# On Purpose **URL:** \ **Category:** CSG1993\ **Created:** [January 2, 1993, 9:19pm UTC](http://discourse.iapct.org/t/on-purpose/7886 "1993-01-02T21:19:20Z")\ **Posts on this page:** 6\ **Page:** 1

**Author:** ![\_Gary\_A\_Cziko](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/_/3ab097/32.png) [@\_Gary\_A\_Cziko](http://discourse.iapct.org/u/_Gary_A_Cziko)\ **Post date:** [January 2, 1993, 9:19pm UTC](http://discourse.iapct.org/t/on-purpose/7886/1 "1993-01-02T21:19:20Z")

[from Gary Cziko 930102.1800 GMT] (STILL typed "92" first!) Rick Marken (930102.1200) warns Bill Powers: > If you don't write this book, Bill, I will! (Visions of a PBS > documentary are already starting to dance in my head). That was > a really incredible post. No fair! I was planning to write such a book after finishing \_Without Miracles\_. I was going to call it \_On Purpose\_ (I could then tell people that I was writing a book "on purpose"). Bill's perspective of animism to anti-animism to control gives a wonderful organizing framework for the book. But since the current book is taking me so long (when my wife keeps telling people "My husband has almost finished his book" they reply "He must be a slow reader") I will let Bill and Rick take the first crack. With the book should come a computer disk with Rick's computer demos and an appendix with "my" collection of manual demonstrations of control (mostly stolen from others). There should also be a videotape companion to the book. It would include both the computer and manual demonstrations of control. I've have just viewed such a video which is a companion to John Koza's \_Genetic programming\_ and it is a very effective way to demonstrate the algorithms he describes in the book. And just about everybody (in North America at least) seems to a videotape player these days. This would also give Rick a start on preparing his PBS special (see what you've started, Ed?).--Gary > **···** > > ------------------------------------------------------------------ > Gary A. Cziko Telephone: 217.333.8527 > Educational Psychology FAX: 217.244.7620 > University of Illinois E-mail: g-cziko@uiuc.edu > 1310 S. Sixth Street Radio: N9MJZ > 210 Education Building > Champaign, Illinois 61820-6990 > USA > ------------------------------------------------------------------ ---

**Author:** ![Charles\_W\_Tucker9](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/c/b4bc9f/32.png) [@Charles\_W\_Tucker9](http://discourse.iapct.org/u/Charles_W_Tucker9)\ **Post date:** [August 20, 2007, 5:32pm UTC](http://discourse.iapct.org/t/on-purpose/7886/2 "2007-08-20T17:32:28Z")

[From Chuck Tucker (08.20.2007 12.57 PM)] Bill said (on 8/20): "One of these days I'm going to design that experiment I've described before. Set up a two-person task in which both one person sees a display of movable objects, and the other sees the same display, but the objects are not movable. The "instructor" tries to tell the other person how to move the objects so as to match a configuration the instructor sees printed out on a sheet of paper. Example "Put the red circle between the blue square and the yellow triangle." Of course this could be done without a computer, using two sets of objects on tables with a screen between them. Maybe someone else will beat me to this." This reminds me of several pieces of research that may be related to your issue. The first was reported in the Frontline program several years ago (I think you wrote a piece on this to Bruce) on the issue of "Facilitated Communication" where the claim was made that autistic non-speaking children could write poetry and do math with the assistance of a communicator guiding their arm using a typewrite-like board. The study was set up with a board between the autistic child and a facilitator who was quite familiar with the child and they were shown pictures of objects (e.g., a shoe, a sandwich, a boat, etc.) that the child had seen and named before in the co-presence of the facilitator but in all these instances in this study the facilitator could not see what the child saw and visa-versa. In every instance (N=179) the child gave the name of the object that the facilitator saw and not what the child was shown. No statistics were necessary the results were 100%. The other study is the famous study by Sherif (Clark took Social Psychology from him at OU) on the "autokinetic effect" (this study is also related to Ash's study [the teacher of Stanley Milgram] on the length of lines) where the participant was asked to estimate the movement of a light in a dark room. In several of the studies the experimenter was the only other participant while in others their were several other participants. In most of the instances (not clear on the numbers here) the participant stated that the light moved consistent with what he was told by the other participants(some of Sherif's work is described in Clark's book, pp. 62-70). Of course, in all of the studies the light was stationary. Someone replicated this study (I can't recall his name) where the participant were told the light did not move and they reported no movement. I hope these may be helpful to you and others on CSGNET. Chuck ---

