Gordon Pask
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Andrew Gordon Speedie Pask (* June 28, 1928 in Derby, England; † March 28, 1996 London) was an English cybernetician and psychologist who made significant contributions to cybernetics, instructional psychology and educational technology.
Pask's most well known work was the development of Conversation Theory, which he intended to inform instructional design. He identified conditions required for concept sharing and described the learning styles holist, serialist, and their optimal mixture versatile. He proposed a rigorous model of analogy relations, and later developed Interactions of Actors Theory, an account of the processes supporting kinematic conversations bounded with beginnings and ends.
The memorial article which appeared in the The Independent newspaper (Scott, 1996), acknowledged Pask's unique approach to scholarship and life:
Gordon Pask was a rare man. He was an original; an eccentric in the best sense; gifted as a scientist, artist, lyricist. His peers in academic life have regularly acknowledged his genius. He had an exceptionally productive career (several books, over two hundred published papers). His many contributions are still being assimilated in psychology, educational technology, cybernetics and systems science.
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[edit] Biography
After qualifying precociously as a Mining Engineer at Liverpool Polytechnic (now Liverpool John Moores University), Pask obtained an M.A. in Natural Sciences from Cambridge (1952) and a Ph. D. in Psychology from the University of London (1964). In 1956, he married Elizabeth Poole with whom he had two daughters.
Whilst professor of Educational Technology he obtained the first D.Sc. from the Open University. In 1995 he was awarded a Sc. D. from his alma mater, Downing College Cambridge. Pask held faculty positions at Brunel University, University of Illinois at Chicago, University of Illinois at Urbana-Champaign, University of Mexico, Concordia University, Georgia Institute of Technology, University of Oregon, Open University and University of Amsterdam.
Pask was chairman of the Cybernetics Society from 1976 to 1979, and a recipient of the Wiener medal. He advised the professional cybernetician to proceed in the manner of the consulting detective Sherlock Holmes.
Pask was active in the theatre and wrote a collection of short stories "Adventures with Professor Flaxman-Low" (narrated extract with notes) as a literary comment on his work. For many years he was Senior Tutor at the Architectural Association in London. He drew and painted and was a member of the Chelsea Arts Club and the Athenaeum Club.
[edit] Conversation Theory (CT)
Pask's Conversation Theory (Pask, 1975) is a cybernetic and dialectic framework that offers a model to explain the "construction of knowledge", or, as Pask preferred "knowing" (wishing to preserve both the dynamic/kinetic quality, and the necessity for there to be a "knower").
Conversation Theory describes interaction between two or more cognitive systems, such as a teacher and a student or distinct perspectives within one individual, and how they engage in a dialog over a given concept and identify differences in how they understand it. Through recursive interactions called "Conversation" their differences may be reduced until agreement--that is, agreement up to a point which Pask called "agreement over an understanding"--may be reached. A residue of the interaction may be captured as an "entailment mesh", an organized and publicly available collection of resultant knowledge, itself a major product of the theory as they afford many advantages over semantic nets and other, less formalized and non-experimentally based "representations of knowledge".
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| Lastly a formal analogy is shown where the derivations of the concept triples are indicated. The diamond shape denotes analogy and can exist between any three topics because of the shared meanings and differences. |
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The relation of one topic to another by an analogy can also be seen as a restriction on a mapping and a distinction to produce the second topic or concept.
From Conversation Theory Pask developed what he called a "Cognitive Reflector". This is a virtual machine for selecting and executing concepts or topics from an entailment mesh shared by at least a pair of participants. It features an external modelling facility on which agreement between, say, a teacher and pupil may be shown by reproducing public descriptions of behaviour (see Pask 1975). We see this in essay and report writing or the "practicals" of science teaching.
Lp was Pask's protolanguage which produced operators like Ap which concurrently executes, Con, the concept of a Topic, T to produce a Description, D. Thus:
Ap(Con(T)=> D(T), where => stands for produces.
A succinct account of these operators is presented in Pask(1996). Amongst many fascinating insights he points out three indexes are required for concurrent execution, two for parallel and one to designate a serial process. He subsumes this complexity by designating participants A, B etc.
