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Perceptual Control Theory (PCT)
And the On-Going Evolution of Culture
Version 1.01 Beta
©April 2008
F. T. Cloak, Jr.
#SLIDE 1#.
Culture"
"Perceptual Control Theory(PCT) and the Evolution of
#SLIDE 2#. Darwin showed that living things evolve by the natural
selection of biological features; i.e., he showed how evolution works.
But he could not show how natural selection works, because he didn't
know about genetics. Later on, we learned how natural selection works
through the rediscovery of Mendel and the resulting New Synthesis.
#CLICK01#
Richard Dawkins and I, building on the work of George Williams and
others, and after demonstrating the primacy of genes as units of natural
selection, argued that culture evolves through the natural selection of
cultural features. #CLICK02# But we could not show how that works,
because we lacked a comparable theory of cultural transmission.
#CLICK03#
As I've said previously, I think William T. Powers's Perceptual Control
Theory, or PCT, may help us to address that lack. #CLICK04# Indeed, as
I intend to show here, by providing a robust hypothesis about culture
acquisition, PCT may actually reveal the elemental units of culture and
cultural evolution.
#SLIDE 3#. PART ONE. PERCEPTUAL CONTROL THEORY (PCT)
Perceptual Control Theory -- PCT -- challenges conventional assumptions
about behavior, by asserting that when an organism acts it is invariably
comparing its perceptions to perceptual reference standards stored in its
nervous system, and that it will continue to act until its perceptions
approximate those standards. #CLICK#
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The neuroanatomy and physiology of perceptual control is a product of
hundreds of millions of years of evolution. The reference standards, too,
are products of blind variation and selective retention -- genetic evolution,
learning by individual carriers, and, in some species, cultural evolution.
Thus the perceptual control apparatus is adapted to early and recent past
environmental conditions -- both within and outside of the carrying
organism. #CLICK#
The perceptions which the apparatus controls are, however, perceptions
of the organism's current environmental conditions, as detected by its
sensory cells, inferred by its neural input machinery, and stored in its
memory.
PCT thus understands behavior not as simple responses to immediate
stimuli, but as the maintenance of historically established states of the
nervous system in the face of variations in its immediate surroundings.
#SLIDE 4#. The elemental neural mechanisms by which normal
perceptual control occurs, the units of behavioral organization, are
perceptual control systems, or CSes. As we shall see, CSes operate in
functional hierarchies in the organism's central nervous system, each
CS-in-a-hierarchy evoking reference standards in CSes below it.
Each individual CS consists of #CLICK01# an input function, #CLICK02# a
comparator function, #CLICK03# an output function, #CLICK04# and
memory in which its reference standards are stored.
The Input Function #CLICK05# receives perceptual signals from one or
more CSes lower in the hierarchy or from sensory cells, and consolidates
those signals, #CLICK06# producing its own perceptual signal,
#CLICK07# which it sends to the Comparator #CLICK08# and passes on
to a higher-level CS, #CLICK09# while storing some of it in memory.
From time to time, #CLICK10# Memory receives an address signal from a
higher-level CS’s Output Function, #CLICK11# determines the bestmatching reference standard, #CLICK12# and sends that to the
Comparator. Unless the input signal and the reference signal agree,
#CLICK13# the Comparator sends an error signal to the Output Function,
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#CLICK14# which in turn sends signals addressing one or more lowerlevel CSes or reaching outside the CS realm to stimulate one or more
muscles.
Signals are not generally simple. #CLICK15# Indeed, they may vary
enormously in the amount of information they carry. The signals of a
mid-level CS might be comparable in bandwidth to signals of highdefinition television, complete with sound.
#SLIDE 5#. So here’s a typical CS in its resting state. Perceptual signals
come in constantly, and are processed and passed on. But when a
higher-level CS addresses #CLICK01# -- in other words, Googles -- a
CS's memory, it springs into action. Selecting from stored perceptions
which match the address signal, #CLICK02# memory sends a
reference signal to the comparator. If the comparator determines
#CLICK03# that the perceptual signal from the Input Function
sufficiently approximates the reference signal, it does nothing. In other
words, its surroundings appear, to this particular CS, to be O.K., so no
action is necessary on its part.
But if the perceptual signal does not sufficiently approximate the
reference signal, #CLICK04# the comparator sends an error signal to the
output function, #CLICK05# which in turn generates address signals to
lower-level CSes or directly to muscles.