**Author:** ![Richard\_Marken](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/9fc348/32.png) [@Richard\_Marken](http://discourse.iapct.org/u/Richard_Marken)\ **Post date:** [September 11, 1996, 4:07pm UTC](http://discourse.iapct.org/t/on-purpose/7886/3 "1996-09-11T16:07:24Z")

[From Rick Marken (960911.0900)] Purpose n 1. something set up as an object or end to be attained 2. an action in course of execution (Webster's New Collegiate Dictionary, 1980). Bruce Abbott (960910.2100 EST) -- > I would prefer NOT to use "purpose" to refer to a reference signal; it seems > wrong to say that the purpose of my thermostat is 72 degrees Faherenheit. The HPCT reference signal seems to correspond exactly to the first dictionary definition of "purpose"; the reference signal is a specification that is "set up" (by another control system) as an object or end to be attained. By this definition, the purpose of the thermostat is not a temperature (which is a controlled varable); it's the reference specification (implemented as the location of contacts) for the perceptual representation of the temperature (size of the bimetallic strip). The process of acting to bring the controlled variable to the reference level can also be called "purpose"; this would be consistent with the second dictionary definiton of the term; in this case "purpose" is the process - - an "action in course of execution" -- that produces the end to be attained. > the bird can also give itself a bath by means of those wings, but if that > were the purpose of wings then surely something more efficient would have > developed by now to serve that purpose So the "purpose" of wings is to allow flying rather than bathing because wings are so perfectly suited to flying rather than bathing? The "purpose" of an object, then, comes from how well suited it is to producing a particular result. Yet you say: "I would reject the idea that the purpose of the Moon is to cause tides" even though the Moon is well suited to producing this result. So there is more to saying that an object has a "purpose" than the fact that it is well suited to producing a particular result; it is also required that the object be "selected (and natural selection is a form of selection) for that purpose" -- ie. to produce that result. So, according to you and Simon, it seems that an object has a "purpose" if it is 1) well suited to producing a particular result and 2) this suitability was selected. These seem like pretty subjective criteria to me. How do I test to determine whether an object has purpose? Did the structures that we now call wings have a purpose before they could function as wings? Do objects have only one purpose at a time? Does the purpose of an object change suddenly or gradually? Did the structures that were to become wings suddenly have a new purpose as soon as they could be used to fly or did they gradually gain this purpose, overlapping perhaps with their previous purpose (if they had one), in evolutionary history? What is the scientific merit of your opinion that the wing has only one real "purpose" -- flight? In PCT, purpose is a testable phenomenon; we can objectively determine whether a system has a purpose (a reference for the state for a particular perceptual variable). The Test for the controlled variable is a test of purpose. This is the kind of purpose -- the conventionally agreed on referent of the word "purpose" -- that Simon and all other conventinoal psychologist shows no evidence of understanding. PCT is about this kind of purpose; that's why Simon has nothing to contribute to a PCT discussion of purpose -- except Nobel quality noise. RSM ---

**Author:** ![Bruce\_Abbott](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/b/ba8739/32.png) [@Bruce\_Abbott](http://discourse.iapct.org/u/Bruce_Abbott)\ **Post date:** [September 11, 1996, 10:08pm UTC](http://discourse.iapct.org/t/on-purpose/7886/4 "1996-09-11T22:08:53Z")

