[Bruce Nevin (991018.1125 EDT)]
Martin Taylor 991019 9:32
At 09:53 AM 10/18/1999 -0400, Martin Taylor wrote:
meaning of "side-effect". I use it only to indicate an effect of the
output of a control loop that does not influence the perception controlled
in that loop.
It follows that at lower levels there can be more side effects, at higher
levels, fewer.
Bruce Nevin
from [ Marc Abrams (991018.1301) ]
[Bruce Nevin (991018.1125 EDT)]
Martin Taylor 991019 9:32
>
>meaning of "side-effect". I use it only to indicate an effect of the
>output of a control loop that does not influence the perception
controlled
>in that loop.
It follows that at lower levels there can be more side effects, at higher
levels, fewer.
Yes. We often forget that there is a one to many relationship among
variables from the lower to higher levels in the hierarchy. A lower level
variable might very well be a part of any number of higher level control
processes. That's one of the reasons I think Chap 15 in B:CP is so
important. Martin pointed out how even a seemingly "simple" process can
become quite complex. We don't really understand how changes ( whether
intended or not ) at various levels are effected by changes in other levels
or other variables due to "side-effects".
Nice thread folks.
Marc
At 09:53 AM 10/18/1999 -0400, Martin Taylor wrote:
[From Bruce Abbott (991018.1245 EST)]
Martin Taylor 991018 1:05 --
What affects the perception of hunger is the ingestion of food. What
leads to the ingestion of food is the execution of some program as a
consequence of the output of the control system that set the reference
level for hunger to be low rather than high. That higher-level system has
succeeded in controlling its perception by means that have developed
over time by reorganization. So long as its perception is near its
reference, those acts need not take place. But one buys things at the
market when one is _not_ hungry, and one prepares the oven before
it is time to eat. These acts are _not_ acts to correct an error in
the perception of level of hunger higher than the reference value. They
are acts to correct an error in a higher level system with a longer
time-frame.
I agree that sometimes I purchase food and light the stove for reasons other
than hunger, or in addition to hunger, but that is beside the point I am
pushing here. That point is that I may do these things precisely because I
_am_ hungry and would like to do something about it. Tell me how, in HPCT,
the assertion of a hunger perception orchestrates a chain of events
(purchasing food, lighting oven, cooking food, consuming food) that
culminates in the elimination of my hunger. I am assuming that I
consciously and deliberately do these things in order to bring my hunger
level back to its reference level of zero. It involves organizing a whole
chain of control processes, operating at a high level in the hierarchy, to
bring this result about.
I would say that I can use control of high-level perceptions as the means of
controlling a low-level perception, hunger. In the system diagram, these
high-level systems would be found in the output function of the hunger
control system. Do you disagree?
Regards,
Bruce
[From Bruce Gregory (991018.1424 EDT)]
Bruce Abbott (991018.1245 EST)
Tell me how, in HPCT,
the assertion of a hunger perception orchestrates a chain of events
(purchasing food, lighting oven, cooking food, consuming food) that
culminates in the elimination of my hunger. I am assuming that I
consciously and deliberately do these things in order to
bring my hunger
level back to its reference level of zero. It involves
organizing a whole
chain of control processes, operating at a high level in the
hierarchy, to
bring this result about.
The process is similar to one in which the assertion of a lack-of-opera
perception orchestrates a chain of events (driving to the ticket window,
purchasing a ticket, entering the lobby, finding your seat) that
culminates in the elimination of the pangs associated with a
lack-of-opera perception. The lack-of-opera perception apparently
organizes a whole chain of control processes, operating at a high level
in the hierarchy to bring about this result. It's a linear chain of
causality of the sort we are all familiar with. (Mild irony)
Bruce Gregory
from [ Marc Abrams (991018.1509) ]
[From Bruce Abbott (991018.1245 EST)]
I agree that sometimes I purchase food and light the stove for reasons
other
than hunger, or in addition to hunger, but that is beside the point I am
pushing here.
Yes, but I don't think it's besides Martin's point.
That point is that I may do these things precisely because I
_am_ hungry and would like to do something about it.
True, but as Martin has pointed out. it may very well have nothing to do
with hunger per se. In oreder to know which is the case you would have to
know not only what someone might be controlling for but you would have to
know the state of all ( i.e. related ) lower level variables at a _specific_
point in time. Tricky stuff. 
Tell me how, in HPCT,
the assertion of a hunger perception orchestrates a chain of events
(purchasing food, lighting oven, cooking food, consuming food) that
culminates in the elimination of my hunger.
