[From Dag Forssell (950213 1600)]
I have offered a "PCT Introduction and Resource Guide" in printed
form since last spring. With the advent of World Wide Web, I have
taken the time to convert it to an ASCII file. This is three times
longer (75 KB) than INTROCSG.NET (28 KB). Gary Cziko will place it
on his WWW server.
Best, Dag
···
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PCT Introduction and Resource Guide Page one
PCT INTRODUCTION AND RESOURCE GUIDE
Perceptual Control Theory (PCT) offers a clear explanation for the
pervasive phenomenon of simple control. Hierarchical PCT outlines
a hierarchical arrangement as the likely organization of multiple
control systems in humans. It explains how thoughts become
actions, results and feelings. This sheds new light on important
issues of leadership, education, economics and personal
relationships in business, society and families. This introducion
and resource guide is intended to allow you to determine your own
level of interest and search out information you want.
LOOK UNDER THE HOOD OR TAKE A TEST RIDE?
If this is your first encounter with PCT, you might think of
yourself and others as experienced with horses when the newfangled
PCT automobile drives into town, introducing a new science and new
possibilities. Some people will stick with the familiar horse,
some will want to kick the tires and learn all about how the engine
works to evaluate the auto, and some will want a test ride.
If you would rather take a test ride first, to get a feel for the
PCT approach to travel, I suggest you go to Freedom From Stress by
Edward E. Ford (page 14 and 16). You tour the landscape and watch
Ed drive while he gives you a summary explanation of how a car
works and why he teaches driving the way he does, in an easy-to-
read counseling story that deals with relationships at work, in
marriage, and with children.
To become an expert driver yourself, able to think and deal with
conflict like Ed does in real time, you may want more in-depth
understanding. Proceed to other books and programs in this guide
for a more complete education. You might be inspired to become a
PCT engineer yourself, join the Control Systems Group to do
research and find better ways to drive on the many roads of human
experience.
WHAT PCT IS (PCT in a nutshell, pg 8, The nature of HPCT, pg 12).
Let me explain my view of what PCT (here including the extension
"Hierarchical PCT (HPCT)) is by relating it to "reverse-
engineering." Suppose you manufacture microelectronic products and
your competitor has just introduced a new and better one. It is
difficult to figure out how the new device was designed, because it
is made up of millions of simple components with intricate
connections.
In order to be able to make a fully equivalent device, you decide
to "reverse-engineer" it. This means that you 1) observe what the
device does (how it behaves), and 2) come up with an explanation
for the behavior which leads to a workable design for a circuit (or
more generally, a physical mechanism), which will perform just like
your competitor's device does--in fact, be the same device.
As a science explaining or "reverse-engineering" human beings,
contemporary psy-chology has spent most of its time on step 1) and
has tried but failed with step 2). PCT proposes an organization
or model of the nervous system. We can test the PCT model by
letting it behave by itself, and compare the result with the
behavior of the real thing--people. Tests suggest further
refinement. Since it is ourselves we reverse-engineer, we
naturally require that the explanation and model we come up with
feels right; that it intuitively makes sense to us when we are told
how we work. Multiple tests and personal experience indicate that
PCT is a valid model. PCT appears to be the first approach to step
2) that holds up to critical scientific scrutiny and is worth
refining.
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PCT Introduction and Resource Guide Page two
APPLYING PCT
To drive a car, it is important to know how the controls work, but
it is not necessary to understand how the engine works--you can
leave that to the engineers. To apply PCT in daily life, it is
important to understand the basic concept, but it is not necessary
to understand all the technical details--you can leave that to the
PCT engineers.
You drive a horse without understanding how the mind of the horse
works. You learn from experience how the horse responds to your
commands, but sometimes it does not respond the way you expect, and
that can be frustrating. The PCT auto is really the same horse
(any living organism or a human being--yourself), but with a
different understanding. When you understand the basic concept of
PCT, you will observe yourself and others and at the same time
visualize the internal mechanism in action. Your understanding of
the internal mechanism gives you greater ability to have an
enjoyable ride through life and to show others how to enjoy theirs,
too.
