Cultural-Historical Psychology
2020. Vol. 16, no. 2, 19–24
doi:10.17759/chp.2020160203
ISSN: 1816-5435 / 2224-8935 (online)
Cultural-Historical Activity Theory in the Framework of the “Functional Paradigm”
Abstract
General Information
Keywords: Cultural-historical activity theory (CHAT), regulation, self-regulation, autoregulation, cybernetics, existentialism, agency
Journal rubric: Problems of Cultural-Historical and Activity Psychology
Article type: scientific article
DOI: https://doi.org/10.17759/chp.2020160203
Funding. The study was funded by the Russian Science Foundation (RSCF), project # 16-18-10439 “The Systemic and Dynamic Analysis of the Activity Regulation”.
Acknowledgements. The author is grateful to Dr. Martin Lynch for helping in the language editing.
For citation: Leontiev D.A. Cultural-Historical Activity Theory in the Framework of the “Functional Paradigm”. Kul'turno-istoricheskaya psikhologiya = Cultural-Historical Psychology, 2020. Vol. 16, no. 2, pp. 19–24. DOI: 10.17759/chp.2020160203.
Full text
Introduction
The conceptual foundations and thesaurus of the Cultural-historical activity theory (CHAT) have been rather stable for decades; nevertheless, the foci of theoretical and empirical research shifted through its history from one to another problem and concept.
Vygotsky’s emphasis in the late 1920s—1930s was on the relation between individual mind and culture, on the issues of social and cultural mechanisms of shaping the human mind, on the problems of social and genetic psychology. Alexey N. Leontiev’s emphasis, during the early stages of the construction of activity theory in the late 1930s-1950s, was on the relation between activity and consciousness, on the issues of emerging consciousness and mind at large as a phenomenon of life, and on the problems of genetic, comparative and educational psychology. At the next stage, in the late 1950s—1970s, the emphasis shifted to the relations between activity, action, and operation, to the issues of activity structure and actual genesis, its executive mechanisms, to the problems of general and cognitive psychology.
Since the late 1970s a new shift of emphasis became visible, a shift toward the relations between activity and personality, to the issues of activity regulation and self-regulation and its ontogenetic development. Mikhail Kotik [22] and Oleg Tikhomirov [37] were among the first authors who introduced the ideas of regulation and self-regulation of object-related activity, including the thinking activity, to the context of activity theory; both authors stressed the role of personal meanings in regulatory processes. Somewhat later, Vyacheslav Ivannikov [18] launched his studies of voluntary activity regulation and a large group of authors ([2; 4; 7; 35; 36; 38]) contributed to the development of the theory of regulatory function of per - sonal meanings and meaning formations (see [24; 25] for details).
Probably the first scholar to have noticed this last shift and to have given it a conceptual shape was Bluma Zeigarnik, who published a paper entitled “Mediation and self-regulation in norm and pathology,” in which she characterized these two concepts as central ones for the given period of the activity theory approach ([43]; see
CC BY-NC also [44]). Her understanding of mediation as the stable modus of behavior in the mature person and her analysis of mediation distortions in different mental pathologies allowed her to proceed from activity regulation to selfregulation. The latter was conceived as the functional capacity of the whole person as an active agent, possessing multiple degrees of freedom regarding her activity.
Since then, the issues of regulation and self-regulation have become and still remain one of the central problem fields in CHAT. Specifically, this refers to cognitive processes (Boris M.Velichkovsky, Tatyana Kornilova, a.o.), motivation (Tamara Gordeeva, Ekaterina Patyaeva, a.o.), personality (D.Leontiev, Vadim Petrovsky a.o.), developmental psychology (Elena Smirnova, Katherine Polivanova a.o.), clinical psychology (Elena T. Sokolova, Elena Rasskazova a.o.), etc. The aim of this paper is to reveal the methodological status of the selfregulation approach as a part of what may be called the functional paradigm in the psychology of the 21st century, and highlight the place and the meaning of CHAT as an important part of this paradigm today.
Two competing paradigms
in modern psychology
Every meaning, including the meaning of a scientific theory, is defined by the context. Nowadays, the purity of a scientific school is not as important as it used to be some 50 years ago; on the contrary, a broader integration and broader contexts are required to see the meaning of our work better. The leaders of CHAT refer to the failure of essentialist thinking, focus on change, future- mindedness, probabilistic world, self-organization, and so on (e.g. [3]).