[From Bruce Abbott (960911.1705 EST)] > Rick Marken (960911.0900) -- > Purpose n 1. something set up as an object or end to be attained 2. an > action in course of execution (Webster's New Collegiate Dictionary, 1980). > The HPCT reference signal seems to correspond exactly to the first dictionary > definition of "purpose"; the reference signal is a specification that is "set > up" (by another control system) as an object or end to be attained. By this > definition, the purpose of the thermostat is not a temperature (which is a > controlled varable); it's the reference specification (implemented as the > location of contacts) for the perceptual representation of the temperature > (size of the bimetallic strip). Yes, the purpose is the end \_to be attained\_, not the end in and of itself. The purpose of the control system is not the value of the reference signal (e.g., 72 degrees F) but the end to be attained (i.e., bring the room temperature up to 72 degrees F and hold it there). > So, according to you and Simon, it seems that an object has a "purpose" if it > is 1) well suited to producing a particular result and 2) this suitability > was selected. These seem like pretty subjective criteria to me. How do I test > to determine whether an object has purpose? Did the structures that we now > call wings have a purpose before they could function as wings? Do objects > have only one purpose at a time? Does the purpose of an object change > suddenly or gradually? Did the structures that were to become wings suddenly > have a new purpose as soon as they could be used to fly or did they gradually > gain this purpose, overlapping perhaps with their previous purpose (if they > had one), in evolutionary history? What is the scientific merit of your > opinion that the wing has only one real "purpose" -- flight? I wish you wouldn't put words in my mouth. "What is the scientific merit of your opinion that the wing has only one real 'purpose' -- flight," you ask. Now this assumes that somewhere in my writing I have asserted that the wing has only one real purpose, doesn't it? What I did say is that the \_main\_ purposes of the wing are to provide lift, thrust, and control (during flight), and this is hardly the same thing as asserting that these are the \_only\_ purposes for which wings have evolved. For most artifacts created by human beings, we can ask the designer or other knowledgable person what the artifact is "for" (and there may be multiple answers); we discover the intention of its designer. We learn that screwdrivers are for driving screws and, if we are properly taught, that they should NOT be used for chizeling as this tends to damage the screwdriver and render it unsuitable for its intended purpose. But the screwdriver has characteristics that may suit it to other purposes (I might use a big one as a substitute tent stake, for example). If there are no knowledgable people around to provide a hint, I may have great difficulty discovering the purpose an artifact was designed to serve. I recently visited a museum in which several rather mysterious implements were on display and the visitor was invited to guess that they were for. I can tell you that I didn't have a clue. Still, if you told me what the purpose of each implement is, I could probably easily identify which features of the implement contribute to its ability to serve that purpose. Discovering the purpose from the characteristics of the artifact is much more difficult: a matter of inference. Archeologists often have great difficulty determining what purpose some artifact was designed to serve. But the fact is that the intended purpose of an artifact often can be inferred from its structure and organization. The job is even easier if you can see the object "at work," doing what it was designed to do. Now when we turn our attention to "natural" artifacts, I grant that there is no entity out there with any intentions, no designer and thus no purpose in the dictionary sense of intended use. Yet the structures that evolve still have that same character, AS IF they had been designed for a purpose. The reason they are as they are is that, over the course of evolution, these were the "solutions" that worked: that aided in the survival of the organism. If the bird's purpose (end to be attained) is to fly, it is able to do so only because its wings have been moulded over the course of evolution so as to exquisitely serve this purpose. They are not so well suited to other purposes for which the bird may employ them, such as beating off attackers. Objects whose characteristics have been shaped in this way can be described in ways that objects not so shaped cannot be. We can ask of them, what does this or that feature contribute to the function it serves, given the environment in which it must operate? In the control system, what is the function of the sensor, the comparator, the reference signal, the output mechanism? What is the function of the system as a whole? In objects not so shaped, their characteristics are merely their characteristics. They are as they are, and that's it. In biological organisms the characteristics have been so shaped. We can ask, what is skin for, and why is the skin of the seal backed up by a thick layer of blubber, whereas the skin of a dog is not? What is the end these features help these animals to attain, the purpose of these features? If you're going to insist that there is no scientific way to discover the answer, then you'll have to explain how biologists have been able to figure out those purposes for so many biological structures. Regards, Bruce ---

**Author:** ![Richard\_Marken1](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/r/ed8c4c/32.png) [@Richard\_Marken1](http://discourse.iapct.org/u/Richard_Marken1)\ **Post date:** [September 21, 1996, 10:08pm UTC](http://discourse.iapct.org/t/on-purpose/7886/5 "1996-09-21T22:08:11Z")