#SLIDE 6#. The organism acts, and thus perhaps changes how their
surroundings appear to its CSes, in particular to the CS we are talking
about. This negative feedback process is repeated -- at several times
per second -- until the comparator is satisfied that the signal from the
Input Function #CLICK01# adequately approximates the reference
signal. /comparator animation stops/comparator output stops/output
animation stops/output output stops/#CLICK02# surroundings
animation stops
Note that even though the comparator of this CS is satisfied, the
comparator of a higher-level CS may not be satisfied with its perceptions,
#SLIDE 7#. so it may send down a different address signal, #CLICK#
altering or restarting the process here at this level.
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So from this we see that each CS uses CSes below it to control its
perceptions and, in turn, is similarly used by the CSes above it.
#SLIDE 8#. Now let's take a look at the way CSes are linked together
to interact in an animal's nervous system.
#CLICK01# A three-dimensional schematic diagram of CS interaction
would show the CSes arranged in a number of concentric spheres, rather
like an onion. #CLICK02# …
#SLIDE 9#. The CSes in the outermost sphere or layer are connected
to sensory cells and muscles.
#CLICK# CSes in each layer are connected to CSes in layers closer to the
center, passing perceptual signals to them, and, as needed, receiving
address signals from them.
#SLIDE 10#. An organism of any complexity thus has thousands of CSes
acting at the same time, each CS a module in at least one interactive
hierarchy.
#CLICK01# Through evolution, learning, and culture this cacophony of
nervous activity has become a fairly well integrated parliament of CS
modules. The underlying neural machinery can have been devised only
by natural selection, operating on the animal nervous system over
hundreds of millions of years.
#SLIDE 11#. The hierarchy of CS modular levels is not hard and fast,
and is still being researched, but the general principle surely holds.
Powers's most recent listing of CS levels, starting with the outermost, or
bottom level, includes
a. #1# CS modules controlling perceptions of Intensities of
stimulation - of sensory nerve-endings -- light, sound, heat,
pressure, and proprioceptive feedbacks from muscle fibers.
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b. #2# CS modules controlling perceptions of Sensations, compiled
from intensities -- colors, shapes, edges, musical tones
c. #3# CS modules controlling perceptions of Configurations -particular static arrangements of sensations, such as objects and
musical chords
d. #4# CS modules controlling perceptions of Transitions -- changes
in level 1, 2, and 3 perceptions, for example the motion of an
object, or a musical chord transition
e. #5# Modules controlling perceptions of Events -- familiar
packages of lower-level perceptions
f. #6# Modules controlling perceptions of Relations -- between
lower-level perceptions -- such as above, below, near, or
following
g. #7# Modules controlling perceptions of Categories, to which
lower level perceptions belong, or don't
h. #8# Modules controlling perceptions of Sequences -- temporal
orders of lower level perceptions
i. #9# Modules controlling perceptions of Programs -- "structures
of tests and choice-points connecting sequences" or other lower
level perceptions. Quoting Powers: "To control a perception of a
program is to vary the lower level perceptions to keep the
program going right." An example is a routine for performing
long division. Level 9 is the level of rational thinking.
j. #10# Modules controlling perceptions of Principles: the reasons
why we have programs
k. #11# Modules controlling perceptions of Systems: organizations
of principles, from religions to bowling leagues
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#SLIDE 12#. Now that we understand how Control System Modules work
in a hierarchy, let’s look again at what the Input Function of each
Module does. A Configuration Level Input Function, for example, takes
in Sensation Level Perceptual Signals #CLICK01# and interprets them
as a bowl of fruit. #CLICK02# That is to say, from those perceptual
signals it infers that there is a bowl of fruit out there at a certain place
in the world.
#SLIDE 13#. So an Input Function is an inference engine,
#SLIDE 14#. and it might be more accurate to say that an Input Function
takes in perceptual signals from a lower level Module and delivers
inferential signals to the Comparator and Memory storage and to the
next higher level Module
#SLIDE 15#. – which in turn takes them in as perceptual signals.
We should realize, however, that the inferences made by the Control
Modules of an evolved brain, while pragmatically accurate, are not
necessarily the inferences that would be made by a team of scientists
studying the same environment.
We should also note that the evolved Control Modules can and often do
make inferences that could not be made by a scientific team today;
some of them, for example, can infer another animal’s intentions pretty
reliably, by reading his facial expression or his “body language”. But
about that more later.
