Cambridge, UK: Cambridge University Press, 2003, 370p. (incl. index) £47.50 ISBN 0521829062 (hbk); £17.99 ISBN 052153972 (pbk).
Cette recension est initialement parue dans European Journal of Social Theory, Mai 2005, vol.8, pp. 227–237, sous le titre : Book Review: The Archers: A Tale of Folk (Final Episode?).
Cette recension est initialement parue dans European Journal of Social Theory, Mai 2005, vol.8, pp. 227–237, sous le titre : Book Review: The Archers: A Tale of Folk (Final Episode?).
Elle présente un prolongement particulièrement original du réalisme critique dont Margaret Archer est la représentante principale en sociologie aujourd’hui.
With Structure, Agency and the Internal Conversation, Margaret S. Archer, the dean of the critical realist movement, has brought her theoretical reflections on culture, social structure and human agency to a successful conclusion with an empirical investigation of the mediatory process that spans the gap between the life-world and the system. Through in-depth interviews on the internal conversations that the respondents have with themselves, she illustrates how personal projects are formed and how they mediate the exercise of systemic constrains and enablements. The book under review constitutes the latest installment of “The Archers” – an impressive series of four books in which the morphogenetic approach to social theory is presented as a realist alternative to structuration theory. In the first two books, which can be considered as the polemic counterpart to Giddens’s triadic outline of structuration theory (in New Rules of Sociological Method, Central Problems in Social Theory and The Constitution of Society), Archer draws on David Lockwood’s Marxist functionalism and Roy Bhaskar’s critical realism to develop a sophisticated morphogenetic theory of the emergence, reproduction and transformation of cultural systems and social structures. In the last two books of the quartet, which can be considered as a protracted reply to Rom Harré’s Ways of Being (another trilogy, consisting of Social Being, Personal Being, Physical Being), she turns to the problem of human agency and analyses how human beings develop their personal and social identities as they pursue their “ultimate concerns” in more or less coherent and feasible life-projects.
The Emergence of Analytical Dualism
Margaret Archer has a problem – the problem of agency and structure. For more than twenty-five years now, she has been working her way through the issue of how to think culture, social structure and agency, and how to link them without reduction or “conflation”. To work out her own solution, she first needed to do some underlaboring work, however, and clear the rubble of her predecessors. In the first three volumes of the quartet, a massive offensive is launched against the reductive tendencies of contemporary social theory. Revisiting the mic/mac debates that have opposed individualists, collectivists and dialecticians since the 1950’s, the theorist from Warwick systematically tracked the conflationary tendencies and fiercely criticised rational choice, cultural studies and structuration theory for committing, one way or another, the “fallacy of conflation”. Methodological individualists and rational choice theorists like Max Weber, Karl Popper and Raymond Boudon, who solved the problem of structure and agency by conceiving of the former as an aggregate effect of individual actions, presented an overly voluntarist image of society and were guilty of “upwards conflation”. If individualists explain society (away) as a repetition of individual actions, culturalists and structuralists like Emile Durkheim, Talcott Parsons or Louis Althusser tend to conceive individual actions as mere emanations of social structures. They commit the fallacy of reification and are culpable of “downwards conflation”. Structurationists like Peter Berger and Thomas Luckmann, Anthony Giddens or Pierre Bourdieu, who see agency and structure as being dialectically implicated and mutually constitutive of each other, commit the error of “central conflation”. Instead of linking agency to structure, they are sinking the differences between both, with the result that their interplay can no longer be investigated.
Unrelentingly, book after book, Margaret Archer has exposed the conflationary tendencies of structuration theory. Despite her critique, Archer is not a negative thinker. Criticizing Giddens again and again, she advances an alternative theory of the constitution of society that is not only able to overcome the opposition between agency and structure, but also the defects of structuration theory. The major flaw of structuration theory is lodged in its rejection of ontological emergence and supervenience. In spite of the fact that Giddens allows that practices may result in important unintended consequences of action, his ontology of practices explicitly disavows the emergence of a relatively autonomous system possessing causal powers which are irreducible and temporally prior to the actions of individuals and groups. Professor Archer rebuffs the theorem of the duality of agency and structure, and opts instead for a stratified conception of reality that does not elide the difference between the systemic and the interactive strata of society, but acknowledges the relative autonomy of cultural systems and social structures, while analytically distinguishing them from the practices of the life-world that produce or transform them. This dualist strategy does not deny that the causal powers of cultural systems and social structures are always mediated through human agency (no agency : no system), but in order to elucidate the interplay between structure and agency, this strategy analytically separates both strata and keeps them constant. Thanks to this methodological trick, the dialectic comes to a standstill. As a result, the life-world and the system, as well as the relations between them, can be sequentially analyzed in slow motion as it were. When one does no longer assume that agency and structure or culture are mutually constitutive and operate at the same time, one can examine their interplay, probe if culture is more significant than structure (or vice versa), and tease out how their causal power is mediated through agency.