What I get from Martin's argument ( and I agree with, if I am accurate )
is that "hunger" might be caused by the chain of events you describe and
then again "hunger" may be a vestige ( side effect )of some other
controlling process.
I am assuming that I
consciously and deliberately do these things in order to bring my hunger
level back to its reference level of zero.
Given those assumptions you _may_ be correct. But then again you may not.
Again, in order to get an answer you would not only need to know what
variable_s_ the person is controlling for but you would also need to know
which lower level variables are being sharedand what effects those might
have on the controlling process.
It involves organizing a whole chain of control processes, operating at a
high level in the hierarchy, to bring this result about.
It involves _multiple_ interconnecting chains of signal processing ( some of
which is control, some not ) to control the _simpleist_ of tasks. _Nothing_
is as easy and simple as it seems. _Nothing_ :-).
I would say that I can use control of high-level perceptions as the means
of
controlling a low-level perception, hunger. In the system diagram, these
high-level systems would be found in the output function of the hunger
control system. Do you disagree?
I'll be interested in Martin's response. You certainly could be right. But I
don't think that "hunger" _always_ follows from a "higher level" controlling
of a lower level perception named "hunger".
Marc
[From Tim Carey (991019.0735)]
Perhaps it's a "Down Under" thing but I can't ever remember eating because I
was hungry and none of my friends can either. In fact, I would probably go
so far as to suggest that the majority of people in the Western world don't
eat when they are hungry.
For me, eating has much more to do with things like the time of day (it's
time for breakfast), or the people I'm with (let's grab something to eat)
than any perception of physiological states.
Do people know what others are talking about when they talk about "hunger"
('cause I'm not sure I do)
Cheers,
Tim
[From Bruce Abbott (991018.1640 EST)]
Bruce Gregory (991018.1424 EDT) --
Bruce Abbott (991018.1245 EST)
Tell me how, in HPCT,
the assertion of a hunger perception orchestrates a chain of events
(purchasing food, lighting oven, cooking food, consuming food) that
culminates in the elimination of my hunger. I am assuming that I
consciously and deliberately do these things in order to bring my hunger
level back to its reference level of zero. It involves
organizing a whole chain of control processes, operating at a high level
in the hierarchy, to bring this result about.
The process is similar to one in which the assertion of a lack-of-opera
perception orchestrates a chain of events (driving to the ticket window,
purchasing a ticket, entering the lobby, finding your seat) that
culminates in the elimination of the pangs associated with a
lack-of-opera perception.
I agree that the two cases are isomorphic.
The lack-of-opera perception apparently
organizes a whole chain of control processes, operating at a high level
in the hierarchy to bring about this result.
How? (HPCT explanation only, please.)
It's a linear chain of
causality of the sort we are all familiar with. (Mild irony)
We may all be familiar with it, but as far as I can tell, it ain't HPCT.
HPCT would state that I have a reference for a sequence and act to produce
that sequence of perceptions. It doesn't say that I'm going to carry out
that sequence in order to control a variable lower in the hierarchy, it says
that I am going to set a reference for lower level CVs in order to bring
about a sequence of perceptions. I am cooking and then eating in order to
complete a sequence of those perceptions, not because I'm hungry. It's
possible that this might be true on some occasions, but my feeling is that
on most occasions, I do all these things because I'm hungry, not because I
have decided to carry out a sequence of acts.
Mind you, I understand that you are assuming that reorganization occurs
because there is some intrinsic variable not being satisfied until I carry
out that sequence, and that this reorganization creates the sequence-level
system. I believe that this is what Martin means when he says that
satisfying hunger is a "side-effect" -- reorganization continues until some
sequence results that brings the error in some intrinsic variable correlated
with hunger near zero. But then, what raises the reference for the
sequence-level perceptual system, so that I perform this sequence when
hungry? HPCT would say that this would be done by the output of a system at
the next level up, not by error in the intrinsic variable itself or its
surrogate (hunger).
Bruce A.
[From Bruce Abbott (991018.1700 EST)]
Tim Carey (991019.0735) --
(Wow, it's tomorrow already at your place! I'm talking to someone in the
Future!)
Perhaps it's a "Down Under" thing but I can't ever remember eating because I
was hungry and none of my friends can either. In fact, I would probably go
so far as to suggest that the majority of people in the Western world don't
eat when they are hungry.
Wow. You have some _strange_ friends, there in the future.
For me, eating has much more to do with things like the time of day (it's
time for breakfast), or the people I'm with (let's grab something to eat)
than any perception of physiological states.