To illustrate how the levels work together,
#SLIDE 16#. Suppose that the Configuration-level Module which is
inferring the fruit-bowl gets Googled #CLICK01# by a higher-level
Module, with an address signal eliciting PEAR from its memory. In
other words, it's being told "Control a perception -- that is, obtain and
maintain a perception -- of a pear."
Not close enough. #CLICK02# Your Configuration-level Module's
comparator sends out an error-signal #CLICK03# telling its output
function to address various Sensation-level Modules. But wait a minute.
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#SLIDE 17#. At this point we need to change our method of exposition,
to accommodate multiple interacting Modules on one screen. From
now on, we will identify a CS Module by a noun-phrase representing
the perception which that Module is currently controlling. #CLICK# For
example, the configuration-level Module now under study can be
identified simply as *PEAR*.
And from now on, a whole CS Module will be represented schematically by
a single box, containing a verbal, pictorial, or diagrammatic representation
of the perception which that Module controls. For example -#SLIDE 18#. With that in mind -#SLIDE 19#. CS Module PEAR's output-signals address several
sensation-level Modules, evoking from their several memories reference
signals to
#CLICK01# Perceive greenish-yellow, #AGAIN02# perceive pear-shape,
#AGAIN03# perceive pear-odor.
#CLICK04# The Sensation-level Modules send address signals to
Intensity-level Modules, evoking:
#CLICK05# Perceive eye-movement rightward and downward,
#AGAIN06# perceive nostrils expanding, #AGAIN07# perceive sniffing.
#SLIDE 20#. ---- and those Modules presumably modify the tensions in
muscles in eye, nose, lungs, neck, etc., adjusting those intensities
#CLICK01# until their input proprioceptions approximate their
respective internal reference signals.
#CLICK02# From the resulting visual and olfactory intensity perceptions,
the second level Modules infer sensations, compare them to the Pear
Odor, Shape, and Color sensation standards, adjust their output address
signals accordingly, #CLICK03# and send them on up to PEAR….
In a fraction of a second, after several dozen iterations, PEAR’s Input
Function infers that it is perceiving a pear, and all the Modules involved
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are, for the moment, at equilibrium. #CLICK04# No address signals are
going out, and you are focused on the pear.
So, in the hierarchy, each Module calls upon the ones below it to help it
control its assigned perception, by assigning them perceptions to control.
O.K. Now, how did you get confronted with that fruit-bowl, and why are
you seeking a perception of a pear?
#SLIDE 21#. In other words,
#SLIDE 22#. where did that PEAR-Google come from?
#CLICK01# It might well have come from a Transition-level Module
*REACHING FOR PEAR*, #CLICK02# Googled by an Event-level Module
*TAKING PEAR FROM BOWL*, #CLICK03# ultimately evoked by a
Program-level Module *GETTING AND EATING A PEAR* #CLICK04# -which utilizes many other subordinate Modules to get you into armslength of the fruit-bowl from wherever you were, and afterwards to get
you to proceed with the task of pear-ingestion.
#SLIDE 23#. To summarize our presentation of PCT so far:
Behavior, in general, can be understood as the control of perception.
#CLICK01#
The unit of behavior is the Control System (CS), #CLICK02# and even
the simplest activity requires the cooperative interaction of an
inordinate number of CSes. #CLICK03# CSes are indeed the individual
bricks of behavioral castles.
#SLIDE 24#. CSes are arrayed as Modules in interactive hierarchies.
#CLICK01# Each Module passes its inferences, about the world
outside the CS realm, to the next higher level in the form of
perceptual signals. #CLICK02# To control its incoming perceptions,
each CS Module uses lower-level Modules, by invoking reference
standards for them to control their perceptions to. #CLICK03#
The hierarchy provides behavioral reference standards for the entire
range of human activity. #CLICK04#
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Part Two
#SLIDE 25#.
#SLIDE 26#. Part Two. Evolution of the Input Function and Culture
Acquisition
We've said that Input Functions are, in effect, Inference Engines.
#CLICK01# So far the inferences we've discussed have been "empirical",
such as a scientist or other careful objective observer might make.
#CLICK02#
For example, a 3rd Level Input Function infers the presence of a bowl of fruit
from a set of perceptions from 2nd Level modules, or an Event Level Input
Function infers that a dog is chasing a cat from Transition Level perceptions
of a moving dog, a moving cat, and so forth. Another example would be a
prey animal's inferring that a predator was present.