The Morphogenetic Quartet
Unlike Giddens, who is an eclectic thinker and a theoretical opportunist, Archer is more of a systematic theorist who carefully crafts out a series of fundamental concepts (e.g. analytical dualism, the morphogenetic sequence, the stratification of society and agency), and resolutely sticks to them. Wary of fads and fashions, the grand lady of British social theory has developed her own distinctive approach through a theoretical synthesis that tightly integrates the concomitant complementarities of the morphogenetic systems theory of Walter Buckley, the functionalist Marxism of David Lockwood and the critical realism of Bhaskar into a unified morphogenetic social theory. Even if the idea of analytic dualism and the morphogenetic sequence were already twinned and put to good use in the Social Origins of Educational Systems (1979), an 800-page comparative analysis of educational policies in France, England, Russia and Denmark, it would nevertheless take another four books to fully spell out the details of the morphogenetic theory of social, cultural and personal change. Early on, during her stay at Bourdieu’s Centre for European Sociology in Paris, Archer had acquired the strong conviction that in order to properly analyze the emergence, reproduction and transformation of cultural systems and social structures, one should focus on the dynamics between the system and socio-cultural interactions. Borrowing some insights from Buckley’s cybernetic study of the feedback mechanisms of “deviation-amplification” that trigger systemic change, she decomposed those dynamics in a series of endless morphogenetic cycles of systemic conditioning, socio-cultural interaction and systemic elaboration whereby the particular configuration of the system (at T1) conditions the practices of the life-world (at T2), which aim to reproduce or transform the system and lead, eventually (at T3), to a new elaboration of the system, which will be contested and modified in a second cycle, and so forth.
During her Presidency of the ISA (1986-90), Margaret Archer expands the morphogenetic approach into a general theory of culture, structure and agency. In Culture and Agency (1988), the first and perhaps the best of the quartet (1988), she builds up a complex, yet powerful and elegant analytic model of cultural change that is heavily indebted to David Lockwood’s theoretical attempt to marry structural functionalism with conflict sociology. Following an exploration of all the possible permutations of ‘social integration’ and ‘systemic integration’, she explains the morphogenesis of the cultural system in terms of the disjunction between the relations of contradiction and complementarity between the ‘parts’ of the system on the one hand and the relations of cooperation and conflict between ‘people’ on the other. When the contradictions between the ideas of the cultural system mesh with the social conflicts of the life-world, morphogenesis ensues; in the opposite case, morphostasis is more likely.
If Culture and Agency (1988) can be considered as a brilliant attempt to develop Lockwood’s seminal article into a full blown post-structurationist theory of cultural change, Realist Social Theory (1995), its successor, draws in Bhaskar’s critical realism to give ontological depth to the morphogenetic theory. Once again, Archer demonstrates her admirable analytical skills, but now the morphogenetic model is elaborated to develop a robust account of the stratification of social structures. The result of this exercise is a complex and rather complicated analysis of the dynamic relations that obtain between cultural systems (logical relations between ideas), social structures (internal relations of the first, second and third order between positions) and human agents. Archer argues that cultural systems can influence social structures and vice versa, but they can only do so indirectly and mediately by structuring the situation of actions through constraints and enablements. The force of the latter depends, objectively, on the social position of the agents and, subjectively, on their projects, the two being linked to a certain extent by the ‘causality of the probable’ (Bourdieu) which adjusts projects to possibilities. As individuals and groups are acting in situations to defend their vested interests and to realize their projects, they reproduce or transform the structural and cultural conditions that impinge on them, but in this process they are themselves being transformed from involuntarily placed agents into social actors and individual persons (double morphogenesis).