Do people know what others are talking about when they talk about "hunger"
('cause I'm not sure I do)
Are you saying that you are not more likely to eat when "hungry" than when
not "hungry"? If so, then your system works differently than mine.
Keep in mind, the demonstration that you eat for reasons other than hunger
is no proof that you do not also sometimes eat _because_ you are hungry.
Another observation -- although it may seem to, your comment has no bearing
on my argument, which presupposes that our hypothetical person (me) is
motivated to terminate his perception of hunger. He, at least, eats because
he is hungry. But the motive really isn't important to the argument.
Bruce A.
[From Bob Christensen (9910181300 PT)
I want to restate my original purposes in my original post about
understanding the hierarchy. I was trying to understand how it is that some
low level mismatch like with hunger could lead to higher level control
systems like progams being engaged toward its end. I was not arguing that
all variables that allow one to control hunger are controlled in the presence
of hunger. I was trying to understand this problem which was confusing to me
for a long time, and I sensed that it was likely confusing to others as well
who talk as if everything we do is to serve the highest reference
perceptions. If this is an area of common confusion, it makes sense to be
quite aware of it so that we can explain PCT to newcomers in a manner that
coheres with their experience better. I was also not arguing that one could
not choose different references for tolerating hunger according to higher
level goals like being a martyr or wanting to loose weight. I was also not
arguing that hunger occurs as part of the perceptions in all of the loops
that are the means by which we satify hunger (the whole side-effects thing).
I was trying to follow good scientific procedure in finding a case which I
could not seem to account for with the current theory, making the case as
simple as possible, and trying to see how the current theory handles the case
or if the theory needs revision.
I don't think that anything that I have said contradicts the model, but I
think some of the explanation is different as follows.
1. I think that signals like hunger are inputs to low levels of the
hierarchy (intensities and sensations), and that they covary with intrinsic
error signals (maybe not perfectly but roughly).
2. I think that these signals greatly simplify the job of reorganization.
3. More generally, I think that perceptions that represent errors at lower
levels are availible to higher levels. Anytime I think of a difference
between where I am and where I want to be, it is analogous to an error.
Martin says, Hunger can be controlled at different levels according to higher
purposes. He also says that when hunger is greater than the reference, this
turns on a system at the highest level which employs other lower level
systems (which do not include hunger as part of their perceptions) that have
the "side-effect" of reducing hunger.
4. What I find curious is how this hunger mismatch gets to the highest level.
I think of hunger as intensities and sensations. How is it that a mismatch
at this level effects turning on a larger loop that includes programs. I can
think of two ways that this can happen. The mismatch is incorperated into
higher level perceptions about what hunger means (this may include cross
level relationships) and is the essential ingredient of the high level
mismatch. Second, programs can take as inputs (to be tested at branch
points) perceptions directly from any of the eight lower levels. In this
case, one checks ones low level hunger perceptions and if it's greater than a
certain value you branch to food aquiring programs. A combination of these
two processes may be more the case.
5. I don't think that it makes sense to say that lower order references are
always to reduce higher level references.
I have not come across most of the above five points anywhere in the PCT
literature (I have heard them mentioned here and there), and I think they are
important to understanding the hierarchy. Do people agree or disagree with
them.
Bob C.
[From Rick Marken (991017.1510)]
Bruce Abbott (991018.1245 EST) --
Tell me how, in HPCT, the assertion of a hunger perception
orchestrates a chain of events (purchasing food, lighting oven,
cooking food, consuming food) that culminates in the elimination
of my hunger.
Leaving aside the question of whether hunger "asserts" anything,
I think you can get an idea of how hunger control works in
HPCT by looking at the operation of Bill's artificial cerebellum
model. In that model, a parameter (specifically, the output
transfer function) of a set of kinesthetic control systems is
"tuned up" as the means of controlling an intrinsic variable
(the error signal driving the outputs in each of the kinesthetic
control systems). The intrinsic controlled variable (the
controlled error variable) is analogous to the variable we
experience as hunger; adjustment of the parameters of the
kinesthetic control systems is analogous to changing the
parameters of control systems in the hierarchy in order to
keep hunger under control.
Under normal circumstances, we are controlling perceptions
in a way that keeps the intrinsic hunger variable -- let's
say it's blood sugar level -- under control; we eat regular
meals and grab snacks occasionally. As blood sugar starts
to deviate from it's intrinsic reference level (which, I
presume, is what you mean by hunger "asserting itself") the
rate of reorganization increases; parameters of control
systems in the hierarchy are varied (as in the artificial
cerebellum example) _as the means_ of keeping the intrinsic
variable (blood sugar) under control. The rate of reorganization
slows down again once the parameters of the control systems
in the hierarchy are allowing good control of variables that,
when controlled properly (such as control of hunting, butchering
and eating) that keep the intrinsic variable under control.