These empirical inference engines no doubt evolved from simpler neural
networks half a billion years ago, and have been refined by natural selection
ever since.
But successful inferences may be trans-empirical or, in the vernacular,
judgmental. #CLICK03# …
#SLIDE 27#. As a very simple and early example, the prey animal might
infer that the predator has detected him, or not, before the predator
actually starts to attack. #CLICK01#
Continuing in that vein, the next evolutionary stage might be that the prey
infers whether or not the predator intends to attack. From input perceptions
of the predator's behavior, the prey is inferring the reference standard to
which the predator is controlling its perceptions. #CLICK02#
It would be interesting to survey the literature of ethology to learn what
species are capable of making inferences at each of these stages, and trying
to reconstruct their phylogeny. Certainly we can say that the ability to
guess, with increasing degrees of accuracy, what the other fellow was trying
to do, what he was "up to", has had great survival value. Besides
predator/prey relations, such ability has been very useful in interactions with
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conspecifics involving sex, fighting, dominance, and other social activities.
#CLICK03# We can also say that it was a long time coming, and that it has
been around for several dozen million years.
As it evolved, reference standard inference in the social realm eventually
enabled the recognition of individuals, empathy, so-called "theory of mind",
and the emergence of the sense of self, beginning perhaps 10 million years
ago.
More to the point of our discussion here, it enabled imitation. #CLICK04#...
#SLIDE 28#. Imitation entails perceiving the actions of another,
#CLICK01# inferring the reference standards being controlled to,
#CLICK02# recognizing those standards in one's own repertory,
#CLICK03# and evoking them to control one's own perceptions.
#CLICK04# In our own primate family line, that capability began to
evolve perhaps 10 million years ago, although it appears sporadically in
quite a few other taxonomic groups.
#SLIDE 29#. About two million years ago, the genes modifying input
functions to enable culture acquisition appeared and began to succeed.
#CLICK01# Our ancestors were then able not only to infer each
other's reference standards but actually to adopt them if they were not
already in repertory.
Since the ability to store inferences from perceptions was present long
before, it's rather puzzling that the emergence of culture acquisition took
so long. Storing a perception-inference of a satisfactory behavior of one's
own, during trial-and-error learning, goes way back in our phylogeny.
Apparently storing a perception-inference of a behavior of another animal
as one's own reference standard is a very different matter, but that's the
essence of culture acquisition, as we shall see.
Finally, and parenthetically, the language instinct may well have evolved as a
spectacular elaboration of the culture acquisition machinery. #CLICK02#
#SLIDE 30#. Individuals acquire culture largely through observational
learning.
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Descriptively, that means simply that an observer animal O observes the
behavior of a demonstrator animal D #CLICK01# and later exhibits similar
behavior, which he has never before exhibited. #CLICK02#
Without PCT, one is hard put to understand how culture-acquisition works,
because it's difficult to conceptualize how O can copy an entire behavior of
D, especially its motor elements, into his own nervous system. This difficulty
is exacerbated because O may simultaneously modify the behavior to suit his
own capabilities and circumstances. #CLICK03#
PCT nicely provides the mechanism for culture-acquisition, as per this
definition:
#SLIDE 31#. Observing the behavior of a demonstrator animal D,
#CLICK01# an observer animal O infers the reference standards to
which D is controlling her perceptions, #CLICK02# and stores the
inferred standards in the memory of one or more new CS Modules in
his own brain. Then O's newly acquired CS Modules control their input
perceptions by using existing and/or additional newly acquired lowerlevel Modules. #CLICK03#
To the extent that O's movements now seem to mimic D's, it is only because
they now have a common modular CS hierarchy.
In the vernacular, O observes D's behavior and figures out what she is trying
to do. Then he works out the means to that goal for himself.
Please note that the above discussion assumes that O does not already
possess all of the reference standards in question; if he does, he is not
acquiring culture from D. When he controls his perception to those
standards, he is simply imitating her.
In support of this formulation, I offer an interpretation of a recent
experiment involving imitation, and possibly culture acquisition, in dogs.
#SLIDE 32#. Very briefly, the Demonstrator D was an animal who had
been trained to pull on a stick with her paw to obtain a food reward.