Following the analysis of structural morphogenesis, Archer investigates the morphogenesis of agency in Being Human (2000), the third and most personal book of the quartet. In line with the main tenets of critical realism, she grants causal powers to agency, which cannot be deduced from, or reduced to, the causal powers of society or culture. In order to make sure that the actor is not swallowed up by society or engulfed by language, she develops a theory of human agency that foregrounds the non social aspects of humanity. Granting priority to practice over language and society, she develops a sequential account of nested identities in which selfhood emerges from consciousness, personal identity from selfhood, and social identity from personal identity. Countering Rom Harré’s constructivist account of the discursive self, Archer argues with Jean Piaget and Maurice Merleau-Ponty that, even before the acquisition of language and independently of it, the ‘differentiation’ of the self from the world occurs through the embodied engagement with the world. Once a continuous sense of the self is acquired in early childhood, the formation of personal identity sets in as a life long quest for authenticity. Following Charles Taylor and Harry Frankfurt, the realist theorist argues that we become who we are through reflexive deliberation about our ‘ultimate concerns’. What we care about most and what genuinely matters to us is what ultimately defines us qua person. Archer contends that we all necessarily have three concerns - physical well being, performative competence and self-worth -, and that it is through the internal conversations we have with ourselves that we actually order them, define our vision of the ‘good life’ and thereby acquire an authentic personal identity that is uniquely ours. While self-identity is the alpha and personal identity the omega of human life, social identity intervenes in the middle as a subset of personal identity that expresses who we are as persons in society. It is at this point of the road of self-development that the ‘linguistic turn’ is taken and the story of the morphogenesis of the individual agent into a social actor can be told (as a sub-story of the morphogenesis of structure). At first, the human being is a (Bourdieusian) agent who involuntarily occupies a social position that defines his or her life-chances. As she becomes aware of the interests she shares with other members of his or her class, the agent is transformed into a (Tourainean) corporate agent who transforms society in such a way that the agent, who by now became a social actor and a role-taker, can not only occupy and personify the social role she takes on, but also personalise it in accord with his or her ultimate concerns.
The Mediation of Meditation
Building further on the double morphogenesis of agency and structure, the last installment (so far) of the Archers is uniquely concerned with specifying how the causal power of social structures and cultural systems is mediated through agency. The main thesis of Structure, Agency and the Internal Conversation states that the reflexive deliberations through which the social agents spell out and order their ultimate concerns in an existential and personal project to which they commit themselves, take the form of an internal conversation. It is this meditation of the ruminating self that constitutes the mediatory mechanism which links the causal powers of structure to agency. Social structures and cultural systems exercise their causal powers by structuring the situation of action through constraints and enablements, but to the extent that the activation of those causal powers depends on the existential projects that the actors forge in foro interno (no projects : no constraints or enablements), actors can be said to actively mediate their own social and cultural conditionings. Reformulated in the terms of Bourdieu’s generative structuralism, we could say that the internal conversation intervenes in between the field and the habitus. As a result the reproduction of society becomes an accomplishment of the agents themselves. Actors are thus indeed determined, but only to the extent that they determine themselves.
The book is divided in two parts of equal length. A first one in which the theoretical argument of the internal conversation is worked out in and through an extended discussion with American pragmatism (James, Peirce and Mead), and a second, empirical, part which explores the nature and the forms of reflexive deliberations of agents. The analysis of the soundtrack of the internal conversation reveals three different modes of reflexivity, and three concomitant stances toward society that constitute as many responses of the agents to social conditioning.
Self-consciously reversing standard sociological accounts of the subject, Archer opens the theoretical part of the book with the affirmation that private life is a precondition of social life: ‘Were we humans not reflexive beings there could be no such thing as society’ (p.19). Before she can make her case against social constructivists, however, the distinguished social theorist first has to establish the existence of private life and rebut behaviorist and cognitivist accounts that seek to exorcise the ghost of introspection from the machine. By means of a detour through the analytic philosophy of the mind (not the Geist), she argues that one can hardly deny the existence of reflexive deliberations that take place inside the mind and that those are only accessible from the first-person perspective. In accord with Bhaskar’s critique of empiricism, she substitutes the causal criterion of existence for the perceptual one, and advances her main thesis: ‘Reflexive deliberations have causal powers, that is intrinsic ones which enable us to monitor and modify ourselves, and extrinsic ones which allow us to mediate and modify our societies’ (p.46).