Best
Rick
--
Richard S. Marken Phone or Fax: 310 474-0313
Life Learning Associates mailto: rmarken@earthlink.net
http://home.earthlink.net/~rmarken
[Martin Taylor 991019 0:41]
[From Bruce Gregory (991018.1022 EDT)]
Martin Taylor 991019 9:32
And _therefore_ hunger reduction is one possible side-effect of paying
the cashier. There are many other side-effects of this same action,
including a perception of having less money in the wallet, perceiving
the cashier saying "thank you," perceiving weight on the arms shortly
thereafter... None of these enter into the control loop for perceiving
myself to be paying the cashier.Here's my problem. I do not pay the cashier in order to have less money
in my pocket, which I agree is a side-effect. Nor do I pay the cashier
in order for her to say thank you (although I may expect her to do so),
this too I agree is a side-effect. I do not pay the cashier to feel a
weight in my arms--I'm perfectly happy for someone else to carry the
groceries to the car. I do pay the cashier as part of a plan called
"doing the weekly grocery shopping." This is an intended outcome.
Calling it a side-effect seems misleading to me.
Calling what a side-effect? And a side-effect of what?
You seem to use it [side-effect] the mean an effect that does
not influence
_any_ perception controlled within the same hierarchy. I
don't think your
usage is technically well-defined.No, I use it to mean that which is not part of the intended outcome.
Of what?
I
think I understand your usage but I find it unilluminating. Killing you
is, if I understand you properly, a side-effect of pulling the trigger
on my pistol. I tend to think of pulling the trigger as part of the plan
to achieve the outcome of killing you.
Killing me _is_ a side-effect of the action of the control system for
which the perception is the trigger pull. It is _not_ a side-effect
of the system for which the controlled perception is my state of life.
The trigger-pull control system is part of the loop of the "state-of-
life-perceiving control system, for which the reference level is me dead.
You are still confusing a whole-organism "intended result" with the
"intended results" of single control units.
Martin
[Martin Taylor 9910 19 0:52]
[Bruce Nevin (991018.1125 EDT)]
Martin Taylor 991019 9:32
meaning of "side-effect". I use it only to indicate an effect of the
output of a control loop that does not influence the perception controlled
in that loop.It follows that at lower levels there can be more side effects, at higher
levels, fewer.
Could you push the argument for this a little bit, please? I don't
follow the logic that leads to it.
Martin
At 09:53 AM 10/18/1999 -0400, Martin Taylor wrote:
[Martin Taylor 991019 1:25]
[From Bruce Abbott (991018.1640 EST)]
to
Bruce Gregory (991018.1424 EDT) --
Mind you, I understand that you are assuming that reorganization occurs
because there is some intrinsic variable not being satisfied until I carry
out that sequence, and that this reorganization creates the sequence-level
system. I believe that this is what Martin means when he says that
satisfying hunger is a "side-effect" -- reorganization continues until some
sequence results that brings the error in some intrinsic variable correlated
with hunger near zero.
That's nothing like what I mean. Reorganization doesn't come into it,
except that it is by reorganization that the system learned which
side-effects turn out to be useful in allowing the high-level control
system that wants the hunger perception to be "low" to control its
perception.
I don't know why you bring reorganization into your comments of what
Bruce Gregory was saying, either. I don't remember him bringing it up.
---------------
By the way, I thought the _perception_ of hunger was related to stomach
emptiness, not blood sugar or other intrinsic variables. Am I wrong
there?
Martin
[From Bruce Gregory (991019,0653 EDT)]
Martin Taylor 991019 0:41
Killing me _is_ a side-effect of the action of the control system for
which the perception is the trigger pull. It is _not_ a side-effect
of the system for which the controlled perception is my state of life.
The trigger-pull control system is part of the loop of the "state-of-
life-perceiving control system, for which the reference level is me dead.You are still confusing a whole-organism "intended result" with the
"intended results" of single control units.
Not any more. Thanks for the clarification, Martin.
Bruce Gregory
[From Bill Powers (991019.0747 MDT)]
Bruce Abbott (991017.1625 EST)--
Martin, I'm afraid that I have to side with Bob Christensen (991016.1702 PT)
on this one. The scenario you present is possible, but unlikely to be
anything like the typical situation, in which systems fairly high in the
hierarchy (e.g., program level) actually become the _means_ by which a
low-level perception is controlled. Reduction in hunger is not a
side-effect of the actions that eventually bring food to mouth, it is in
many cases the _intended consequence_ of these acts, taken as a whole.