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There were two groups of Observer dogs. When each O of Group 1
was exposed to D, D had a ball in her mouth.#CLICK01# Otherwise,
what the members of the two O-groups saw was the same: D pulling
on the stick with her paw and obtaining the
reward.#CLICK02#...#CLICK03#
The result was remarkable: Most of the Group 2 Os, who saw D without the
ball, pulled the stick, as she did, with their paws.#CLICK04# But the Group
1 Os, who saw her with the ball in her mouth, tended to use their mouths to
pull the stick!#CLICK05#...#CLICK06#
The experimenters called this an example of "inferential, selective imitation",
which indeed it is. I argue that PCT provides a mechanism for it and all
instances of imitation. In the case of Group 2, it may also exemplify cultureacquisition.
The Os in both groups inferred immediately that D was trying to move the
stick; i.e., that she was controlling a perception of Stick Moving.#CLICK07#
Pulling or Tugging with the Mouth is a well-established CS Module in dogs,
the standard Module invoked by an error signal from Stick Moving. As soon
as a Group 1 O saw that Stick Moving was the goal, the rest of the hierarchy
kicked in. #CLICK08# The ball in D's mouth was ignored, or perhaps not
even noticed, by most of the Group 1 Os. This is an apparent case of simple
imitation.
Only a few of the Group 2 Os, on the other hand, made that inferential leap.
It didn't make sense to the rest of them that D's perceptual goal was only
Stick Moving, so they inferred that D must be trying to pull the stick with her
paw; i.e., that she was controlling a perception of Pulling the Stick with the
Paw.#CLICK09# If a Group 2 O was familiar with that perception, that is if
he already had it stored as a reference standard, he invoked it and simply
imitated. If not, he stored Pulling the Stick with the Paw in a new Module as
a reference standard and proceeded to control his perception accordingly -- a
case of culture-acquisition.
#SLIDE 33#. As I said at the beginning of Part One, CSes are the units of
behavioral organization. The PCT-derived understanding of culture
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acquisition therefore solves, in my opinion, the problem of the
elemental units of culture. Control modules or reference standards so
acquired are what I once called “cultural instructions” and Richard
Dawkins renamed “memes”. #CLICK01# In fact, the only difference
between a meme and any other control module is the means by which
the carrying organism acquired it.
Equipped with a full complement of memes, encompassing every level
of the CS hierarchy, a people can build a whole culture, complete with
ethos, rituals, social organizations and structures, child-rearing
patterns, and artifacts.
In Part Three, upcoming, I will analyze a simple skill task and its
execution, using PCT tools. In doing so, I will demonstrate another
vital feature of PCT.
#SLIDE 34#.
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Part Three
#SLIDE 35#. The task to be analyzed was as follows. 12 young men
from the same cultural milieu were brought into a laboratory setting
one at a time. Each found himself in front of a table, on which was a
small sheet of plywood, on which were arranged two boards, two nails,
and a hammer, as shown.
#SLIDE 36#. Each subject heard an identical tape recording: "Please nail
the boards together in the form of an X." Filming commenced
immediately, and terminated about when the subject began to drive a
nail home. Every subject completed the task successfully.
The resulting film negatives were printed on long strips of paper and
subjected to frame by frame comparison,
#SLIDE 37#. whereby certain similarities and differences were noted in
the subjects' approach to the task.
Before presenting the PCT analysis, I will give you a run-through of all
twelve film-clips. Please note the following commonalities as you watch
the clips:
#SLIDE 38#.
1) All twelve subjects manipulate the boards into position before driving the
first nail; #CLICK01# that is, none start one or both nails first, although the
recorded voice command seems to suggest proceeding that way.
2) Some subjects form the X by drawing both boards into the workspace and
using one hand on each; #CLICK02# the others simply use one hand to turn
the top board.
3) All twelve subjects remove the hammer from the workspace as or before
they begin to handle boards. #CLICK03#
4) After forming the X, all twelve subjects exhibit the same nailing technique:
#CLICK04# hold the nail against the formed boards, tap the nail until it will
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stand alone, and then drive it home with more vigorous blows of the
hammer.
Now here are the clips. Running at half speed, they last a little under six
minutes.
#SLIDE 39#. {Wait for end of clip – Subject No. 4 is last}
OK, now let's undertake a PCT analysis of what we've just seen.
#SLIDE 40#.
At the system level, every subject is controlling a perception of being an
upper-division undergraduate, #CLICK01# enrolled in my introductory
anthropology course, #CLICK02# and voluntarily participating in an
experiment in cultural anthropology. #CLICK03#
At the level of principle, everyone is controlling for the value of conforming to
the experimenter/professor's wishes, #CLICK04# conveyed by the presented
display and the recorded voice, to nail the boards together in the form of an
X.
