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- Date: Sat, 12 Dec 1992 04:55:22 -0700
- Sender: "Control Systems Group Network (CSGnet)" <CSG-L@UIUCVMD.BITNET>
- From: "William T. Powers" <POWERS_W%FLC@VAXF.COLORADO.EDU>
- Subject: Many subjects
- Lines: 231
-
- [From Bill Powers (921212.0300)]
-
- Might as well get the mail and write about it. What else can you
- do when you're awakened at such an hour to be told you have a new
- grandson (my daughter Barbara's second)?
- ---------------------------------------------------------------
- Len Lansky (921211.1143) --
-
- You raise an excellent set of questions. At a more propitious
- time I will start putting together an outline for a one-quarter
- (13-week) course in PCT. Unless someone else beats me to it. I
- envision a group project here, in which people rewrite the
- outline and re-rewrite it until we have something that looks
- good.
- --------------------------------------------------------------
- Rick Marken(921211) and Ed Ford (921210) --
-
- RE: Science and religion
-
- It will not be possible for science and religion to get together
- until both realize that neither is Revealed Truth, and that both
- are human ideas. Of course that is precisely what both sides have
- been rejecting since the start of science. One side points the
- finger at Nature, the other at God. Neither side, apparently,
- notices whose finger is doing the pointing.
- ----------------------------------------------------------------
- Gary Cziko (921210.1622) --
-
- The Little Man starts out (in the mapped mode) with a "bilateral
- lesion" that makes it consistently point short of (and to one
- side of) distant targets. As it builds up the map it gets closer
- and closer until it points exactly to the target on the first
- try. I suppose you could put a "lesion" in the map that
- selectively eliminates the correction in any dimension --
- horizontal, vertical, or depth.
- ----------------------------------------------------------------
- Bruce Nevin (921210.1206) --
-
- Come to think of it, language IS like grooming. Sometimes you
- pick up something nice and salty, but sometimes it wiggles and
- quirms until you crunch down on it.
- ----------------------------------------------------------------
- Oded Maler (921212) --
- RE: why is a theory of behavior necessary?
-
- Why is it necessary to have a theory of gravitation, or
- electronics, or numbers, or anything else? I suppose "necessary"
- is the wrong word here -- after all, other species have got along
- fine without any such theories. One can certainly jump and fall
- down without a theory of gravity, and behave without a theory of
- behavior, or even with a wrong theory of behavior. But theories
- in general seem to make sense of things in a way we can't achieve
- by any other means.
-
- Or were you specifically asking why we need a theory of behavior,
- in addition to all the other
- theories?---------------------------------------------------------------
- Penni Sibun (921211) --
-
- RE: Not "believing in" purpose.
-
- I was about to respond in a way almost identical to Rick's, by
- saying that purpose is the essence of control. But you then went
- on:
-
- >i think this ``virtual synonymy'' is a rhetorical move of pct's
- >that irritates people w/ a scientific bent (like me).
-
- If you think that the PCT interpretation of the meaning of
- purpose, or intention, or desiring, or wishing is a "rhetorical
- move" then you simply haven't caught on to the basic architecture
- of control.
-
- >i find yr generalization to everything else, including the
- >kinds of things implied by ``purpose,'' completely unwarranted.
- >so i wish you'd stick to making claims you can justify....
-
- What kinds of things do you think are implied by "purpose?" The
- PCT claim is that purpose is a perfectly real phenomenon,
- explainable by a proper model of control behavior. Purposive
- behavior is behavior that results in bringing some aspect of the
- environment or oneself or the relationship between them (as
- perceived) to a predetermined state, and maintaining it there for
- some time despite disturbances that tend to change it. This is
- the phenomenon that science mistakenly rejected in the early
- decades of this century, claiming that it required the future to
- affect the present and a number of other foolish things. The
- problem really was that science, at that time, lacked any
- explanation for purposive behavior, and at the same time assumed
- that what science could not explain (in, for instance, 1920) was
- mysticism, superstition, or illusion. That opinion prevails
- today, especially among scientists who still don't understand how
- control theory explains purpose. There are always scientists who
- think that what they can't explain in terms of the science of
- their time (the part they know about) can't be explained at all.
-
- Since you're the main person around here with a scientific bent,
- how about giving us the really scientific explanation of how a
- person carries out a purpose?
- -------------------------------------------------------------
- Wayne Hershberger (921211) --
-
- >What is wrong is supposing that the conceptual EVs are not part
- >of the model of the perceptual process! The light-ray tracings
- >in Bill's little stick man simulation comprise an integral part
- >of what works!
-
- There are others who would argue on your side -- some
- cyberneticists, in fact, claim that not only are the light-ray
- tracings part of the model, but that the outputs that alter the
- light-ray tracings are part of it, too. Basically they argue
- that any separation of the organism from its environment is a
- conceptual mistake. It's all just one big system, so there's no
- point in trying to take it apart into components in order to
- understand it. You can only understand, like, the WHOLE THING.