In Commentary toward the end of Pask (1996) he states:
The form not the content of the theories (conversation theory and interactions of actors theory) return to and is congruent with the forms of physical theories; such as wave particle duality (the set theoretic unfoldment part of conversation theory is a radiation and its reception is the interpretation by the recipient of the descriptions so exchanged, and vice versa). The particle aspect is the recompilation by the listener of what a speaker is saying. Theories of many universes, one at least for each participant A and one to participant B- are bridged by analogy. As before this is the truth value of any interaction; the metaphor for which is culture itself.
[edit] Interactions of Actors Theory (IA)
As a means to describe the interdisciplinary nature of his work, Pask would make analogies to physical theories in the classic positivist enterprises of the social sciences. Pask sought to apply the axiomatic properties of agreement to produce a "sharp-valued" social science with precision comparable to the results of the hard sciences. It was out of this inclination that he would develop his Interactions of Actors Theory. Pask believed that no two concepts could be the same because of their different histories. He sometimes called this the "No Doppelgangers clause" - later stated as "Time is incommensurable for Actors".
In 1995 Pask stated what he called his Last Theorem: "Like concepts repel and unlike concepts attract". For ease of application Pask stated the differences and similarities of descriptions (the products of processes) were context and perspective dependent. In the last three years of his life Pask presented models based on Knot theory knots which described minimal persisting concepts. He interpreted these as acting as computing elements which exert repulsive forces in order to interact and persist in filling the space. The knots, links and braids of his entailment mesh models of concepts, which could include tangle-like processes seeking "tail-eating" closure, Pask called "tapestries".
His analysis proceeded with like seeming concepts repelling or unfolding but after a sufficient duration of interaction (he called this duration "faith") a pair of similar or like-seeming concepts will always produce a difference and thus an attraction. Amity (availability for interaction), respectability (observability), responsibility (able to respond to stimulus), unity (not uniformity) were necessary properties to produce agreement (or dependence) and agreement-to-disagree (or independence) when Actors interact. Concepts could be applied imperatively or permissively when a Petri (see Petri net) condition for synchronous transfer of meaningful information occurred. Extending his physical analogy Pask associated the interactions of thought generation with radiation : "operations generating thoughts and penetrating conceptual boundaries within participants, excite the concepts bounded as oscillators, which, in ridding themselves of this surplus excitation, produce radiation" (paragraph 84 Pask 1993).
In sum, IA supports the earlier kinematic Conversation Theory work where minimally two concurrent concepts were required to produce a non-trivial third. One distinction separated the similarity and difference of any pair in the minimum triple. However, his formal methods denied the competence of mathematics or digital serial and parallel processes to produce applicable descriptions because of their innate pathologies in locating the infinitessimals of dynamic equilibria (Stafford Beer's "Point of Calm"). He dismissed the digital computer as a kind of kinematic "magic lantern". He saw mechanical models as the future for the concurrent kinetic computers required to describe natural processes. He believed that this implied the need to extend quantum computing to emulate true field concurrency rather than the current von Neumann architecture.
Reviewing IA (Pask 1996) he said:
Interaction of actors has no specific beginning or end. It goes on forever. Since it does so it has very peculiar properties. Whereas a conversation is mapped (due to a possibility of obaining a vague kinematic, perhaps picture-frame image, of it, onto Newtonian time, precisely because it has a beginning and end), an interaction, in general, cannot be treated in this manner. Kinematics are inadequate to deal with life: we need kinetics. Even so as in the minimal case of a strict conversation we cannot construct the truth value, metaphor or analogy of A and B. The A, B differences are generalizations about a coalescence of concepts on the part of A and B; their commonality and coherence is the similarity. The difference (reiterated) is the differentiation of A and B (their agreements to disagree, their incoherences). Truth value in this case meaning the coherence between all of the interacting actors.
He added:
It is essential to postulate vectorial times (where components of the vectors are incommensurate) and furthermore times which interact with each other in the manner of Louis Kaufmann's knots and tangles.