Each controls to the same program-level module: forming the boards into an
X and then nailing them together. #CLICK05#
And in the end, each follows the same pre-written program/meme for the
nailing process. #CLICK06#
It is in the execution of the "forming boards" part of the program that the
subjects appear to diverge.
In my previous analysis of these data, I made the mistake of assuming that
each variation in the final orientation of the X, and each variation in the way
the boards were manipulated to get there, was the outcome of controlling to
a specific meme. I think now that it makes more sense to regard those
variations as essentially fortuitous; that is, the subjects all controlled to a
rather hazy reference standard of one rectangular object lying at an angle
atop another. #CLICK07#
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And all the subjects began by controlling a perception of one or both boards
moving into the workspace. #CLICK08#
From there, each subject essentially ad libbed, choosing reference standards
and controlling his perceptions to them as he went along. Some were clearly
more adept than others, reflecting past experience; that is to say, they had
pre-acquired and honed CS Modules, and more ably accessed them when
needed.
In addition, the subjects varied in the extent to which they applied
imagination to the Forming Boards phase of the task. That is, in the extent
to which they rehearsed their behavior in their heads before executing it on
the ground.
The way PCT handles imagination is well illustrated by variations in the
handling of the hammer before its actual use in driving the nail. In every
case the subject moved the hammer as, or before, he drew one or more
boards closer to himself, into the workspace.
#SLIDE 41#. {Transition Slide}
#SLIDE 42#. It seems pretty obvious that everyone moved the hammer
to avoid perceiving a collision. As a base line, consider the case of
Subject No. 5, who shows no imagination. #CLICK01#
Before the recorded voice, the workspace is still. The Input Function of the
Moving Boards module is inferring the presence of the boards, #CLICK02#
the Input Function of the Removing Hammer module is inferring the
presence of the hammer, #CLICK03# and the Input Function of the Boards
Moving module is combining their perceptual signals to infer the presence of
the boards and hammer close together. #CLICK04#
Now comes the Address Signal to Boards Moving, #CLICK05# which in turn
addresses the memory of Moving Boards. #CLICK06# That Memory sends a
reference signal to the Comparator #CLICK07# which, perceiving that the
boards are not moving, sends an Error Signal to the Output Function,
#CLICK08# which addresses lower-level control modules down to muscles,
#CLICK09# and we observe the boards moving. #CLICK10 does
“environment” and starts the clip#
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... #CLICK11 stops the clip when the boards meet the hammer#
When Boards Moving infers that the boards are striking the hammer,
#CLICK12 # it acts to eliminate the disturbance by invoking Removing
Hammer, #CLICK13# and the situation is immediately resolved.
#CLICK14 when hammer has been removed #
In summary, Subject No. 5 moves the boards only when we observe the
boards actually striking the hammer. In the vernacular, he fails to anticipate
the collision and only reacts to it; he lacks imagination. In PCT terms, his
control modules are in control mode the whole time.
#SLIDE 43#. Now consider Subject No. 8, who does use imagination to
anticipate the boards striking the hammer. #CLICK01# Again, before
the voice command the workspace is still, the input sequences the only
ones active. #CLICK02#
When the address signal comes to No. 8's Boards Moving module,
#CLICK03# it too addresses the memory of Moving Boards, #CLICK04#
and that Memory propagates a reference signal. #CLICK05# But Subject
No. 8's Moving Boards module is in imagination mode. For the time being,
the signal is diverted across a shunt that carries it directly to the path of
Boards Moving's input perceptual signal. #CLICK06# The control sequence
down the hierarchy of modules to muscles, and the feedback sequence from
sensors back to Moving Boards and Boards Moving, are cut out of the loop.
So Moving Boards' reference standard becomes one of Boards Moving's input
perceptions.
Boards Moving therefore infers that the boards are striking the hammer, and
invokes Removing Hammer. #CLICK07# ...and we observe the hammer
being removed ... #CLICK08 stops movie when hammer is removed#.
Then the Moving Boards module switches from Imagination Mode to Control
Mode, #CLICK09 ... and we observe the boards moved and then formed and
nailed together
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#SLIDE 44#.
You probably noticed that several of the subjects, including No. 5 and No. 8,
once they have the hammer in hand keep it there, whereas others put it
down while they form the X with the boards, as if it hasn't occurred to them
that they'll need the hammer again immediately. #CLICK01# Those who
keep the hammer apparently run the whole task in imagination mode, at
least to the point of starting the nailing program, before beginning.