The classical psychology of the 20th century was based on the idea that individuals maintain a stable identity and are equal to themselves. This essentialist naturalistic explanatory paradigm proceeds from Aristotle, who stated that all bodies behave in accord with their underlying inherent nature; the point is to ‘cognize’ this nature that would allow us to predict all its individual manifestations.
James Bugental, prominent existential therapist, coined a metaphor of human life referring to a comic strip published in a newspaper: in the cartoon a small child is asking his parents whether we are alive or on tape. This is the main question, are we alive or on tape, because our experiences accumulated through our lifetime are being recorded on multiple tapes (today we would call them files or routines). Traits, drives, instincts are examples of such mental tapes. Recorded stereotyped responses can be reproduced in an appropriate situation. There is however an alternative which Bugental called being alive, which means doing something above and beyond the tapes. Being “alive” means the capacity of changing one’s action at any moment independent of the pre-existing patterns, the capacity of being different at any moment; this is something that cannot be recorded on tape [8].
Human personality refers to being alive rather than being on tape. Russian philosopher Pavel Florensky wrote about a hundred years ago that both human personality and human activity emerge through overcoming the logical law of identity, a being equal to itself [13, p. 80]. That means that personality emerges at the point at which a person stops being equal to themselves, stops being predictable and manageable.
True, the challenge of the 20th century was making sense of human psychological consistency, but the challenge and demand of the 21st century is making sense of human psychological change. The essentialist paradigm is no longer satisfactory and this became clear even by the middle of the last century. Gordon Allport [1] said that “personality is less a finished product than a transitive ptocess” (p. 19). George Kelly [20] introduced the concept of ontological acceleration, meaning by this that a human being changes, and this refers not only to ontogenetic or functional development but what changes is rather the human being as the species; our theories describe the human being of yesterday rather than the human being of today. Erich Fromm [15], having analyzed the problem of human nature, concluded that it consisted of the lack of any fixed nature. Recently Alexander Asmolov [2] stated that the target of psychology of our days is studying the changing person in the changing world (p. 365).
What can be the essence of this new paradigm, which is coming to replace the essentialist one? Jean-Paul Sartre phrased it in terms of his famous statement, “existence precedes essence” [34]. This means that there are no stable essences which would help to explain what is actually going on in the course of our existence. Alexey N. Leontiev [23] expressed the same idea in a somewhat different way, saying that all mental structures emerge and take shape through intentional activity. This statement had multiple empirical proofs. One more phrasing of the same fundamental idea belongs to the prominent physiologist, Nikolai Bernstein [5], who summarized his studies of human physiology, which he called the physiology of activity, in this way: “the task gives birth to the organ”.
All three approaches remained rather marginal through the 20th century; however, they seem to be most relevant for the new challenges of our century. More than this, the underlying principle of all three approaches is essentially the same, and it constitutes the most contemporary paradigm which may be called the functional explanatory paradigm (see [26]). It says: an individual resides in a permanent stream of changing relations to the world. These relations precede any sustainable mental structures of mind and personality and explain their emergence and change.
The functional explanatory paradigm
The word “functional” in this context was borrowed from Norbert Wiener [42], who used it to oppose his approach to behaviorism. Another prominent author, Ilya Prigogine (see [30]), preferred the word “pro- cessual” for the same idea. Functional, or processual views, are being thus opposed to essentialist, reactive, and dispositional views. For the former, the focus is on change. The functional explanatory paradigm says that all living creatures are in a constant motion toward a better state of affairs and evolve in the course of this motion, motivated by the challenge of adaptive change: improve or fail. We can speak of a functional sustainability as a special form of sustainability, which means keeping balance in movement, dynamic equilibrium rather than homeostasis, which is specific to the essen- tialist paradigm.
