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- From: POWERS_W%FLC@VAXF.COLORADO.EDU (William T. Powers)
- Newsgroups: bit.listserv.csg-l
- Subject: MESSAGE FROM MARY
- Message-ID: <01GR0ZXDRDO200005H@VAXF.COLORADO.EDU>
- Date: 11 Nov 92 20:44:13 GMT
- Sender: "Control Systems Group Network (CSGnet)" <CSG-L@UIUCVMD.BITNET>
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-
- [from Mary Powers 921111]
-
- Jixuan Hu:
-
- You can tell that Bill Powers is pretty disenchanted with the
- ASC. Actually, the Control Systems Group was, in 1983 and 1984, a
- group within the ASC, but after two meetings in which we found we
- were only talking to each other, we began to meet independently.
- Some of us attended further ASC meetings, and you might want to
- look up The Conference Workbook for "Texts in Cybernetics" for
- the ASC meeting in Felton, California if you want to compare
- Glassersfeld, Maturana, and Powers. The Powers text from that
- book is also reprinted in Living Control Systems I. But you
- should read his Behavior: the control of perception.
-
- The ASC deals in abstract generalizations, and PCT is concerned
- with modelling organization. They both are founded on Wiener's
- book, which by the way is about control and communication, not
- communication and control. But cybernetics has always downplayed
- control, while PCT considers it fundamental.
-
- Everybody:
-
- I am getting requests for information about CSG from netters and
- by snail mail. The following is what I am sending out (the
- bibliography is shamelessly cribbed and edited from Dag's). I
- would appreciate suggestions and revisions (keeping in mund that
- the PCT section is at max length since I have postage
- considerations and can fit everything now on two double-sided
- pages)
-
-
- Perceptual Control Theory
-
- While the existence of control mechanisms and processes (such as
- feedback) in living systems is generally recognized, the
- implications of control organization go far beyond what is generally
- accepted. We believe that a fundamental characteristic of organisms
- is their ability to control; that they are, in fact, living control
- systems. To distinguish this approach from others using some
- version of control theory but forcing it to fit conventional
- approaches, we call ours Perceptual Control Theory, or PCT.
-
- PCT requires a major shift in thinking from the traditional
- approach: that what is controlled is not behavior, but
- perception. Modelling behavior as a dependent variable, as a
- response to stimuli, provides no explanation for the phenomenon
- of achieving consistent ends through varying means, and requires
- an extensive use of statistics to achieve modest (to the point of
- meaningless) correlations. Attempts to model behavior as planned
- and computed output can be demonstrated to require levels of
- precise calculation that are unobtainable in a physical system,
- and impossible in a real environment that is changing from one
- moment to the next. The PCT model views behavior as the means by
- which a perceived state of affairs is brought to and maintained
- at a reference state. This approach provides a physically
- plausible explanation for the consistency of outcomes and the
- variability of means.
-
- The PCT model has been used to simulate phenomena as diverse as
- bacterial chemotaxis, tracking a target, and behavior in crowds.
- In its elaborated form, a hierarchy of perceptual control systems
- (HPCT), it has lent itself to a computer simulation of tracking,
- including learning to track, and to new approaches to education,
- management, and psychotherapy.
-
- Control systems are not new in the life sciences. However,
- numerous misapprehensions exist, passed down from what was
- learned about control theory by non-engineers 40 or 50 years ago
- without further reference to newer developments or correction of
- initial misunderstandings. References in the literature to the
- desirability of positive feedback and the assertion that systems
- with feedback are slower than S-R systems are simply false, and
- concerns about stability are unfounded.
-
- The primary barrier to the adoption of PCT concepts is the belief
- - or hope - that control theory can simply be absorbed into the
- mainstream life sciences without disturbing the status quo. It is
- very hard to believe that one's training and life work, and that
- of one's mentors, and their mentors, must be fundamentally
- revised. Therefore, PCT appeals to those who feel some
- dissatisfaction with the status quo, or who are attracted to the
- idea of a generative model with broad application throughout the
- life sciences (plus AI and robotics). There are very few people
- working in PCT research. Much of its promise is still simply
- promise, and it meets resistance from all sides. It is
- frustrating but also tremendously exciting to be a part of the
- group who believe that they are participating in the birth of a
- true science of life.
-
- ________________________________________________________________
-
- BIBLIOGRAPHY
-
- Powers, William T., Behavior: The Control of Perception.
- Hawthorne, NY: Aldine DeGruyter, 1973.
- The basic text.
-
- *Robertson, Richard J. and Powers, William T., editors.
- Introduction to Modern Psychology: the Control Theory View. CSG
- Books, 1990. ($25 postpaid)
- College-level text.
-
- *Powers, William T., Living Control Systems I : selected papers.
- CSG Books, 1989. ($16.50 postpaid)
- Previously published papers, 1960-1988.