Once the interiority, subjectivity and causal efficacy of our reflexive deliberations is demonstrated, the next step consists in showing that those introspective deliberations take the form of an internal dialogue in which we deliberate with ourselves about our ultimate concerns and forge our personal identity. To make the move from introspection to the internal conversation, the British social theorist studies American pragmatism and employs Peirce’s semiotic approach of the self to develop her own morphogenetic approach of intrasubjective communication. While Peirce is celebrated as the towering figure, James is considered as a minor transitional figure and Mead is slashed off as an externalist who spoils the legacy of Peirce by socializing and colonizing the self. In this triangular reading of pragmatism, James appears as the one who initially suggested that we observe and monitor ourselves not by looking inwards, but by “listening to ourselves”. He conceptualized thought as a monologue, however, and not as a dialogue in which we speak, listen and respond to ourselves. Peirce corrected this oversight and conceptualized the internal deliberations as “a dialogue between different phases of the ego” whereby the latter addresses its former self as a Me, and invokes its future self as a You. While the Ego critically surveys its habits and its ingrained dispositions of the past to respond in a pre-arranged manner to given circumstances, it projects itself into the future and imagines a counterfactual I as a future You that is capable of acting otherwise and to overcome thereby the repetitions of the past. Using once more the morphogenetic sequence, Archer formalises this internal conversation as an infinite repetition of a basic three-phasic process whereby the pre-existing self conditions the dialogical activities of the conversational I that shapes and elaborates the You of the future. Through those internal discussions with ourselves (“I says to myself says I” is a vernacular account of it), we make up our minds by questioning ourselves, clarifying our beliefs and our inclinations, diagnosing our situations, deliberating about our concerns and envisioning existential projects that define who we really are. ‘In everyday terms, we examine our social contexts, asking and answering ourselves (fallibly) about how we can best realize the concerns, which we determine ourselves, in circumstances that were not our own choosing’ (p. 133). The life-long internal discussion comes to a provisional closure when the different parts of the self reach an internal consensus about the projected course of action that best expresses the authentic identity of the subject, yet is also feasible in the light of given circumstances. In so far as those internal deliberations about the course of action articulate the ultimate concerns that define the personal identity of the subject and the objective circumstances that have to be taken into account if the project of a life is to succeed, the internal conversation effectively integrates subjective projects and objective circumstances in a workable modus vivendi that can be considered as the living link between structure and agency.
So far so good, were it not for George Herbert Mead. Although the model of the internal conversation between the I, the Me and the You that Archer has skillfully lifted out of a discussion with Peirce is reminiscent of the account of socialization that one finds in Mead, she nevertheless reconstructs his theory of identity through generalized role-taking as an over-socialized anti-theory of the mind that should be rejected at any price if one does not want to spoil the Peircean model of the internal conversation. In the space of a few pages (pp. 78-92), which I consider the weakest part of this otherwise remarkable book, Mead is assailed as an ‘uncompromising externalist’ and a ‘downwards conflationist’ who got it all wrong. His theory of the mind is so through and through social that there’s simply no place for interiority. The inner conversation he talks about is not a dialogue one has with oneself, but with society, just as his Me is really a We. The result is a theory of intersubjectivity that cannot conceive of the internal conversation as an intrapersonal one. Even if Mrs. Archer is right when she characterises symbolic interactionism as a theory of intersubjectivity, I think she rejects and neglects it to her own peril. Reversing the perspective, one could as well turn the tables on her and assess the morphogenetic theory of personal identity “from the standpoint of a social behaviorist”. Subsequently, one would have to make two points:
1) That her theory of the internal conversation is too much of an internal conversation. Mrs. Archer has not only missed the ‘linguistic turn’, but as a result she has also missed the connection with more hermeneutic theories of personal identity and authenticity that are quite similar to hers in intent. By underplaying intersubjectivity and language, she failed to analyze the internal conversation as a narration of the self and to realize that it is through self-narration of their life-stories that actors order their concerns and make their life coherent. Narration is what ‘emplots’ and directs the internal conversation. To properly understand how personal identity is formed, one has to understand that the internal conversation takes the form of a narration, while the narration itself has to be understood as a conversation that is intrasubjectively intersubjective: One has not only conversations with “oneself as another” (Ricœur), but also with “the other as oneself” (Mead). It is through an internal conversation with oneself that one communicates with the other. Even if one narrates one’s self, the other remains present as an “inner witness” of the personal identity to which I commit myself and for which I am morally accountable and ultimately responsible. In any case, I am convinced that Mrs. Archer would really benefit from a protracted dialogue with the work of moral philosophers like Paul Ricœur (Soi-même comme un autre) Charles Taylor (Sources of the Self) and Alessandro Ferrara (Reflective Authenticity). It would not only give more philosophical depth to the ethics of existence that she’s pursuing and connect her work to the community of moral philosophers, but at the same time it would also allow her to give a stronger sociological backing to the philosophical hermeneutics of the self.