The functional paradigm consists of three confluent streams of thought in human sciences and the sciences of living processes. The first stream started with models of self-regulated activity in the biological sciences (Nikolai Bernstein, Pyotr Anokhin a.o) and continued in the post-war technical and information sciences as cybernetics and general systems theory (N. Wiener, W. Ross Ashby, L. von Bertalanffy a.o.); in our days it is being exemplified most pointedly by synergetics and the theory of complexity. The second stream was based on the existentialist ontology of being in the world (M. Heidegger, J.- P. Sartre, K. Jaspers, M. Bakhtin, L. Binswanger, P. Tillich, R. Laing, R. May, M. Mamardashvili, J. Bugental a.o.). CHAT, especially as developed in A.N. Leontiev’s activity theory approach, is the third stream (A.N. Leontiev, B. Zeigarnik, O. Tikhomirov, V. Zinchenko, A. Asmolov, V. Ivannikov, F. Vasilyuk a.o.).
Multiple parallels and mutual references can be found between these three approaches. The penetration of the self-regulation principles into CHAT has been briefly sketched in the introductory part of the paper. During the 1970s through 1990s, there were multiple theoretical and experimental studies in activity theory on emotional activity regulation, meaning-based regulation, volitional regulation, etc. The parallels between activity theory and existentialism have been noticed and explicated more than once, both from the side of existential phenomenology (Hans Thomae, Alfried Langle) and from the side of activity theory (A. Asmolov, E. Subbotsky, F. Vasilyuk), which explicitly stated this parallel. The parallels between cybernetics and systems theory are also documented. Ludwig von Berta- lanffy wrote that his views on the spontaneous activity of the living organism was a more realistic articulation of what existentialists tried to express in their very fuzzy language [6]. And Norbert Wiener [42] also stated says that he was basing his views on premises similar to those of the existentialists, being however more op - timistically disposed.
Autoregulation as an explanatory framework
The regulated process we are dealing with in psychology is activity that bridges an individual to the world. This embraces not only observable behavior but also mental activity without directly externalized products. In the most general formulation, life as the process developing between a living creature and the environment, or the world, should correspond to the way the creature exists and to the way the world exists. Vasily Davydov [11] called this double imperative the bilateral plasticity of human activity; in a sense, Freud’s [14] famous distinction between the pleasure principle and the reality principle refers to the same bilaterality. One is to ‘fit,’ both to reality and to oneself. If our activity fits to the world in line with the reality principle, we are realistic; if not, we are narcissists. If what we do corresponds to what we are, the activity is authentic, and if it does not, it is alienated (see also [28]).
The key idea of the autoregulation principle is that of the circular process which is directed by the perceived divergence between the desired and the actual state of affairs. Nikolai Bernstein was the first scholar who published this circular model as early as in 1929. Arguing with Ivan Pavlov’s reflex arc model, Bernstein introduced the idea of feedback reflecting the divergence between the actual and the desired, and proposed the model of a reflex circle instead of reflex arc (see [5]). His colleague, physiologist Pyotr Anokhin, published a competing, though essentially similar model of a functional system in 1934.. However, the works of both scholars became known worldwide much later, and it is Norbert Wiener who is usually referred to as the pioneer of the regulation paradigm (see [31]).
The structure of an autoregulated process, as suggested in all of the above-mentioned models, must include the following functional elements: 1. The process to be regulated. 2. The criteria of the desired. 3. The monitoring subsystem, providing the feedback on the actual course of the process. 4. The matching subsystem that evaluates the process of fitting to the criteria and eventually calls for corrections. 5. The correcting subsystem, implementing corrections of the process for better fitting the criteria. Autoregulation thus can be defined as the functional capacity of moving from less desirable outcomes to more desirable ones through ongoing monitoring and correcting of the current activity. The explanatory principle of regulation provides an alternative to the principle of linear determinism and the essentialist paradigm depicted above, which presumes that human activity is determined by the multiplication of stable internal (dispositional) and external (environmental) forces.
Jan Valsiner [39] reasonably argued for the term autoregulation instead of self-regulation, for the former does not imply a reference to an essence like the self. Often self-regulation is conceived as synonymous to selfcontrol over impulses, forceful imposing superordinate regulatory principles upon oneself. A broader meaning of the term seems however more insightful. The process may be autoregulated if monitoring and corrections are provided by the same system and the results of monitoring automatically cause necessary correcting actions. Autoregulation is an inalienable property of all living creatures, as well as of quasi-living artificial systems directed by goals or other superordinate criteria of the desirable. It suggests that the system strives to keep its functioning up to these criteria, and makes necessary corrections when the process diverges from the criteria.
