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Posts Tagged ‘William T. Powers’

Please Do Not Disturb

When a control system is humming along, the gap between the desired and current states is so small that the frequency of command issuance by the Decision Maker component is essentially zero; all is well and goal attainment is on track. However, with the universe being as messy as it is, unseen and unpredictable “disturbances” can, and do, enter the system at any point of access to the structure.

CS plus disturbances

If the sensors and/or actuators can’t filter out the disturbances or are malfunctioning themselves, then true control of the production system may be lost. Perceptions and commands get distorted and the distance between goal attainment and “reality” will be perceived as shorter or longer than they are. D’oh! I hate when that happens.

Who’s Controlling The Controller?

September 9, 2013 4 comments

The figure below models a centralized control system in accordance with Bill Powers’ Perceptual Control Theory (PCT).

CS-No Disturbances

Given 1: a goal to achieve, and 2: the current perceived state of the production system, the decision-making apparatus issues commands it presumes will (in a timely fashion) narrow the gap between the desired goal and the current system state.

But wait! Where does the goal come from, or, in cybernetics lingo, “who’s controlling the controller?” After all, the entity’s perceptions, commands, actions, and controlled quantity signals all have identifiable sources in the model. Why doesn’t the goal have a source? Why is it left dangling in an otherwise complete model?

Abstraction is selective ignorance – Andrew Koenig

Well, as Bill Clinton would say, “it depends“. In the case of an isolated system (if there actually is such a thing), the goal source is the same as the goal target: the decision-maker itself. Ahhhh, such freedom.

DM source tgt

On the other hand, if our little autonomous control system is embedded within a larger hierarchical control system, then the goal of the parent system decision maker takes precedence over the goal of the child decision maker. In the eyes of its parent, the child decision maker is the parent’s very own virtual production subsystem be-otch.

Usurped goals

To the extent that the parent and child decision maker’s goals align, the “real” production system at the bottom of the hierarchy will attempt to achieve the goal set by the parent decision maker. If they are misaligned, then unless the parent interfaces some of its own actuator and sensor resources directly to the real production system, the production system will continue to do the child decision maker’s bidding. The other option the parent system has is to evict its child decision maker subsystem from the premises and take direct control of the production system. D’oh! I hate when that happens.

No Middleman

It’s What We Do

March 18, 2013 1 comment

Error correction is what we are doing every instant of our lives – John Gall (The Systems Bible, P84)

OMG! Mr. Gall’s wisdom is spot on with William T. PowersPCT, which in effect states that:

We are a mysterious stacked aggregate of thousands of little control systems acting continuously on our environment in a manner which corrects errors between what we desire and what is. (BD00 via William Powers)

Need some dorky picture to visualize the undecipherable message? For context, try this one first:

CS Template

Next try this model of “us” (actually, anything that’s alive):

Stacked CS

When we go to sleep, our conscious mental control system building blocks temporarily go dormant. However, those at the periphery of the stack which directly penetrate the physical “us/environment” boundary never sleep – because the environment never sleeps. These unsung workhorse heroes at the bottom of the hierarchy symphonically collaborate to keep our blood pressure, temperature, breathing, heart beat, etc, within some preset genetic limits so that we can wake up the next morning! And the little buggers do this by…. continuously correcting for errors between what the bazillion “controlled variables” are and what they should be. Error correction is what we do.

Note that without nature’s loving cooperation in keeping the variations in the environment within the controllable limits of our little friends, we wouldn’t be here now – we wouldn’t have even “begun“. What a joyous and miraculous dance of life, no?

So, the next time someone asks you what you do for a living, tell them that you correct errors.

Man-Made And Person-Specific

January 9, 2013 Leave a comment

George Pransky taught (err, finally convinced) BD00 that all stress is man-made and person-specific. One person’s stress is another’s exhilaration. Nevertheless, environmental and situational factors probably do influence stress levels to some extent, no?

One would think that as one ascends the ladder in a hierarchical institution, his/her stress levels increase with rank, stature, and responsibility. This may be true in general, but there is some research evidence to the contrary:

No Sweat: Less Stress in Higher Ranks. “..this study suggests that those who manage others actually experience less stress — as measured through both biological and psychological assessments — than non-leaders. In fact, the stress level seems to go down as executives climb up the corporate ladder. Leaders with more authority, and more freedom to delegate day-to-day oversight, do better on this front than managers below them.”

The Whitehall Study. “The Whitehall cohort studies found a strong association between grade levels of civil servant employment and mortality rates from a range of causes. Men in the lowest grade (messengers, doorkeepers, etc.) had a mortality rate three times higher than that of men in the highest grade (administrators).”