[From Rick Marken (960921.1500)] Bruce Abbott (960921.1145 EST) -- That was a wonderful quote from Kleiber; thanks for posting it. I think it shows clearly why talk of purpose in evolution and behavior gets so confused. Clearly, biologists don't know what purpose (control) is. For example, Kleiber says: > To seek a goal, however, implies the expectation of future events and > implies further that present actions are based on this expectation. PCT shows that this is incorrect. To seek a goal (carry out a purpose) implies no expectation of future events. It implies a perceptual representation of a current state of affairs, a (current) reference representation of the intended (goal) state of affairs, the ability to compare (measure the current difference between) these two variables and act to reduce this difference. Everything in this "goal seeking" process -- goal (reference), comparison, action, and result (perception) -- is happening simultaneously, in the present; the future is in the future. Kleiber's belief that goal seeking involves the "expectation of future events" seems to have led him, in the next sentence, to refer to goal seeking as "planning"; > Planning, in turn, requires a mind. So Kleiber seems to recognize that goal seeking (planning, purposeful behavior, the achievement of future ends) requires something that at least some animals (like himself) possess: a mind. So Kleiber must believe that goal seeking can be done by animals with minds. Nevertheless, he goes on to say: > In biology, however, teleological explanations are still used extensively. > > > Few biologists actually believe that animals and plants plan their own > > future, yet some, like Krebs (1954), feel that our understanding of an > animal, like our understanding of a machine, is improved by knowing its > > > purpose. So Kleiber seems to be contradicting himself -- at least, he is if he accepts the fact that he is an example of \_one\_ kind of animal with a mind. If he does accept this, then he must admit that teleological explanations are appropriate in at least \_some\_ cases; they are appropriate in cases where animals and plants actually \_do\_ plan (set a reference for) their own future. So Kleiber should be agreeing with Krebs: our understanding of some animals (the kind with a mind; the kind that seek goals) is, indeed, improved by knowing their purpose (what goals they "plan" to acheive).That's how PCT contributes to our understanding of animal behavior; it lets us determine an animal's purposes. Kleiber is sure right about one thing: > A design implies a designer, a planning mind. The problem, of course, is to determine when a particular state of the world is the result of design and when not. This is equivalent to knowing when a teleological explanation is appropriate and when it is not. Kleiber implies that teleological explanation is \_always\_ inappropriate. That attitude works against PCT. PCT says that teleological explanations are \_sometimes\_ appropriate; you just have to know \_when\_ they are appropriate. They are appropriate when the animal is producing results \_on purpose\_. PCT shows us how to tell when results are being produce on purpose. This is done by Testing to see whether some state of the world is or is not under control; whether a variable is in a particular state by accident (non-teleologically) or by design (teleologically). If one believes, as a \_matter of principle\_, that teleological explanation is always inappropriate, then one will be strongly inclined to reject the notion that PCT has anything worthwhile (let alone revolutionary) to contribute to a scientific understanding of the behavior living systems. There is no evidence that Darwinian "selection" is teleological; indeed, there is considerable evidence that it is not . For example, Darwinian selection seems to have made no effort to preserve the dinosaurs -- which had been around for millions of years -- after their numbers were reduced by a large but brief (in geological terms) disturbance. Similarly, there is no evidence that the behavior of most of the physical universe is teleological; cause-effect (in the form of Newton or Einstein's laws) seem to work fine. But there is strong evidence that the behavior of plants and animals is teleological; there is just no other way to explain the fact that these systems act to produce consistent results (tree trunks, houses, roads, cars, handshakes, kisses, etc) under highly variable circumstances. Best Rick ---

**Author:** ![Cote\_Remi](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/c/b3f665/32.png) [@Cote\_Remi](http://discourse.iapct.org/u/Cote_Remi)\ **Post date:** [September 23, 1996, 1:56am UTC](http://discourse.iapct.org/t/on-purpose/7886/6 "1996-09-23T01:56:23Z")

> From mr. Remi Cote 220996.2150 Kleiber talk about goal, Mr Powers was so specific in his theory to speak about reference...These are no synonym. Amybe don't have goal, they don't even have idea... but they live! > **···** > > \*\*\* > I wanted to tell to people on the list that I received > some more biblio, on equilibrium, second law of thermodynamic > and all those nice theory that I always thought I was too > dump to study, and now that I almost finish my thesis I am > confronted with these rampant deterministic vilain... > > So I will dig in this rich mud, try do digest a bit of it > and deliver my little baby on this list... It will be naive. > > Right now I have some interesting lead: > > Kugler and Turvey : \_Information, natural law and the self- > assembly of rythmic movement\_ > > Brooks: intelligence without reason 1991 > > Beer, Randall: A dynamical systems perspective on agent environement > interaction > > Stuff by Port R. & Gelder, Tim van: Mind as motion: explorations > in the dynamics of cognition. Cambridge, Mass.: Bradford MIT > > Thelen & Smith: \_A dynamic system Approach to the development > of cognition and action (1994) > > So I would like to thanks every one who help me in this. No it > is time to look at this material...If any of you have further > biblioindication, please send it to me: > > coteremi@ere.umontreal.ca > > I will report for a small review. All those Idea are close to HPCT > Some are very complex AI stuff, very technical, I won't report > that. I will mostly try to survey stuff concernig the upper layer > of HPCT, since that is where my modelisation is concerned with. > > Thank's REMI