I'll still side with Martin's excellent post, although I think
Bob Christensen has brought up many important points we need to think
about. With regard to Bob's post, all that he suggests is possible, but
when you try to model it it gets extremely complicated. I feel constrained
by my own principles to put most of those problems aside until I can see
some way to test any answers I might think up.
The levels in HPCT are not complete people; it's a mistake to treat them as
if they were alike in any way beside the basic function of controlling. A
relationship system, for example, controls strictly in terms of
relationships between perceptual signals; it knows nothing of sensations
(like hunger) or logical consequences (like starving to death). It's quite
possible that when hunger exists, what some systems do in the attempt to
make it go away acts as a disturbance on other system, which then deal with
that disturbance by doing the things (i.e., causing perceptions to occur)
that higher systems have learned to do when disturbed. It could be that
without the higher systems to categorize and reason about certain
sensations, those sensations would have no meanings to the organism. After
all, hunger can't possibly be controlled at the level of sensations. Only
when perceived as part of a higher level world is it appreciated as
something to be avoided, and possibly something dangerous (or as Martin
reminded us, something to be sought for moral or other reasons). The reason
hunger can't be controlled at the lowest levels ( in an adult) that that in
order to control it, the organism has to control at least relationships
with other objects that can be eaten.
We shouldn't assume that just because a certain type of experience involves
sensations or other low-level perceptions, it is controlled because of its
meaning at those levels. Most of us eat in a very ritualized, stylized, and
perfunctory way, never actually letting hunger become anything more severe
than a slight twinge. Control systems of quite high levels are involved,
dealing with hunger signals just as signals, not as indicators of something
wrong, and indeed behaving in such a way as to keep the hunger signals from
ever becoming significant. We think, "I'd better grab a sandwich now, there
isn't going to be time for lunch before the meeting." So we keep the beast
happy, and it doesn't disturb us when we're busy with more important things.
Best,
Bill P.
How can this fact be harmonized with the hierarchical control structure
proposed in HPCT?Regards,
Bruce
[From Bill Powers (991019.0812 MDT)]
Bruce Abbott (991017.2105 EST)--
Bruce Gregory (991017.1830 EDT)]
Here is the model I use. The hierarchy exists to control hunger (and other
intrinsic variables). Hunger is not a controlled variable. Hunger is not
part of the hierarchy. Most of the actions taken by the hierarchy to control
hunger happen in the absence of hunger.
Abbott:
Hmmm. Hunger is not a controlled variable, but the hierarchy exists to
control hunger, which is not controlled. I must be misunderstanding you.
Please clarify. It sounds to me like you are reverting to Martin's "side
effect" explanation. I don't buy that. I think that when I'm hungry, I
might very well light up the oven for the ultimate purpose of satisfying my
hunger.
One problem here is that while all perceptions begin at the intensity
level, not all are controlled at that level. Hunger is an example: there is
nothing that an intensity-control system can do to affect hunger signals
(in an adult). So there are no hunger-control systems at the lowest level.
Hunger may be sensed as an intensity, then as a sensation, then as a
configuration, and so on, but until a level is reached that can vary
actions in a way that might affect hunger (such as putting something in the
mouth) can hunger be thought of as a controlled variable.
Another thing to keep in mind is that hunger-the-intensity is not the same
as hunger-the-intrinsic-error-signal, although the two signals probably
occur under related circumstances. The physical state of being low on
nutrients (or the consequences thereof) becomes an experience only
indirectly. We do not sense (neurally) circulating glucose; most of what we
sense comes from low-level processes affected by low glucose. There might
be pains in the stomach, or gurgling we can feel and hear, and so on -- but
I doubt that we are born understanding the connection between those
sensations and the fact of not having eaten for a while. "Hunger" is not a
specific biochemical variable; it's an experiential construct related to,
but not identical to, physiological states.
As I think of the reorganizing system, its operation is entirely
independent of the hierarchy that it affects. What the reorganizing system
senses is not the same as what the hierarchy senses -- it's more
biochemical, not neural. The same circumstances that give rise to intrinsic
error signals might well also give rise to recognizeable perceptions, which
would be helpful for purposes of building relevant control systems, but the
two classes of "perception" are not the same.
Best,
Bill P.