It all comes down to “control“. If you believe (like BD00 does) in William T. Powers’ Perceptual Control Theory (that every living being is an aggregation of thousands of little control systems interconnected for the purpose of achieving prosperous survival), then the results make sense. It’s simply that people in the higher ranks have more “control” over their environment than those below them.

Stress Curves

Of course, take this post (along with all other BD00 posts) with a carafe of salt. He likes to make up stuff that confirms his UCB by carefully stitching together corroborating evidence while filtering out all disconfirmatory evidence. But wait! You do that too, no?

Every man, wherever he goes, is encompassed by a cloud of comforting convictions, which move with him like flies on a summer day. – Bertrand Russell

Command Vs. Control

August 22, 2012 1 comment

One of the acronyms in BD00’s evil glossary is “CCH“. It stands for “Command and Control Hierarchy” because BD00 thought that command and control were fused together like Forrest Gump‘s peas and carrots. However, In “Making Sense Of Behavior“, Bill Powers distinguishes between a command hierarchy and a control hierarchy in an interesting way.

In a command hierarchy, a command dictates a specific action (git ‘r done!). In a control hierarchy, a command is a reference signal that specifies the state in which a particular perception is desired to be at in a future point in time; a vision, if you will.

For example, a sequence controlling system doesn’t order the limbs to be in a particular configuration; it tells a lower level control system to perceive the limbs as being in a particular position, then another, then another. By receiving a less specific reference signal, the lower level position control system can compensate for unforeseen disturbances (wind, gravity, physical obstructions) without distracting the higher level control system from its purpose.

Bankrupt Models

August 17, 2012 1 comment

In his paper, “The Dispute Over Control Theory“, Bill Powers tries to clarify how Perceptual Control Theory (PCT) differs from the two main causal approaches to psychology: stimulus-response and command-response. In order to gain a deeper understanding of PCT, I’m gonna try to reproduce Bill’s argument in this post with my own words and pictures.

The figure below represents a PCT unit of behavioral organization, the Feedback Control System (FCS). An FCS is a closed loop with not one independent input (e.g. stimulus or command), but two. One input, the reference signal, is sourced from the output function of a higher level control unit(s). The second input, an amalgam of environmental disturbances, “invades” the loop from outside the organism.  Both inputs act on the closed loop as a whole and the purpose of the FCS is to continuously act on the environment (via muscular exertion) to maintain the perceptual signal as close to the reference signal as possible. As the reference changes, the behavior changes. As the disturbance changes, the behavior changes. Since action is behavior, the FCS exhibits behavior to control perception; behavior is the control of perception.

The figure below depicts models of the stimulus-response and command-response views in terms of the PCT FCS. The foremost feature to notice is that there is no loop in either model – it’s broken. The second major difference is that neither model has two inputs.

In the Stimulus-Response model, the linear, causal path of action is: Stimulus (a.k.a Disturbance) ->Organism->Behavior. In the Command-Response model, the linear, causal path of action is: Command (a.k.a Reference)->Organism->Behavior. Hence, the models can be reduced to these simple (and bankrupt) renderings of a dumb-ass organism totally under the control of “something in the external environment“:

So, you may ask: “How could our best and brightest minds in psychology and sociology gotten it so wrong for so long; and why don’t they embrace PCT to learn how living systems really tic?” It’s because they erroneously applied Newton’s linear cause-effect approach for the physics of inanimate objects to living beings and they’ve thoroughly crystallized their UCBs into cement bunkers.

When you push a rock, there is no internal resistance from the rock and Newton’s laws kick into action. When you push a human being, you’ll encounter internal resistance and Newton’s laws don’t apply – control theory applies.

Compounding the difficulty has been a surprising tendency for scientists who are normally careful to know what they are talking about to leap to intuitive conclusions about the properties and capabilities of control systems, without first having become personally acquainted with the existing state of theart. If any criticism is warranted, it is for promulgating statements with an authoritative air without having verified personally that they are justified. – Bill Powers

D’oh! BD00 takes major offense at Bill’s last sentence.

From The Ground Up

August 11, 2012 4 comments

In developing their feedback control system-based models (see below) for exploring the nature of human behavior, both Bill Powers and Rudy Starkermann really did start from the ground up.

By “the ground up“, I mean that their theories started with the basic building blocks of the brain and nervous system. The diagram below shows examples of Powers’s and Starkermann’s underlying neuronal models.

Unlike classical Skinnerian “behaviorists“, whose theories are founded on more abstract, “black box”, empirical findings, BD00 believes that Bill and Rudy’s theories are much more closer to the “truth” (whatever the hell that may be) behind what motivates human behavior. What do you think?

The proper study of mankind is man – Alexander Pope

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