WHERE PCT COMES FROM
PCT is the creation of one mans background, curiosity and determi-
nation. William T. (Bill) Powers learned about control systems
and analog computers--key for the development of PCT. He studied
physics and other applied physical sciences necessary to reverse--
engineer the human nervous system. Bill's seminal book Behavior:
The Control of Perception, published in 1973, is still in print and
is must reading for the serious PCT student. When you order it,
you will no longer get a jacket, so I have reproduced the original
book jacket on page 3-4. Note comments by Russell L. Ackoff, Carl
R. Rogers, and Thomas S. Kuhn among others. A prolific, lucid
writer, Bill has also collaborated in the creation of a college
text. Living Control Systems I & II are collections of his
papers. Page 15.
Seeing how control works is better than reading about it. For
demonstration programs simulating an analog control system on a
digital PC, tutorials, simulations, explanations and discussions,
see PCT demos, page 14.
In this guide, I have included two short essays: An essay on the
obvious, p. 9-10 and Things I'd like to say if they didn't think
I'm a nut, p. 11. Bill writes about what is required for
psychology to progress as an applied physical science.
RESEARCH AND DEVELOPMENT
An introduction to the Control Systems Group (CSG) and E-mail
network (CSG-L, address on page 20) is included in the book
Management and Leadership: Insight for effective practice. and
computer diskette PCT demos, page 14.
APPLICATIONS AND LITERATURE
The information on books, articles, seminars, video tapes and
computer disk available should be self-explanatory. Welcome to
PCT!
Dag C. Forssell December 12, 1994
Valencia, California Rev. Feb. 10, 1995
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PCT Introduction and Resource Guide Page three
BEHAVIOR: THE CONTROL OF PERCEPTION by William T. Powers
A reproduction of the original book jacket:
"Powers' Behavior: The Control of Perception gives social
scientists--finally--an alternative to both behaviorism and
psychoanalysis. It provides a way, both elegant and sophisticated,
to include the basic contributions of both without being partisan
or converted. It allows us to bring the soma, culture, society,
behavior, and experience into a single framework. We now know much
more than we did before this book was published.
--Paul J. Bohannan, Stanley G. Harris Professor of Social
Science, Northwestern University; author of _Divorce and After,
Social Anthropology_, and other books.
The highly original thesis of this remarkable book is deceptively
simple: that our perceptions are the only reality we can know, and
that the purpose of all our actions is to control the state of this
perceived world. This simple thesis represents a sharp break with
most traditional interpretations of human behavior. The theory set
forth and developed in detail in this book proposes a testable
model of behavior based on feedback relationships between organism
and environment, which can reconcile the conflict between behavior-
ists and humanists and for the first time put us on the road to an
understanding of ourselves that is at once scientific and humane.
The model advanced here explains a range of phenomena from the
simplest response of a sensory nerve cell to the construction of a
code of ethics, using cybernetic concepts to provide a physical
explanation not only for physical acts but also for the existence
of goals and purposes. A hierarchical structure of neurological
control systems is proposed that is at least potentially
identifiable and testable, in which each control system specifies
the behavior of lower level systems and thus controls its own
perceptions.
The model incorporates the "programming" of behavior in the course
of human evolutionary history, the nature and significance of
memory, and the reorganizations of behavior brought about by
education and experience.
Written with verve and wit, with many illuminating examples and
interesting thought questions, _Behavior: The Control of
Perception_ may well prove to be one of the truly seminal works of
our time; at least, this is suggested by the distinguished scholars
who read the manuscript in advance of publication (see back cover).
The book suggests many new interpretations of neurological,
behavioral, and social data, an immense range of new experiments
that will modify the model advanced here, and much new insight into
such crucial psychological and social processes as education, the
resolution of conflict, and the problems of mental illness.
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ABOUT THE AUTHOR
William T. Powers received his B.S. in physics and did his graduate
work in psychology at Northwestern University. He has consulted
for The Center for the Teaching Profession, and was formerly Chief
Systems Engineer of the Department of Astronomy at Northwestern.
He has published articles in psychology, astronomy and electronics,
and has invented and designed a number of electronic instruments.
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For ordering information, see page 18.
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PCT Introduction and Resource Guide Page four
The original book jacket, continued:
Russell L. Ackoff, Silberberg Professor of Systems Sciences,
University of Pennsylvania; Past President of the Operations
Research Society of America; author of _The Design of Social
Research_, co-author of _On Purposeful Systems, fundamentals of
Operation Research_, and other books.