Personality development as the growing
self-mastery: The person as autoregulated agent
An important aspect of the psychological explanation of autoregulation in terms of the functional paradigm is viewing personality development as progressive autoregulation [16], from the most basic capacity to control immediate impulses, whether bodily or behavioral, to the privilege of autodetermination, that is, being the origins of one’s action and decisions, capable of choosing the course of conduct based not only on situational feedback but also on field-independent higher motivations and value orientations [12; 33], including the capacity to reconstruct the highest regulatory instances at one’s own discretion [17].
The dichotomy of being autoregulated vs. being driven, conditioned, programmed, or a zombie has been articulated as long ago as in 1892 by Russian philosopher Vasily Rozanov: “Human life may be twofold: either unconscious, or conscious. By the former I mean life controlled by causes, by the latter life controlled by a goal” [32, p. 21]. These two regimes of living however are not just a matter of individual differences, but also a matter of intraindividual temporal fluctuations — whether we are determined and driven by “tapes”, or, whether we are directed to some goal and navigate the way toward it, staying alive, that is, capable of any change. “We can always oppose our own unpredictability to any surrounding uncertainty” (Alexander Asmolov, personal communication, 2019).
Rozanov’s philosophical statement, as well as Bugen- tal’s metaphor of tapes vs. living, has multiple analogues in psychological theories. A number of recent dual-system psychological models distinguish two types of human regulatory systems, one of them being unconscious and automatic and the other deliberate and self-controlled (e.g., “hot” and “cool” systems in [29]; “reflexive” and “reflective” systems in [9; 10]; “fast” and “slow” systems in [19]). Essentially, all of them are reincarnations of what Vygotsky offered in the early 1930s in terms of the distinction between higher and lower mental functions ([40]; see [21]). Lower functions are common to all animals, which act by means of inherent uncontrollable mechanisms. Higher functions develop over the course of our cultural development and take control over lower ones. Vygotsky emphasized the emerging and developing capacities of communication and self-reflection: “If we look at the significance of self-reflection for mental life at large, we shall see a profound difference between a nonreflective, naive personality structure, on the one side, and a reflective one, on the other” [41, p. 238].
The higher levels of organization in humans are thus deliberate and self-controlled ones. The develop - ment of agency and psychological mechanisms of selfdetermination refers to the emerging self-regulatory capacities. Humans widely vary in this capacity of self-governance or mastery over their own lives. An individual’s potential for autoregulation has been conceptualized in terms of personality potential [27], which refers to the system of stable personality vari - ables that account for the successful autoregulation in various domains of living, i.e., seeking and maintaining the way of acting that leads to the desired outcomes and changing the way of acting that diverges from them. The basic level of its development suggests ac - quiring the capacity of controlling one’s impulses and following non-biological urges; further development suggests the developmental transition from being determined to self-determination, from the competition of biological and social drives to the self-determined person investing their efforts into one’s own development. A mature human being becomes the agent of one’s own development above and beyond universal biological mechanisms and social institutions supporting this development and giving it a direction.
Conclusion
The message of the paper suggested that (1) cultural- historical activity theory at the present stage of its development is focused primarily on the issues of activity regulation and self-regulation (autoregulation); (2) its main tenet essentially coincides with those of existentialism and cybernetics and all three may be combined into the functional paradigm as a generalized approach to the explanation of living systems, specifically human beings, in their interaction with the environment (the world); the functional paradigm states the primacy of the process, actual functioning, activity, or existence, the absoluteness of uncertainty and changeability, and thus seems to be the most relevant paradigm for the challenges of our times; (3) individual differences and developmental succession as they refer to human psychological characteristics reflect the differences and progression of the mechanisms of autoregulation.
This paper presents only a brief argument in the most general heuristic formulation. Its explication and empirical support require more than a single study; its initial elaboration has been published in [27]. I hope that it will help in finding a relevant place for cultural-historical activity theory in the psychology of our days.
References
- Allport G.W. Becoming: Basic Considerations for a Psychology of Personality. New Haven: Yale University Press, 1956.
- Asmolov A.G. Psikhologiya lichnosti [The Psychology of personality]. Moscow: Moscow University Press, 1990. (In Russ.).
- Asmolov A.G. Vygotsky today: on the verge of non-classical psychology. New York, NY: Nova Science, 1998.