-
- *Powers, William T., Living Control Systems II : selected papers.
- CSG Books, 1992. ($22 postpaid)
- Previously unpublished papers, 1959-1990.
-
- *Marken, Richard S, Mind Readings : experimental studies of
- purpose. CSG Books, 1992. ($18 postpaid)
- Research papers exploring control.
-
- Marken, Richard S., editor. Purposeful Behavior : the control
- theory approach. Thousand Oaks, CA: Sage Publications: American
- Behavioral Scientist, special issue. Vol. 34, Number 1.
- September/October 1990.
- 11 articles on control theory.
-
- Runkel, Philip J., Casting Nets and Testing Specimens. New York:
- Praeger, 1990., 186 pages.
- When statistics are appropriate; when models are required.
-
- Hershberger, Wayne, editor, Volitional Action : conation and
- control. Advances in Psychology 62. NY: North-Holland, 1989.
- 25 articles (not all PCT)
-
- Ford, Edward E., Freedom From Stress. Scottsdale AZ: Brandt
- Publishing, 1989.
- A self-help book. PCT in a counseling framework.
-
- Gibbons, Hugh, The death of Jeffrey Stapleton : exploring the way
- lawyers think. Concord, NH: Franklin Pierce Law Center, 1990.
- A text for law students using control theory.
-
- McClelland, Kent, Perceptual Control and Sociological Theory.
- 1992.
- Not yet published. Available from the author, Grinnell
- University, Grinnell, Iowa.
-
- McPhail, Clark, The Myth of the Madding Crowd. Hawthorne, NY:
- Aldine de Gruyter, 1990.
- Introduces control theory as a way to explain group
- behavior.
-
- McPhail, Clark, Powers, William T., and Tucker, Charles W.,
- Simulating Individual and Collective Action In Temporary
- Gatherings. Social Science Computer Review, 10:1, Spring 1992.
- Durham, NC, Duke University, 1992.
- Computer simulation of control systems in groups.
-
- Petrie, Hugh G., Dilemma of Inquiry and Learning. Univ. of
- Chicago press, 1981.
- Introduces PCT to educational theory.
-
- Richardson, George P., Feedback Thought in Social Science and
- Systems Theory. Univ. of Pennsylvania Press, 1991.
- A review of systems thinking, icluding PCT.
-
- *These items are available from CSG Books, 460 Black Lick Road,
- Gravel Switch, KY, 40328.
-
- ______________________________________________________________
-
- The Control Systems Group
-
- The CSG is an organization of people in the behavioral, social,
- and life sciences who see the potential in PCT for increased
- understanding in their own fields and for the unification of
- diverse and fragmented specialties. We maintain a computer
- network, and also have a publication, Closed Loop: threads from
- CSGnet. Net subscribers find it useful to have thematic
- collections of some of the network discussions, and it enables
- non-net members to keep up with them.
-
- Closed Loop is published quarterly. It is sent only to members,
- who pay $45 a year. This sum supports student subscriptions,
- which are $5. Any surplus after production and mailing, plus a
- few organizational expenses, is used to help defray costs for
- students wishing to attend the annual meeting.
-
- The annual meeting is held in Durango, Colorado, on the campus of
- Fort Lewis College. In 1993 it will begin in the evening of
- Wednesday, July 28, and end Sunday morning, Aug, 1. There will be
- 7 plenary meetings (mornings and evenings), with afternoons,
- mealtimes, and late night free for further discussion or
- recreation. Full details will be available on the net or by mail
- after April 1, 1993.
-
- To subscribe to the net, this is the address:
-
- LISTSERV@VMD.CSO.UIUC.EDU
-
- send this message:
-
- SUBSCRIBE CSG-L Lastname Firstname Location/Affiliation
-
- To join CSG, receive conference information, etc., write to
-
- The Control Sustems Group
- Mary A. Powers
- 73 Ridge Place
- Durango CO 81301-8136
-
- A complimentary copy of Closed Loop will be sent upon request.
- Back issues are available: Volume 1 (4 issues) is $12. Single
- issues of Volume 2, beginning with Jan. 1992, are $6 each.
-
- -----------------------------------------------------------------
- penni:
-
- I appreciate your gripe about the cost of CSG membership and
- hereby offer you a limited-income membership for $20. (Anyone who
- objects is welcome to impeach me. Chuck? Wayne?)
-
- Rick:
-
- >You can't tell what people are doing by watching what they are
- >doing.
-
- No indeedy. You apply the Test for the Controlled Quantity. I ran
- across a nice quote about the Test. Almost 3 centuries old.
-
- Search then the ruling passion; there alone
- The wild are constant, and the cunning known;
- The fool consistent, and the false sincere;
- Priests, princes, women, no dissemblers here.
- This clue once found unravels all the rest.
-
- Alexander Pope, 1688-1744
-
- Happy unravelling!
-
- Mary P.
-
-