"Publication of William Powers' book, _Behavior: The Control of
Perception_, is, in my opinion, a major event in the development
of the psychology of perception. The completely new approach he
has developed using cybernetic concepts cannot help but be
seminal, instigating a new and important line of investigation
of a wide range of psychological phenomena in addition to
perception. His new way of looking at and conceptualizing old
things will help to open the way for a series of important
discoveries, and these--because of the rigorous framework he
provides--are likely to be sounder scientifically than most of
the earlier work that they will displace."
Donald T. Campbell, Professor of Psychology, Northwestern Universi-
ty; Past President Of the Division of Personality and Social
Psychology of the American Psychological Association, co-author of
_Unobtrusive Measures_ and other books and articles.
"Powers' book is, I am convinced, the very best job to date in
the application of feed-back theory (servo-system theory,
cybernetics) to psychology. Unlike all of its many
predecessors, Powers' book comes up with elegant, relevant, and
novel detail. It is the first to really capture the promise of
cybernetics. It achieves this by bringing to psychology the
concept of the 'reference signal' from servo-system theory, and
by an explicit hierarchy of 'orders' of control systems."
Thomas S. Kuhn, Professor of the History of Science, Princeton
University; author of The Structure of Scientific Revolutions.
"Powers' manuscript, _Behavior: The Control of Perception_, is
among the most exciting I have read in some time. The problems
are of vast importance, and not only to psychologists; the
achieved synthesis is thoroughly original; and the presentation
is often convincing and almost invariably suggestive. I shall
be watching with interest what happens to research in the
directions to which Powers points."
John R. Platt, Research Biophysicist and Associate Director of the
Mental Health Research Institute, University of Michigan; author of
_Perception and Change: Projections for Survival and Step to Man_.
"Powers has made an important new synthesis in applying the
concept of hierarchical levels of feedback-control systems to
brain organization and behavior. His ideas throw new light on
neural and brain structure, the role of reafferent stimulation
in perception and behavior, hierarchical control mechanisms,
goal-seeking and feedback at different levels of organization,
and epistemology. The book is written in an easy and personal
tone with numerous illuminating examples to illustrate the main
new points, and with interesting thought-questions at the end of
each chapter."
Carl R. Rogers, Resident Fellow of the Center for Studies of the
Person, La Jolla, California; Past President of the American
Psychological Association and recipient of its Distinguished
Scientific Contribution Award in 1956; author of _Freedom to
Learn_, _On Becoming A Person_, and other books.
"Here is a profound and original book with which every psycholo-
gist--indeed every behavioral scientist--should be acquainted.
It is delightful to have a person of such varied and unorthodox
background come forth with a unique theory of the way in which
behavior is controlled in and by the individual, a theory which
should spark a great deal of significant research."
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PCT Introduction and Resource Guide Page five
FOREWORD TO LIVING CONTROL SYSTEMS II (see page 15).
In 1979, Bill Powers wrote a prophecy: "A scientific revolution is
just around the corner, and anyone with a personal computer can
participate in it.... [T]he particular subject matter is human
nature and in a broader scope, the nature of all living systems.
Some ancient and thoroughly accepted principles are going to be
overturned, and the whole direction of scientific investigation of
life processes will change." (William T. Powers, "The Nature of
Robots: Part 1: Defining Behavior," BYTE 4(6), June, p. 132)
Powers foresaw the overthrow of the idea that either stimuli from
the environment, or commands from the mind or brain, are sole
causes of behavior. In its place, he offered the concept that
people (and in their own ways all other organisms) intend that they
will experience certain perceptions and behave to cause the
perceptions they intend. The social, behavioral, and life sciences
had simply missed the fact that living things control many features
of their environments. Powers acknowledged that fact, and he
realized that to an organism the environment exists only as
perceptions, hence his insight that organisms act to control their
own perceptions. His formal statement of the new concept was
control theory, and he said amateurs, working with personal
computers on their tables at home, would be major players in the
revolution. Thirteen years later, the revolution is not accom-
plished, but it is underway.