[From Bill Powers (991019.0836 MDT)]
Martin Taylor 991018 1:05 --
Martin, I like your line of argument about hunger control. We have to be
careful, of course, not to make up premises just to keep the hierarchy the
way it is, but on the other hand if it is possible to handle valid
objections without changing the basic model and without ad-hoc premises, we
should try very hard to do so before making changes. I've worried about
apparent inversions of hierarchical order, but so far have always been able
to find a reasonable explanation that requires no inversion. And naturally,
I've been suspicious of my own success, considering my investment in the
model.
It's good to see others arguing about these things.
Best,
Bill P.
I think maybe Bruce Gregory understood my post, but it seems neither
Bruce Abbott nor Bob Christensen did. But perhaps even Bruce Gregory
did not. I'll try again.[From Bruce Abbott (991017.2105 EST)]
Bruce Gregory (991017.1757 EDT) --
I agree that Martin's choice of the term "side-effect" was unfortunate.
I disagree--see the end of this message.
Each
of the steps he describes are intended outcomes in a sequence intended to
reduce hunger. The test would show this. No need to harmonize this with
anything, it's orthodox HPCT.My point was that the steps taken have the _effect_ of reducing hunger,
but they are part of a control loop at a higher level. That higher-level
control loop has a perceptual signal influenced by the perceived level
of hunger, and it has a reference value for its perception that cannot
be satisfied unless the perceived level of hunger is low. The acts, such
as paying a supermarket cashier or turning the control knob on the oven
do not include the value of the hunger perception in their perceptual
signals, nor do they directly affect the level of hunger.What affects the perception of hunger is the ingestion of food. What
leads to the ingestion of food is the execution of some program as a
consequence of the output of the control system that set the reference
level for hunger to be low rather than high. That higher-level system has
succeeded in controlling its perception by means that have developed
over time by reorganization. So long as its perception is near its
reference, those acts need not take place. But one buys things at the
market when one is _not_ hungry, and one prepares the oven before
it is time to eat. These acts are _not_ acts to correct an error in
the perception of level of hunger higher than the reference value. They
are acts to correct an error in a higher level system with a longer
time-frame.In orthodox HPCT, higher-level control systems set the references of
lower-level control systems as the means by which the higher-level systems
control their CVs.But in the situation we are discussing, an intensity-level (hunger) control
system sets the references of various program- or sequence-level control
systems as the intensity-level system's means of controlling its CV (hunger
level). That's _also_ orthodox HPCT? How so?That's not orthodox HPCT, and I hope my discussion above argues that it
probably doesn't happen, either.Bruce Gregory (991017.1830 EDT)]
Here is the model I use. The hierarchy exists to control hunger (and other
intrinsic variables). Hunger is not a controlled variable. Hunger is not
part of the hierarchy. Most of the actions taken by the hierarchy to control
hunger happen in the absence of hunger.The last sentence is true, but that doesn't mean that the level of
perceived hunger is uncontrolled. There is certainly a difference between
the reference level for hunger under everyday cirumstances, under
circumstances when one is trying to conserve a limited food supply on
a trek, and in the circumstance that one is trying to perceive oneself as
a martyr. And if there are differences in reference levels, it is likely
that the perception is a controlled one, especially if one's actions
differ for a given level of perceived hunger under the three different
sets of circumstances.It sounds to me like you are reverting to Martin's "side
effect" explanation. I don't buy that. I think that when I'm hungry, I
might very well light up the oven for the ultimate purpose of satisfying my
hunger.Yes, you very well might. But you wouldn't even be trying to "satisfy"
your hunger if that satisfaction did not satisfy some higher-level
controlled perception, would it now? We aren't in an S-R situation where
perception of hunger MUST lead to immediate eating if food is available.
Imagine getting hungry during an important meeting! What would the boss
say if you just left to get a snack?--------------------
I think you have missed the critical importance of side-effects in the
operation of the hierarchy generally. The whole reorganization system
depends on it--almost all controlled perceptions having no direct
physical connection with the intrinsic variables, and the intrinsic
variables not entering into the value of the controlled perception.
One sustains one's blood sugar by getting along with the neighbours, by
pleasing the boss, by using an umbrella in the rain, by voting for a good
party, etc. etc.The end result is that one is able to eat when blood sugar is low and
one feels hungry--if one wants to do so. But it's an awfully long stretch
to argue that controlling one's perception of "boss pleased" or "feel dry"
is part of the output of a hunger-control system.The world _is_ moderately consistent in its operation, and many higher
level control systems work by getting lower-level control systems to act
(i.e. by setting reference levels for low-level controlled perceptions)
in such a way that the side-effect of their control influences different
low-level perceptions. In our constrained world, such side-effects can
hardly be avoided. In a randomly organized set of control systems, they
are almost certainly unhelpful.But we are not randomly organized--we are _reorganized_.