- Asmolov A.G., Bratus B.S. O nekotorykh perspektivakh issledovaniya smyslovykh obrazovanii lichnosti [On Some Prospect of Studying Meaning Formations in the Person]. Voprosy Psikhologii, 1979, no. 4, pp. 35—46. (In Russ.).
- Bernstein N.A. The Co-ordination and Regulation of Movements. Oxford: Pergamon Press, 1967.
- Bertalanffy Ludwig von. General system theory — A Critical Review. General Systems, 1962. 7, pp. 1—20.
- Bratus B.S. Anomalies of Personality. Orlando, FL: Paul Deutsch, 1990.
- Bugental J.F. Outcomes of an existential humanistic psychotherapy: A tribute to Rollo May. The Humanistic Psychologist, 1991. Vol.19, no. 1, pp. 2—9. DOI:10.1080/08873 267.1991.9986748
- Carver C.S., Johnson S.L., & Joormann J. Serotonergic function, two-mode models of self-regulation, and vulnerability to depression: What depression has in common with impulsive aggression. Psychological Bulletin, 2008. Vol. 134, pp. 912—943. DOI:10.1037/a0013740
- Carver C. S., Johnson S. L., Joormann J. Two-mode models of self-regulation and serotonergic functioning: Divergent manifestations of impulse and constraint. In Sokol B.W. (eds.), Self-regulation and Autonomy: Social and Developmental Dimensions of Human Conduct. (pp. 255— 278). New York, NY: Cambridge University Press, 2013. DOI:10.1017/CBO9781139152198.018
- Davydov V.V. Kategoriya deyatelnosti i psikhicheskogo otrazheniya v teorii A.N. Leontieva [The categories of activity and mental reflection in A.N. Leontiev’s theory]. Vestnik Moskovskogo universiteta. Ser. 14. Psikhologiya, 1979, no. 4, pp. 25—41. (In Russ.).
- De Charms R. Personal Causation. New York, NY: Academic Press, 1968.
- Florensky P.A. Stolp I utverzhdeniye istiny [The Pillar and the Affirmation of The truth]. In 2 vols. Moscow: Pravda, 1990. (In Russ.).
- Freud S. Beyond the Pleasure Principle. The Standard Edition of the Complete Psychological Works of Sigmund Freud, Volume XVIII (1920—1922): Beyond the Pleasure Principle, Group Psychology and Other Works, 1920, pp. 1—64. DOI:10.1037/11189-000
- Fromm E. The Heart of Man. Its Genius for Good and Evil. New York, NY: Harper & Row, 1964.
- Grouzet F.M.E., Sokol B.W. Muller U. Self— regulation and autonomy: An introduction. In B.W. Sokol, F.M.E. Grouzet, U. Muller (eds.) Self-regulation and Autonomy: Social and Developmental Dimensions of Human Conduct. (pp. 1—16). New York, NY: Cambridge University Press, 2013. DOI:10.1017/CBO9781139152198.003
- Harre R. Personal Being: a Theory for Individual Psychology. Oxford: Blackwell, 1983.
- Ivannikov V.A. Psikhologicheskie mekhanizmy volevoi regulatsii [Psychological Mechanisms of Volitional Regulation]. Moscow: Moscow University Press, 1991. (In Russ.).
- Kahneman D. Thinking, Fast and Slow. New York, NY: Farrar, Straus, Giroux, 2011.
- Kelly G. Clinical Psychology and Personality: the Selected Papers of George Kelly. Maher B. (ed.). New York, NY: Wiley, 1969.
- Kinnucan C.J.E., Kuebli J.E. Understanding explanatory talk through Vygotsky’s theory of self-regulation. In Sokol B.W. (eds.), Self-regulation and Autonomy: Social and Developmental Dimensions of Human Conduct. (pp. 231— 252). New York, NY: Cambridge University Press, 2013. DOI:10.1017/CBO9781139152198.016
- Kotik M.A. Samoregulatsiya i nadezhnost cheloveka-operatora [Self-regulation and the reliability of an operator]. Tallinn: Valgus, 1974. (In Russ.).
- Leontiev A.N. Problems of the Development of the Mind. Moscow: Progress Publishers, 1981. (Originally published in 1892).
- Leontiev D. Psikhologiya Smysla [The Psychology of Personal Meaning]. Moscow: Smysl, 1999. (In Russ.).
