[From Rick Marken (961017.1500)]
Martin Taylor (961017 14:50) --
Kepler did not provide a mechanism; I did, in some detail, repeated on
several occasions over the years, and Rick knows it. The mechanism is a
consequence of reorganization in interacting control systems.
Reorganization IS a mechanism; it is the mechanism that controls the quality
of controlling done by control systems. Reorganization is a control
mechanism. Do you propose another mechanism -- one that "is a consequence of
reorganization" -- to explain the behavior of interacting control systems?
If so, that's great.
I was critical of your approach to theory because it seemed to me that you
were using what you said was an _analytical tool_ ("attractor theory") as a
_mechanism_ to explain aspects of social interaction. For example, in an
earlier post you said:
Attractor theory, if you want to call it that (I prefer "dynamics") argues
that these three are the only possibilities for interacting systems.
It sounded like you were making a prediction about a possible observation
(what might be observed in interacting systems) based on a method of
describing (attractor theory) those observations. It sounded to me like you
were saying something as peculiar as "Laplace theory argues that there are
only three possibilities for the shape of the orbit of Mars". Of course,
Laplace "theory" could describe the orbit but you'd need Newton's theory too
I don't understand how attractor theory can "argue" or predict anything.
Reorganization theory does predict behavior (such as the behavior of subjects
in the "E. coli" experiment). This behavior can be _described_ (possibly in
very interesting and suggestive ways) by attractor (or Laplace) theory; but
it certainly can't be predicted by those theories.
You seem to have difficulty making it clear (to me, anyway) that the
"theories" you like (attractor, information, etc.) are analytic devices (like
algebra and calculus) rather than theoretical mechanisms. I'd be interested
in hearing whether anyone else has this problem with your posts. Maybe it's
you have to be able to perceive that a particular configuration is a
refrigerator rather than a stove or window.
Bill Benzon (961017) --
And just how do you do that? ...How do we recognize it?
That is a question of how the perceptual functions work. I presume perceptual
functions work pretty much the way Bill Powers said they work in B:CP.
Physical signals are converted by sensory receptors into intensity
perceptions; intensity perceptions are converted by first order perceptual
functions into sensation perceptions; sensation and intensity perceptions are
converted by second order perceptual functions into configuration
perceptions, etc. Near the top of this hierarchy, category level perceptual
functions are converting lower level perceptions into classes like perceptual
signals indicating the degree to which the input is in the class
"refrigerator", "stove", etc.
I don't have any idea how the perceptual functions actually work; I presume
that the perceptual functions themselves are neural networks that take lower
level perceptual signals as inputs and produce a single perceptual signal as
an output. The magnitude of this output signal represents the degree to which
a particular perceptual variables is represented in the states of the input
perceptual signals. If the perceptual function computes "refrigerator", the
magnituide of the output indicates the degree to which the input signals are
I'm standing still, not moving. I'm looking right at the refrigerator.
What motoric force am I exerting on that refrigerator?
None. Which just means you ain't gonna get the door open;-)
there is experimental evidence that we can recognize many things with a
single glance. Where is the motoric output in single-glance recognition?
You don't need motoric output to _perceive_. You need motoric output to
_control_. We can obviously perceive without controlling. (We can also
control without acting, by the way; this is called "imagination" or
"thinking". We are not really controlling. But we creating the (imaginary)
perceptions we want on demand. This is all in B:CP by the way).
PCT has no accounts of visual recognition (or aural recognition, or haptic
recognition, or olfactory recognition or taste recognition). That means in
some sense it is a blind theory.
I really think you should re-read B:CP, especially the chapters describing
the levels. Bill makes some pretty clear proposals regarding the nature of
the perceptual functions that "recognize" ("compute" is a better word
because "recognize" implies that there is something out there to be
"recognized") sensations and sequences. I got my PhD in perceptual
psychology; I think PCT provides a very satisfying conceptual model of the
perceptual "recognition" functions, one that is based on the best evidence we
have from neurophysiology, psychophysics and machine recognition systems.
you have no account of how the visual system knows that the situation has
I just can't understand where you get this impression. Have you really read
And if you are interpreting the motor circuits as servo-loops maybe you
could get somewhere by doing the same for the similar visual circuits?
Both motor (efferent) and visual (afferent) neuronal connections are needed
to make a servo circuit. I can't figure out what you are talking about. What
is a "motor circuit"?
[your statement that] "I want a model where the inputs and outputs are
sensory" [suggests] that your understanding of PCT is _way_ different than
And here I thought I was suggesting a new arena where you (or someone) can
apply PCT. It's one thing for you to object when I tell you something like
an existing PCT account doesn't float. I may think your objection is wrong,
but I understand it. I tend to be like that myself. Who? me wrong? You
gotta' be kidding. But to be antsy over the possibility of going boldly
into new territory, shesh!
I must not be understanding what you mean by "I want a model where the inputs
and outputs are sensory". This doesn't sound like new territory; it sounds
like nonsense. In PCT, "sensory" means "signals caused by events in the
outside world". Inputs are the cause of sensory signals; outputs (eg. muscle
tensions) are caused by error signals. You seem to be saying that outputs
should also be the cause of sensory signals. In PCT, they are -- indirectly
(muscle tensions cause effects that are sensed). But I don't see how an
output can be sensory in the PCT sense -- ie. carry signals caused by events
in the outside world. If outputs were sensory then they would be inputs.
I can do a little more to make the idea intelligible. But not right this
minute. Gotta go.
I'll be here;-)