#CLICK02
It's not too much of a stretch to assert that all exercises of imagination and
anticipation are products of control modules acting in imagination mode.
#CLICK03# That would even including lower-case intelligent design or
creativity -- what Donald Campbell dubbed "evolutionary epistemology":
blind variation and selective retention inside the nervous system.
#CLICK04#
#SLIDE 45#.
#SLIDE 46#. Part Four. The Evolution of Cultural Features by means of
Natural Selection
In Part Two we showed how Input Functions of Control Modules may have
evolved as inference engines. Initially they were simply interpreters of
observable conditions. Later they became interpreters of others' intentions,
and finally they became acquirers of others' intentions, in other words culture
acquisition mechanisms.
#SLIDE 47#. This was all of course through genetic evolution; each of
these capabilities was built on the preceding ones, and each capability
was refined constantly, always by the mechanism of natural selection.
That means simply that genes which made more accurate and
otherwise useful input functions thereby enabled themselves to
propagate at the expense of competing genes, and eventually to
replace the latter.
In the case of culture acquisition engines, selection has clearly favored those
that made more faithful copies of the demonstrator's reference standards, for
exactly the same reasons that, starting millions of years before, selection
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favored mechanisms that copied genes faithfully. #CLICK01# If having a
cultural repertory is valuable, then being able to propagate that culture
accurately must also be valuable.
So one should not be terribly surprised that humans, particularly the very
young, are extremely adept at culture acquisition.
And the more accurate the copying, the more powerfully natural selection
can operate on that which is copied.
So memes which are better adapted to their environment will succeed at the
expense of those less well adapted, where "adapted" refers to the ability to
cooperate and compete with other memes in that environment. #CLICK02#
Memes controlling to which makes their carriers better able than others to
acquire resources, avoid predation and other dangers, form social bonds,
enjoy sexual opportunities, and so forth, will succeed. #CLICK03#
The operative word here is "better". We don't expect perfection from genetic
selection, far from it, and we shouldn't expect it from culture selection. But
selection for the better can, and has, produced some remarkable results.
#CLICK04#
Thank you for viewing “Perceptual Control Theory and the On-Going
Evolution of Culture”
END
20
Notes
(XX,YY means #SLIDEXX#,#CLICKYY#)
02,02 Dawkins 1976, 1982; Cloak 1975; Williams 1966
02,04 Powers 1973; for up-to-date information about PCT, see
http://www.perceptualcontroltheory.org/
04,00 Powers 1973: 57-81
04,01-14 Powers 1973: Figure 15-3, p. 221
11,00-11 Powers 2004: 135ff.
30,00-01 Bandura and Walters 1963
32,00-07 Range et al.
40,06 Cloak 1974/2007
43,05 Powers 1973: 222-6
44,03 Campbell 1960
References cited
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Bourbon, W.T., Copeland, K.E., Dyer, V.R., Harman, W.K. and Mosley, B.L. (1990). On the
Accuracy and Reliability of Predictions by Control System Theory. Perceptual and
Motor Skills 71: 1331-1338.
Campbell, D. T. (1960). Blind variation and selective retention in creative thought as in
other knowledge processes. Psychological Review 67: 380-400.
Cloak, F. T., Jr. (1974/2007). Cultural ethology experiment number one. Paper presented
at 73d Annual Meeting of American Anthropological Association, Mexico City.
Available (2007) as a narrated PowerPoint presentation from the author.
Cloak, F.T., Jr. (1975). Is a cultural ethology possible? Human Ecology 3: 161-182.
Dawkins, R. (1976). The Selfish Gene. Oxford University Press, Oxford.
Dawkins, R. (1982). The Extended Phenotype: The Gene as the Unit of Selection.
Freeman, Oxford.
Powers, W. T. (1973). Behavior: The Control of Perception, Aldine, Chicago.
Powers, W. T. (2004). Making Sense of Behavior: The Meaning of Control. New
Canaan, CT., Benchmark Publications.
Range, F., Z. Viranyi and L. Huber. (2007). Selective Imitation in Domestic Dogs. Current
Biology 17: 868–872
Williams, G. C. (1966). Adaptation and Natural Selection: A Critique of Some
Current Evolutionary Thought, Princeton University Press, Princeton, N.J.