- Leontiev D. The Phenomenon of meaning: How can psychology make sense of it? In Wong P.T.P. (eds.), The Positive Psychology of Meaning and Spirituality. Abbotsford, BC: INPM Press, 2007, pp. 33—44.
- Leontiev D. Samoregulatsiya kak predmet izucheniya i kak obyasnitelnyi printsip [Self-regulation as an object of study and as an explanatory principle]. In Morosanova V.I. (ed.), Psychologiya samoregulatsii v XXI v. [The Psychology of Self-regulation in the 21st Century] (pp. 74—89). Saint Petersburg: Nestor-Istoria, 2011. (In Russ.).
- Leontiev D. (ed.), Lichnostnyi potentsial: struktura i diagnostika [Personality Potential: Structure and Diagnostics]. Moscow: Smysl, 2011. (In Russ.).
- Leontiev D. Why we do what we do: The variety of human regulations. In Leontiev D. (ed.), Motivation, Consciousness, and Self-regulation (pp. 93—103). New York, NY: Nova Science Publishers, 2012.
- Metcalfe J., Mischel W. A hot/cool-system analysis of delay of gratification: Dynamics of willpower. Psychological Review, 1999. Vol. 106, no. 1, pp. 3—19. DOI:10.1037/0033-295X.106.1.3
- Prigogine I., Stengers I. Order out of Chaos: Man’s New Dialogue with Nature. Toronto: Bantam Bks, 1984.
- Rosenbluth A., Wiener N., Bigelow J. Behavior, Purpose and Teleology. Philosophy of Science, 1943. Vol. 10, pp. 18—24. DOI:10.1086/286788
- Rozanov V. Tsel’ chelovecheskoi zhizni [The goal of human life]. In Gavrushin N.K. (ed.), Smysl Zhizni: Antologiya [The Personal Meaning of Life: an Anthology]. Moscow: Progress-Kultura. 1994, pp. 19—64. (Originally published in 1892) (In Russ.).
- Ryan R.M., Deci E.L. Self-Determination Theory: Basic Psychological Needs in Motivation, Development, and Wellness. New York, NY: The Guilford Press, 2017. DOI:10.7202/1041847ar
- Sartre J.P. Existentialism and Humanism, trans. Philip Mairet. London: Methuen, 1948.
- Stolin V.V. Samosoznaniye lichnosti [The Self-consciousness of Personality]. Moscow: Moscow University Press, 1983. (In Russ.).
- Subbotsky E.V. Izucheniye u rebyonka smyslovykh obrazovaniy [The Study of Personal Meaning Structures in the Child]. Vestnik Moskovskogo universiteta, Ser. 14. Psikhologiya, 1977, no. 1, pp. 62—72. (In Russ.).
- Tikhomirov O.K. The Psychology of Thinking. Moscow: Progress Publishers, 1988.
- Vasilyuk F. The Psychology of Experiencing. Moscow: Progress Publishers, 1988.
- Valsiner J. Process Structure of Semiotic Mediation in Human Development. Human Development, 2001. Vol. 44, pp. 84—97. DOI:10.1159/000057048
- Vygotsky L.S. Istoriya razvitiya vysshikh psikhicheskikh funktsii [The history of the development of higher mental functions]. Sobraniye Sochineniy [Collected Works] (Vol. 3, pp. 6—328). Moscow, Russia: Pedagogika, 1983. (Originally published in 1931). (In Russ.).
- Vygotsky L.S. Sobranie Sochineniy [Collected Works], Vol. 4. Moscow, Russia: Pedagogika, 1984. (In Russ.).
- Wiener N. Cybernetics, or Control and Communication in the Animal and the Machine. New York, NY: The Technology Press and John Wiley & Sons, Inc. 1948. DOI:10.1063/1.3066516
- Zeigarnik B.V. Oposredstvovanie i samoregulatsiya v norme i patologii [Mediation and self-regulation in norm and pathology]. Vestnik Moskovskogo universitets, Ser. 14. Psikhologiya, 1981, no. 2, pp. 9—15. (In Russ.).
- Zeigarnik B.V., Kholmogorova A.B., Mazur E.S. Samoregulatsiya povedeniya v norme i patologii [Behaviour self-regulation in norm and pathology]. Psikhologicheskii Zhurnal, 1989. Vol. 10, no. 2, pp. 122—132. (In Russ.).
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