Powers' perceptual control theory is new, but he is not the first
to describe many of the key ideas in the theory. Over 2200 years
ago, Aristotle wrote about intention--"that for the sake of which,"
the desire or wish that causes actions that result in a particular
end. Aristotle used many examples in which a person acts to produce
an intended object, such as a bed, statue, tray, or house. The
person's intention to create the object is the "final cause" of the
actions that produce the object. Aristotle wrote that, depending on
the condition of the world and the intention of the person, the
same actions sometimes produce different ends, and different
actions sometimes produce the same end. All of that sounds like
good control theory, so why are those ideas considered revolution-
ary today?
For many centuries, Aristotle's ideas disappeared from Europe and
were preserved by scholars in the Arab world. They returned, in
altered form, to a Europe dominated by Christian theology.
Theologians changed "final cause," which to Aristotle often meant
only a person's intention to manufacture a bed out of wood, into
God's original plan for the linear unfolding of history, from
creation, to Calvary, to Apocalypse, to the end of time.
Aristotle's original idea was unrecognizable.
Most early European scientists worked within Christian theology,
embracing its notion of linear time and its implication of linear
cause and effect. Many of these scientists mistakenly assumed that
the original concept, that a final cause is a goal, implied that
the future influences the present--a clear violation of the assumed
linear flow of cause and effect. Eventually, potentates of The
Church and potentates of Science came to a falling out over dogma.
Those who established the canon for Science had yet another
mistaken reason to reject final cause: they said it represented an
appeal to the supernatural, in the form of God as agent. The idea
that there is purpose or intention in the behavior of any living
thing was pronounced "unscientific." Most aspiring behavioral and
biological scientists still affirm that credo.
When William James wrote one hundred years ago, the ideas of
purpose and intention were popular again. James said purposive
behavior is the distinguishing feature of intelligence--of life. He
said that in a variable world an organism's behavior necessarily
varies to produce unvarying intended results. James wrote that
people do not intend their specific actions; they intend to
experience perceived consequences of their actions, then they vary
their actions any way necessary to produce those perceptions. For
a while, it looked as though the idea of intention might take hold,
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PCT Introduction and Resource Guide Page six
but once more the idea was purged from the sciences of behavior and
life. Orthodox scientists asserted that intention implies final
cause, which necessarily implies an appeal to supernatural forces
and to a temporal reversal of causality. Purposive behavior was
banished, on the one hand by behaviorists, environmentalists, and
reflexologists who claimed that events in the environment determine
behavior, and on the other by those who claimed that instincts
acting as internal stimuli cause behavior. People on either extreme
believed their positions were dramatically different, but they all
portrayed behavior as the end result of a linear chain of cause and
effect.
Powers writes at a time when purpose and intention remain unaccept-
able to most scientists. Behaviorists still believe environmental
"stimuli" have the "power" to control behavior; and most cognitive
scientists and neuroscientists say the mind-brain issues "commands"
that cause muscles to produce appropriate behavior.
Cognitive-neuroscientists frequently claim behaviorism is dead and
a cognitive revolution has swept the behavioral and life sciences;
in return, behaviorists pronounce themselves very much alive, and
some portray cognitive theorists as "creation scientists," bent on
keeping alive the concept of soul-as-mind. Once again, each camp
believes its views differ markedly from those of the other, but
both embrace the wearisome model of linear cause and effect--a
model that was necessary a few hundred years ago to establish the
physical sciences, but a model that mistakenly rejects what Powers
recognizes as the defining properties of life. Neither wing of the
cause-effect orthodoxy recognizes the abundant evidence that
organisms control many parts of their world. But revolutions have
a way of changing the minds of the orthodox.
Powers turned the millennia-old idea that living systems act to
produce intended perceptions into a formal theory of behavior:
perceptual control theory. Perceptual control theory identifies
behavior as the necessarily variable means by which organisms
control their perceptions of the world. Working first on a
build-it-yourself computer (the one he used when he wrote his
prophecy), then on a first-generation IBM personal computer, Powers
created elegant demonstrations in which the
simple-idea-turned-formal-model generates remarkably accurate
quantitative simulations and predictions of behavior and its
consequences. He identified a first principle for behavioral,
social, and life sciences and showed the way to a new foundation of
theory and method.
For several years, only a few people followed Powers' lead, and
even fewer gathered the data and performed the modeling that could
establish control theory as an alternative to traditional science.