2) That her theory neglects intersubjective communication, social movements and democracy. Even if the internal conversation is conceptualized as a causal power that transforms both agents and society, only half of the story is told in this book. Foregrounding the morphogenesis of individual agency, the morphogenesis of structure through collective action is hardly touched. The book is about the ethics of existence, but fails to address the politics of life. This is no accident, but follows logically from the excommunication of intersubjectivity. To move from ethics to politics, dialogues with our selves simply won’t do, although they are necessary. We need to talk to others, with others, about others and about society. To expand the limits of our mind and our life-world, we need to extend the community of communication and adopt the universalist point of view of the ‘generalized other’ so that we can criticize existing societies from the point of an alternative, more inclusive and more democratic society. That is what Mead had in mind and it is what Dewey is all about. If Mrs. Archer wants to think politics and bring in social movements into her analysis of social change, I think that she might do well to re-read Mind, Self and Society once again, but this time from back to front, as Jürgen Habermas and Hans Joas did when they extracted a theory of democracy from the last part of the book. This, I would like to suggest, might be a suitable topic for another book that would complete the investigations on the morphogenesis of agency and structure and close off the series with a theory of (new) social movements. In case a title is needed, I suggest: Structure, Agency and Communication: A Morphogenetic Theory of Social Movements.
In the second part of the book, Archer goes empirical and presents a theoretically informed analysis of the 500 pages of transcripts of the in depth interviews she had with twenty people from all walks of life (of Ambridge?) – from three teenage hairdressers, employed in the same salon, to a sixty five years missionary nun who recently returned from Latin America; from a former academic who became an antiquarian bookseller to two homeless youngsters encountered in sheltered accommodation. In the interviews subjects were presented with the notion of the internal conversation, which no one disavowed, and asked questions about their mental activities (planning, rehearsing, mulling over, deciding, etc.), their current concerns (what matters most to them: others, work, self-development, etc.) and their life-projects. Throughout the tone is right and the subjects are treated with due care and respect. The main finding of the research, which the theory had not foreseen, was that that people practice different modes of reflexivity, which are systematically related to ‘stances’ which they adopt towards society, and that those different stances mediate socio-cultural constraints and enablements in quite distinctive ways. Archer distinguishes essentially three modes of reflexivity and presents them in a moving portrait gallery of communicative, autonomous and metareflexives.
‘Communicative reflexives’ are extroverted chatterers (mostly women) whose internal conversations are almost immediately relayed by interpersonal ones. They think and talk. Although Archer doesn’t say so, they are in fact Meadians who mistrust their lone internal conversations and turn to ‘significant others’ in their immediate environment to talk things through and dialogically resolve their questions. Their priorities are clear; what they care most about is ‘definitely family and friends’. Voluntarily reducing their aspirations, none of the interviewees had ever conceived of projects that exceeded their contextual confines. Shunning objective enablements to social advancement, all of them reproduced their familial backgrounds and showed contentment with their lot. From a more theoretical point of view, they can be considered as ‘conservative Habermasians’ and ‘contented Bourdieusians’ who are guided by traditional action and strengthen the social integration of the life-world.
‘Autonomous reflexives’ are lone thinkers (mostly men) with independent minds whose internal reflections are primarily goal-oriented. They think and act. Work seems to be their primary concern and, unlike communicative reflexives, they subordinate their interpersonal relations to work and are not afraid to move away from their initial context. In fact, it appears that, early on in their life, they had articulated life projects that burst the bounds of their social environment. Keen to act on social enablements, they also know how to circumvent anticipated constraints to accomplish their own ends. From a more theoretical point of view, they can be regarded as methodological individualists with a sense for Rawlsian fairness who invest their lives in performative accomplishments and whose instrumental (zweckrationale) actions benefit the system and strengthen the integration of its components.