-
- I for one have never found that contemplating the WHOLE THING
- leads to anything but bafflement. I think that many people
- confuse this sense of bafflement with a sense of knowing.
-
- The light-rays are not only part of the perceptual processes,
- they are part of the output processes. We could just as well say
- that the actions of the Little Man consist of altering retinal
- images, or to go further that they consist of alterations in
- neural signals in the brain. In other words, it's all output,
- not perception. When you trace out the signal paths, you find
- that what we mistakenly call perceptual signals are really just
- part of the whole process of output.
-
- When you go far enough with this, you must finally decide that
- the outputs really consist of outputs, because when you start
- with the motor output forces and keep adding all the things
- directly related to and dependent on them, you end up back with
- the output forces after one trip around the loop. Making all the
- substitutions to eliminate intermediate terms, you end up with
- output = f(output). Or perception = f(perception), or error =
- f(error). It all depends on where you start.
-
- In our modeling efforts, we have found it definitely useful to
- distinguish the organism from its environment. When we do so, we
- find that the organism can know only what its senses tell it. And
- we find that what its senses tell it about the environment
- depends critically on how the sensory processes are organized.
- Two organisms in the same environment experience two different
- environments. Yet the mere fact that we can say "the same
- environment" means that we suppose that something does exist
- there independently of the perceiver. We can't prove that, but we
- can build models on the assumption that it's true.
-
- >... perceptual EVs and the conceptual EVs are lawfully related
- >to each other (I gather we agree fully on this point).
-
- Yes, but I doubt that you will agree with my agreement. I
- consider conceptual EVs to be higher-level perceptions of lower-
- level perceptual EVs, and that the lower-level perceptual EV's
- are in turn functions of variables in the Boss Reality. The
- higher-level "conceptual" EVs consist of such things as
- relationships, categories, sequences, logical and syntactical
- propositions, principles, and system concepts. Each successive
- level consists of perceptions that are functions of perceptions
- of lower level. The "lawful relationship" of which you speak is
- simply the relationship in which higher-level perceptions depend
- on lower ones according to the form of the higher-level
- perceptual function. If you look at the content of any
- "conception," you will find elements that correspond to the
- levels I propose -- and, I claim, nothing else. If you do find
- something else there, please let me know.
- I disagree, therefore, with the distinction between perception
- and conception as being too crude. I use the term "perception" to
- mean any afferent process at any level -- that is, anything we
- can experience. In place of the simple dichotomy perception-
- conception I substitute specific levels of apprehension of the
- world, and make the claim that these levels are hierarchically
- dependent. The general achitecture of the brain, and the effect
- of lesions and ablations in various parts of the brain, supports
- the view that the "conceptual" levels have access to the world
- only through lower levels of input processing. The highest levels
- have no direct access to the world -- there is no uninterrupted
- input path from the sensory organs.
-
- >It is this lawful relationship that allows us to use our
- >perceptual EVs to test our conceptual EVs in scientific
- >experiments. Science does not address the question of whether
- >our conceptual EVs (making sense of the immanent order)
- >correspond to those of some divine conceiver (God or Boss).
-
- You are fighting a straw man here. To hypothesize that there is a
- Boss Reality is not the same as saying that there is a Divine
- Conceiver. I'm surprised that you keep bringing this up -- surely
- you don't think that this is my explanation of the Boss Reality!
- You seem to be ruling out the possibility that there could simply
- be a universe that is independent of our experiences but on which
- our experiences depend. Or you seem to be saying that the only
- way such a universe could exist would be in the mind of a
- supernatural being.
-
- This truly puzzles me. I don't see how you arrive at just those
- possibilities. The only possible clue I can get is in this:
-
- >That relationship [between concept and percept] is the basis of
- >empiricism.
-
- and this:
-
- >Not only does the immanent order have many more degrees of
- >freedom than we can perceive, it may have more degrees of
- >freedom than we can conceive.
-
- It seems clear to me that what you are calling the "immanent
- order" is what I call the "Boss Reality." Models are a way of
- conjecturing about what might exist in the immanent order that we
- have not yet perceived. We imagine, in other words. We provide
- for ourselves lower-level perceptions synthesized from memory,
- and view them from higher levels as if they exist in real time.
- We categorize and characterize them, we reason about them, we
- form principles on their basis, we fit them into a systematic
- concept of the world. And we test them: we create outputs
- calculated to produce certain perceptions after passage through
- that external world as we model it, and check to see if the
- result is what we expected.
- Of course we must always cast these conjectures in the form of
- human perceptions. We have no other way of experiencing the boss
- reality.
-
- Perhaps all of this comes down to the same concept that you call
- "empiricism." But I think you may have more faith in empiricism
- than I do, as a source of true knowledge.
- ----------------------------------------------------------------
- Best to all,
-
- Bill P.
-