But interest in the theory grew--a tribute to the dogged efforts of
William and Mary Powers, over three decades, to maintain the
visibility of the theory. During most of that time, Powers
published only one book and a few papers. More recently, informa-
tion about control theory burst into wider circulation through two
functions of personal computers that no one predicted in 1979:
desktop publishing and electronic-mail networks. Those applications
freed perceptual control theory from the heavy hands of editors and
reviewers who routinely rejected manuscripts on the theory. They
were true defenders of cause-effect orthodoxy, rejecting control
theory as uninteresting and unnecessary, or as merely another way
to describe things that were already understood. The new media let
many people see control theory, then judge it on its own merits.
The once-small circle of people aware of the theory grew into a
network spanning the world, including people from many disciplines,
specialties, and professions. And the demand for Powers' writings
grows.
In the Foreword to the first volume of Living Control Systems,
Richard Marken wrote about the difficulty he experienced several
years ago when he tried to locate published material by Powers.
Volume I was a collection of Powers' published work But Powers has
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PCT Introduction and Resource Guide Page seven
written far more than he has published. When he writes, Bill does
not revise his drafts. If he encounters a block or is dissatisfied,
he starts over. He has cast aside several beginnings of books and
many drafts of chapters and papers that he never submitted, or that
were rejected by editors and reviewers. Most of us would be happy
if any of our publications equalled the quality of the work Bill
put away in drawers and boxes and, more recently, on disks.
Over the years, only a few people have had a chance to read parts
of Bill Powers' unpublished work. The opportunity to rummage about,
looking for those gems, was at least part of "that for the sake of
which" some of us travelled to his 'laboratory" in the back room of
his home in Northbrook, Illinois. When Mary and Bill decided to
move to Colorado, Edward Ford, a counselor in Arizona, suggested
that the mandatory gathering of possessions into boxes provided an
excellent chance to select part of Bill's unpublished work for an
edited volume. Greg Williams, a frequent visitor to Northbrook,
journeyed there from Kentucky for the last time to gather the pages
and disks and take them away so he could select the pieces in this
volume.
This volume contains a small sample of the previously unpublished
material from the years when Bill and Mary Powers were in
Northbrook. If you want to rummage through the next accumulation,
you must travel to the new site of The Laboratory of William T.
Powers. That is the locus of many of today's clearest insights into
purposive behavior. Over the millennia, that locus has moved from
Aristotle's Lyceum, to James' Harvard, to Northbrook, and now to a
house atop a ridge near Durango, with a view of the San Juan
Mountains, located only a few miles away, across a broad valley--a
view that, years ago in Illinois, Mary and Bill Powers said they
intended to see out their back door. Stated intention, actions, and
perceived consequences that match the intention. It looks like
control to me!
February 1992
On the Phenomenon of Control. In the foreword above, I sketched a
history of the often-rejected idea that living things act to
control their own experiences. There is also a long history of
devices that mimic control by a person. In classical times,
observers of manufactured control devices often identified them as
"mysterious" or "miraculous." There were lighted lamps in which the
wicks and oil were never consumed, and vessels in which, no matter
how much was consumed, the levels and flows of water or wine never
changed, and statues that seemed to move of their own accord. The
"miraculous" phenomenon of control was there for all to see, but
the ingenious devices that actually controlled were hidden from
view and the principles of control went unrecognized.
Centuries later, the metaphor of the machine was dominant in
European thought. People were compared to lineal machines,
embodying discrete, sequential cause and effect. The idea that
people resemble machines soon gave way to the still-popular
assertion that people are lineal cause-effect machines. Overextend-
ed metaphors aside, the design, and eventually the theory, of
control devices moved on, from a variety of hydraulic and mechani-
cal governors and regulators in the 1600s and 1700s, to electronic
controllers in the 1920s and 1930s. Today, control devices are
ubiquitous, yet most people who say a person is a machine (probably
a computing machine), mean people are lineal cause-effect machines,
not controllers or regulators.
To most people, the phenomenon of control typically goes unnoticed
or unacknowledged, whether the controller is a living system, or an
ingenious device. Control: it is everywhere, and everywhere it is
denied.
December, 1994. W. Thomas Bourbon
University of Texas Medical School-Houston
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