‘Metareflexives’ are idealists who critically reflect on their reflections (hence meta) and seem genuinely concerned about their concerns, which don’t quite mesh with their ultimate concern and which they cannot dovetail to their own satisfaction. They think and think. Their internal conversation is directed towards their selves. Preoccupied with their selves (or perhaps I should say with their ‘souls’), they seek self-knowledge and practice self-critique for the sake of self-improvement and self-realization. Driven by a personal mission, they also criticize their environment and find them invariably wanting. As no available context ever satisfies their requirements, they are contextually unsettled and continuously on the move (even across continents), searching for a new job, a new career, a new life, a new self. As they cannot be bought off by inducements and are willing to pay the price of downwards mobility to realize their ideals, they are immune to constraints and enablements. From the point of view of social theory, those social utopians who act in a value-rational (wertrationale) fashion appear as authentic Habermasian Meadians who are always critically judging themselves and their societies from the point of view of another self (the ‘generalized other’) and another society (the ‘rational society’). However, as Archer would not agree with my reading of Mead, they might as well be described as the real Archerians (or in case she revises her interpretation of Mead, perhaps, as ‘archi-Meadians’).
Finally, next to and in between the communicative, the autonomous and the metareflexives, there are also ‘fractured reflexives’. These are individuals with broken lives whose powers of reflexivity have been either temporarily suspended as they are moving from one mode of reflexivity to another or even impeded all together, as is the case with poor Jason, a homeless delinquent whose subjectivity appears to have been arrested as a result of heavy drug use. Either way, reflexivity does not work for them. The more they think and talk to themselves, the more they get emotionally distressed and cognitively disorientated. Unlike full reflexives, fractured reflexives have no real projects and no strict personal identity either. As their internal deliberations do no allow them to deal successfully with their situations, they are ‘passive agents’ who are at the mercy of their social environment, which affects them from without as a pseudo-natural one. From a more theoretical point of view, they are the Humeans of the positivists and critical theorists who have forfeited control over their own life and can only passively register what happens to them. Alienated and reified into things, they are the people to which things ‘simply happen’.
Appropriately the tale of folk ends with a tribute to the metareflexives who show compassion and concern for the underdogs, the oppressed and the globally deprived, and refuse the status quo in the name of some cultural, religious or political ideal. Let us hope that they will be the heroes and heroines of the final installment of the Archers, dedicated to an empirical analysis of new social, cultural and religious movements.
Archer, M. (1979): Social Origins of Educational Systems. London: Sage.
Archer, M. (1988): Culture and Agency. The Place of Culture in Social Theory. Cambridge, UK: Cambridge University Press.
Archer, M. (1995): Realist Social Theory: The Morphogenetic Approach. Cambridge, UK: Cambridge University Press.
Archer, M. (2000): Being Human. The Problem of Agency. Cambridge, UK: Cambridge University Press.
Archer, M. (2003): Structure, Agency and the Internal Conversation. Cambridge, UK: Cambridge University Press.
Archer, M., Collier, A. and Porpora, D. (2004): Transcendence. Critical Realism and God. London: Routledge.
Ferrara, A. (1998): Reflective Authenticity: Rethinking the Project of Modernity. London: Routledge.
Giddens, A. (1976): New Rules of Sociological Method. London: Hutchinson.
Giddens, A. (1979): Central Problems in Social Theory. Action, Structure and Contradiction in Social Analysis. London: Macmillan
Giddens, A. (1984): The Constitution of Society. Outline of the Theory of Structuration. Cambridge, UK: Polity Press.
Harré, R. (1983): Personal Being. Oxford: Blackwell.
Harré, R.(1979) : Social Being. Oxford: Blackwell.
Harré, R. (1991): Physical Being. Oxford: Blackwell.
Ricœur, P. (1990) : Soi-même comme un autre. Paris : Seuil.
Taylor, C. (1989): Sources of the Self. The Making of Modern Identity. Cambridge, Mass.: Harvard University Press.
Frédéric Vandenberghe is Senior researcher at the University for Humanist Studies, The Netherlands, and Visiting Professor at the University of Brasília, Brazil.