In studying experimental Epistemology Pask produced a tool kit competent to analyse and criticise the teaching and application of knowledge from the law, social and system sciences to mathematics, physics and biology. In establishing the vacuity of invariance Pask was challenged with the invariance of atomic number. "Ah", he said "the atomic hypothesis". He rejected this instead preferring the infinite nature of waves.
Pask held that concurrence is a necessary condition for modeling brain functions and he remarked IA was meant to stand AI, Artificial Intelligence, on its head. Pask believed it was the job of cybernetics to compare and contrast. His IA theory showed how to do this. Heinz von Foerster called him the cybernetician's cybernetician.
[edit] A note on Hewitt's Actor model
The Hewitt, Bishop and Steiger approach concerns sequential processing and inter-process communication in digital, serial, kinematic computers. It is a parallel or pseudo-concurrent theory as is the theory of concurrency. See Concurrency (computer science). Pask's true field concurrent, kinetic processes can interrupt each other but without buffering delays or priority.
[edit] See also
[edit] External links
- Pask obituaries
- Pask archive
- Conversation theory
- Cybernetics Society biography: The foundations of Conversation Theory: Interactions of Actors Theory (IA)
- Quicktime videos of Dr Paul Pangaro teaching Cybernetics and Pask's Entailment Meshes at Stanford
- Quicktime clip of Pask on Entailment Meshes
- Pangaro's obituary in London Guardian
- Scott's obituary in London Independent
- Glanville's obituary for International Federation for Systems Research
[edit] References
Barnes, G. (1994) "Justice, Love and Wisdom" Medicinska Naklada, Zagreb ISBN 953-176-017-9.
Glanville, R. and Scott, B. (2001). “About Gordon Pask”, Special double issue of Kybernetes, Gordon Pask, Remembered and Celebrated, Part I, 30, 5/6, pp. 507-508.
Green, N. (2004). "Axioms from Interactions of Actors Theory", Kybernetes, 33, 9/10, pp.1433-1462.
Pangaro, P. (1987). An Examination and Confirmation of a Macro Theory of Conversations through a Realization of the Protologic Lp by Microscopic Simulation
Pask, G. (1961). An Approach to Cybernetics. Hutchinson.
Pask, G. (1975). Conversation, cognition and learning. New York: Elsevier.
Pask, G. (1975). The Cybernetics of Human Learning and Performance. Hutchinson.
Pask, G. (1976). Conversation Theory, Applications in Education and Epistemology. Elsevier.
Pask, G. (1981). Calculator Saturnalia, Or, Travels with a Calculator : A Compendium of Diversions & Improving Exercises for Ladies and Gentlemen with Ranulph Glanville and Mike Robinson. Wildwood.
Pask, G. (1982). Microman Living and growing with computers. with Susan Curran Macmillan.
Pask, G. (1993). Interactions of Actors (IA), Theory and Some Applications
Pask, G. (1996). Heinz von Foerster's Self-Organisation, the Progenitor of Conversation and Interaction Theories
Scott, B. (1996). Obituary for Professor Gordon Pask, The Independent.
Scott, B. (2001). Conversation Theory: a Dialogic, Constructivist Approach to Educational Technology, Cybernetics and Human Knowing, 8, 4, pp. 25-46.
Scott, B. (2001). Gordon Pask’s Contributions to Psychology, Kybernetes, 30, 7/8, pp. 891-901.
Scott, B. and Glanville G. (eds.) (2001). Special double issue of Kybernetes, Gordon Pask, Remembered and Celebrated, Part I, 30, 5/6.
Scott, B. and Glanville G. (eds.) (2001). Special double issue of Kybernetes, Gordon Pask, Remembered and Celebrated, Part II, 30, 7/8.
Categories: 1928 births | 1996 deaths | British psychologists | Educational psychologists | Cybernetics | Alumni of Liverpool John Moores University | Alumni of the University of Cambridge | Alumni of the University of London | Alumni of the Open University | Academics of the Open University | Academics of Brunel University