Reorganization keeps what works, and allows what doesn't to fade
away and change. So the small proportion of helpful and consistent
side effects is kept (according to orthodox HPCT reorganization theory).
It takes a bit of convoluted thinking to avoid this happening while
sticking to HPCT when there are many parallel control units active at
any level of the hierarchy.So I reject Bruce Gregory's statement that my choice of the term
"side-effect" was unfortunate. It was deliberate and it was accurate.
But the side-effect was not of the control system that "desired" hunger
to be low. It is of the intermediate control systems that do not include
the perception of hunger-level as part of their perceptual input function,
but that nevertheless have the effect of enabling hunger-reduction.
Hunger reduction is a direct effect of the act of eating, and the control
loop for hunger-level is in the direct line of some other high-level
system.------------------
I hope all this isn't too incoherent. I should have gone to bed before
starting it!Martin
[Bruce Nevin (991019.1042 EDT)]
Martin Taylor 9910 19 0:52 --
[Bruce Nevin (991018.1125 EDT)]
Martin Taylor 991019 9:32
meaning of "side-effect". I use it only to indicate an effect
of the output of a control loop that does not influence the
perception controlled in that loop.It follows that at lower levels there can be more side effects,
at higher levels, fewer.Could you push the argument for this a little bit, please? I
don't follow the logic that leads to it.
A loop controlling a tactile pressure intensity perception could possibly
have many side effects if a finger is pushing a button or a key on a
keyboard, but this is exceptional. A loop controlling a program "resupply
the kitchen with groceries" accumulates all the side effects of all the
lower-level loops that it uses as means.
A higher-level loop includes many lower-level loops as part of the entire
loop through the environment. Of course, you could argue that the
"environment" of a program-level loop is a universe of sequence or
relationship perceptions (there was some debate about the relative order of
these). If you push your distinction of single loop vs. whole organism that
far, I am not sure how you would specify what is a side effect. (I think
that would push the distinction too far -- a single loop out through lower
levels and through the environment is not the whole organism.)
Bruce Nevin
At 12:53 AM 10/19/1999 -0400, Martin Taylor wrote:
At 09:53 AM 10/18/1999 -0400, Martin Taylor wrote:
[From Bill Powers (991019.0841 MDT)]
Bob Christensen (991017.2144 PT)--
I did not hypothesize that lower level control systems set the references for
higher level systems. I hypothesized that lower level errors (or analogues
there of) are incorporated into higher level perceptions starting from the
lowest levels.
But hunger signals are not error signals; they're perceptual signals. You
don't have an error signal until a perceptual signal is compared with a
reference signal. "Hunger" is a name we learn to give to a particular
constellation of sensations from inside us. We learn to control these
sensations at a low level because until we do, we keep reorganizing every
time our nutrient level gets too low -- low enough to interest the
reorganizing system.
I think there is some confusion in these conversations between hunger as an
_objective physiological state_ and hunger as our perception of the effects
of being in that state. We are born with built-in reference signals --
intrinsic reference signals -- for a particular state of nutrition, as
representing by substances in the blood stream and who knows what else. But
we are not born knowing the significance of all neurally-represented
sensations that may arise from our bodies. Read Martin's exposition on
side-effects carefully. This is what he is talking about.
Best,
Bill P.
These error analogue inputs to higher levels are instrumental
in organizing the higher level systems because one can relate them to other
perceptions which often occur with them. In this way one can come to better
understand how the error analogue inputs arise and how one might cease them.
Once the higher level systems are organized the error analogue inputs, when
present, result in errors at the higher levels in comparison to references
that are already set. Then, the error signals at this high level drive
outputs. The net effect can be that when the error analogue inputs are
present they do affect the references set at higher levels because they
result in the error at the highest level (which may be a few levels up) that
changes references at all lower levels (often along branches commonly thought
of as the voluntary nervous system).If this scenario is correct, I think that it means that it does not make
sense to say that lower order references are always to satisfy higher order
references, or that lower references are always the means to satisfying
higher order references. It's just not necessarily the case. There are
probably often times that one wants an event to occur, but in order to make
it occur one has to see many higher level relationships, and employ a
program. The program ceases when the event occurs, not when some higher
level principle is satisfied. The principle is used to organize the program
to begin with, probably when one was frustrated, and probably when error
analogue inputs from the event level were present.Bruce Abbott
I think that when I'm hungry, I
might very well light up the oven for the ultimate purpose of satisfying my
hunger.I concur.
