal ECS.
> 
> Another way of seeing that d(e^^2)/dt is not controlled is to note that  
> zero is not a reference level for it. Negative values are even better,  
> becasue they show that the intrinsic variable is really being controlled.  
> A zero value is neutral in this respect, in that the error in the intrinsic  
> variable may be large but unvarying, or the error may be small while changing  
> wildly. Neither indicates good control, but both are compatible with good  
> control (momentarily).
> 
> If you want to put it on the net, collect all the postings and send them  
> out as one. But I don't think it worthwhile. I haven't seen anyone else  
> that seems to be interested in the matter (except presumably Bill, by  
> inference)
> 
> Martin

---

<div class="post-metadata">

**Author:** ![Marken\_Richard\_S1](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/m/977dab/32.png) [@Marken\_Richard\_S1](http://discourse.iapct.org/u/Marken_Richard_S1)\
**Post date:** [December 22, 1992, 6:18pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982/4 "1992-12-22T18:18:25Z")

</div>

Sent this last night but got no ACK from CSG-L and  
didn't see it on the net this morning -- pardon me  
if this shows up twice; I'm possibly still suffering  
from results of bad trip (well, the trip was fine,  
actually -- the mail waiting on my arrival left some-  
thing to be desired, however).

[From Rick Marken (921221 2000)]

Martin Taylor (921221 18:00)

Thanks for posting the correspondance; now I see what happened.

You said:

> I suppose I would agree that error could be controlled if it were to be  
> provided as input to the perceptual input function of a control system that  
> maintained the error at some reference level.

I replied:

> As you will see in a reply I plan to make to Greg, there is no  
> supposing necessary in this case. The error signal (which is now  
> a perceptual input to a control system) would DEFINITELY be  
> controlled.

You said:

> But what on earth would that  
> do other than enforce a situation in the ECS whose error was being  
> controlled  
> that would ordinarily arise only through unresolvable conflict. I can't  
> see why any hierarchy would include such a mechanism--but I suppose there  
> might be a reason somewhere.

In other words, you were rejecting the idea that perception of error  
in the control hierarchy should be the object of control by a reorganizing  
control system. But the notion that perceived level of error  
is an intrinsic variable controlled in a reorganization loop seems  
necessary to explain the many cases of learning where you develop new  
control skills even though you still can eat and breath. Dick Robertson  
did a nice experiment to show that reorganization can happen for no other  
reason than to solve a problem "better" than it's currently being solved;  
no obvious "intrinsic" variable is controlled except control skill (low  
level of error in the control system) itself.

So the discussion was about whether the reorganization model should  
be able to control the quality of control (measured as perceived  
level error in one or more control systems) -- and I think it should.  
But we seemed to have lost this thread and moved into a discussion of  
error and this is where I misinterpreted what you were talking about.  
You said:

> Actually, what Bill has done seems to be a little more complex. He has  
> found that the derivative of the squared error is a better criterion.

And I said:

> You mean, as the variable controlled by the reorganization system, right?

This was my mistake. When I saw your formula for error, (K1(e^^2)+K2(e\*  
de/dt), I assumed that this was the PERCEPTUAL FUNCTION,f, which transforms  
error in the hierarchical control systems (e) into the perception  
controlled by the reorganizing system, P, so that P = f(e). (I will  
adopt your convention of using capitol letters to denote variables in  
a reorganization loop -- small letters to denote the corresponding  
variables in a "regular" control system in the PCT hierarchy). In fact,  
your formula is for the OUTPUT function,g, that transforms the error in the  
reorganizing control system (E) into the reorganizing system output (O),  
so O = g(E). This fooled me because we rarely need to put non-linearities  
into the output functions of our models of tracking type data; just  
linear amplification. If we did add such non-linearities, they would  
be "absorbed" by the control loop (assuming that they are at least  
monotonic). But the output of the reorganizing system is not an amount;  
rather, like the tumbles of e.coli, the time between reorganizing events  
is the output that matters. So a non-linear output function might be just  
what the doctor ordered to make reorganization efficient; now I recall  
that THIS is what Bill discovered in his studies of reorganization  
algorithms that we talked about this summer.

So, Martin, I was not arguing that error is controlled (as you mis-  
takenly said in your summary of our exchange -- I'm quite sure,  
unintentionally; I don't think you tried to mislead); I just said that one  
intrinsic perceptual variable that might be controlled by a reorganizing  
system (which is itself a control system controlling perceptions relative  
to intrinsic references) is some measure of ambient error in the control  
hierarchy itself. So now we can get back to THAT conversation; do  
you think that reorganization involves control of perceived error in  
the hierarchy (in human control systems)? Why or why not? Can you think  
of a behavioral test for such a model? (These are serious questions-- I  
don't know the answers but I would appreciate hearing suggestions -- then  
maybe we could design some real experiments instead of just blabbering away).

As for Shannon and information theory; could you give me another sample  
of this "understanding" of PCT that you get with info theory that you  
don't get otherwise? Could it be that info theory is just one of those  
comfortable old pieces of wisdom (like reinforcement, statistics,  
reflexes, information processing, experimental methodology, decision  
theory. etc) that just MUST fit into this (PCT) SOMEWHERE? What if it  
doesn't?

Best regards

Rick

---

<div class="post-metadata">

**Author:** ![\_Martin\_Taylor](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/_/a9adbd/32.png) [@\_Martin\_Taylor](http://discourse.iapct.org/u/_Martin_Taylor)\
**Post date:** [December 23, 1992, 4:04pm UTC](http://discourse.iapct.org/t/rick-on-off-shannon/9982/5 "1992-12-23T16:04:12Z")

</div>

[Martin Taylor 921223 11:00]  
(Rick Marken 921221 2000) (delayed)

Rick,

I think the misunderstanding has been cleared up by your posting.

> So now we can get back to THAT conversation; do  
> you think that reorganization involves control of perceived error in  
> the hierarchy (in human control systems)?

Yes.

> Why or why not?

It seems a very plausible way that the linkages in the hierarchy can be  
connected with appropriate signs (and as I mentioned in a posting a few  
weeks ago, there seem to be 12 different ways that reorganization of this  
kind could be effected, so I'm not plumping for a mechanism).

> Can you think of a behavioral test for such a model?

Not offhand. And I think that a good part of this reorganising system  
is outside the individual, occurring on an evolutionary time-scale, so  
that aspect couldn't be demonstrated behaviourally.

> As for Shannon and information theory; could you give me another sample  
> of this "understanding" of PCT that you get with info theory that you  
> don't get otherwise? Could it be that info theory is just one of those  
> comfortable old pieces of wisdom (like reinforcement, statistics,  
> reflexes, information processing, experimental methodology, decision  
> theory. etc) that just MUST fit into this (PCT) SOMEWHERE? What if it  
> doesn't?

I admit the possibility, since we can never know when we are fooling ourselves.  
But see the postings to Tom and Bill yesterday. I hope that I will be able  
to satisfy you with what I plan to write in a more serious vein than  
impromptu net postings.

Happy Xmas.

Martin