[Mark Lazare (101799)]
If I may take a shot at this -- Hunger is not a conrolled variable -- no
more
that anxiety or depression is a controlled varaible. Hunger is a emotion or
feeling that is an error signal. Hunger is an error signal telling you, your
system is crashing you need fuel, some carbon based matter. Engery is your
controlled Varrable not the hunger -- Hunger and the lack thereof will let
you know if you need to eat or not.Hunger is a variable because it can range from no hunger (satiation) to
extreme hunger. Hunger is controlled via eating usually near the reference
for no hunger. Hunger is a controlled variable. Hunger is perceived and it
is an error in the sense that it is correlated with low "fuel" in the blood.
That's why I called it an intrinsic error analog input to the hierarchy.
Energy is a high level concept. Animals do not have the concept of energy or
models of glucose floating in their blood stream. They feel the
uncomfortable low level perception of hunger and they act to reduce it
through their species specific routines. Emotions are perceptions and
representations of errors as well. But emotions are different from hunger in
this way. Emotions often result when ones hierarchical references are
frustrated or disturbed. Frustrated when stuck in traffic, worried about
performance on tomorrow's presentation. Hunger simply arises through some
mechanism that reflects as you say, low "fuel" in the blood.The main point of my original post was that higher level references can serve
to change a lower level perception like hunger to a desired state.Mark Lazare (101799)]
MOL for Disturbing Views---
The Hows and Whys, related to heirarchies. In the MOL, if you want to find
out a motive, goal, desire, proposes, or intention, you ask the question;
WHY?.Okay.
This is going up a level.
I don't think this is necessarily the case. Comments like this are one of
the reasons I made my original post.If you what to find and appropriate output, you as HOW?
Okay
This will take you down a level.
I don't think this is necessarily the case either.
Where is the Reference coming from at the highest level in the hierarchy?
Any conjectures anyone?Maybe it is not originating from the highest level.
Bob C.
[From Bruce Gregory (991019.1052 EDT)]
Bruce Abbott (991018.1640 EST)
>The lack-of-opera perception apparently
>organizes a whole chain of control processes, operating at a
high level
>in the hierarchy to bring about this result.How? (HPCT explanation only, please.)
I doubt there is a lack-of-opera perception. There are certainly a
higher order perceptions including the memory of operas we enjoyed.
Learning that Cosi Fan Tutti will be performed next week-end may lead us
to recall enjoyable experiences in the past. Depending on the other
intentions we have, and their urgency, we may carry out a series of
steps that will bring us to the theatre at the appropriate time.
>It's a linear chain of
>causality of the sort we are all familiar with. (Mild irony)We may all be familiar with it, but as far as I can tell, it
ain't HPCT.
Excellent!
HPCT would state that I have a reference for a sequence and
act to produce
that sequence of perceptions. It doesn't say that I'm going
to carry out
that sequence in order to control a variable lower in the
hierarchy, it says
that I am going to set a reference for lower level CVs in
order to bring
about a sequence of perceptions.
Quite so.
I am cooking and then
eating in order to
complete a sequence of those perceptions, not because I'm
hungry. It's
possible that this might be true on some occasions, but my
feeling is that
on most occasions, I do all these things because I'm hungry,
not because I
have decided to carry out a sequence of acts.
The problem is the word "because". You do these things because you have
learned that they among many other possible sequences (including driving
up to the window at McDonald's) keep intrinsic error at a minimal level.
The particular sequence you choose to control depends on such things as
whether you are trying to impress your boss or are in a rush to attend
the opera.
Mind you, I understand that you are assuming that
reorganization occurs
because there is some intrinsic variable not being satisfied
until I carry
out that sequence, and that this reorganization creates the
sequence-level
system. I believe that this is what Martin means when he says that
satisfying hunger is a "side-effect" -- reorganization
continues until some
sequence results that brings the error in some intrinsic
variable correlated
with hunger near zero.
I agree with Martin. Neither of us are talking about reorganization.
But then, what raises the reference for the
sequence-level perceptual system, so that I perform this sequence when
hungry? HPCT would say that this would be done by the output
of a system at
the next level up, not by error in the intrinsic variable
itself or its
surrogate (hunger).
Indeed. You have built a hierarchy to maintain intrinsic error at low
levels, but the intrinsic variables do not serve as input to the
hierarchy, at least in the HPCT model. Reference levels at the top of
any hierarchy were probably established some time ago by reorganization.
Bruce Gregory