Descartes’ Legacy: Intersubjective Reality, Intrasubjective Theory
Edward Fullbrook (edward.fullbrook@btinternet.com)

Elgar Companion to Economics and Philosophy, editors: John Davix, Alain Marciano and Jochen Runde. London: Elgar, 2004, pp.403-422. ISBN1 84064 964 X

The idea of intersubjectivity is the hypothesis that human consciousnesses are constitutionally interdependent, that, as unique human personalities, we form and reform ourselves, not in isolation, but rather in relation to and under the influence of other human subjects and institutions. Neither now nor in other recent eras is this a view likely to provoke wide controversy. So it is markedly strange that intersubjectivity, under any name, did not figure significantly in modern philosophy until the last century, did not, until recently, mediate in social theory between holistic and radically individualistic explanations, and to this day remains axiomatically banished from a mainstream economics founded on subjective value theory.¹

The origins of this banishment seem incompletely understood. Much has been written about how the desire to model economics after classical mechanics required the assumption of economic agents whose individual identities, like Newton’s atoms, are unchanging and, most especially, impervious to mutual influence. [Mirowski, 1989; Fullbrook, 1996, 1997] But from where did this unlikely idea about human beings come? And why, when it runs contrary to all known experience, have so many intelligent and educated people found it plausible? Does a philosophically grounded intersubjective alternative exist? Finding the answers to these questions is a prerequisite for advancing economics beyond the reign of the neoclassical model of homo economicus. This essay looks for answers in the histories of modern philosophy and social theory and their relations to economics. What follows is divided into three sections. The first explores the tradition of Western intrasubjective philosophy, the second traces the development of intersubjective philosophy and social theory, and the third, in the light of the first two, considers the strange case of economics.

Intrasubjective Philosophy

Prior to the Enlightenment, most people enjoyed religious certainty regarding their notion of self and of their place in the world. But from the Sixteenth Century onward, secularized conceptions undermined religious ones, depriving the latter of their self-evident status, and so destroying the certainty regarding self that had been a common birthright in the West for centuries. René Descartes (1696-1650) began his famous metaphysical deliberations (Discourse on Method, 1637; Mediations, 1641) at this historical crossroads. Plagued by existential despair – he felt that even his own existence fell within “the sphere of the doubtful” - the French philosopher resolved to overcome it by rediscovering – he knew not yet where – certainty.

For this quest Descartes invented a method which he explains as follows:

I thought it necessary . . . to reject as if utterly false anything in which I could discover the least grounds for doubt, so that I could find out if I was left with anything at all which was absolutely indubitable. [Discourse on Method, part IV]

Descartes counted as doubtable anything revealed by our senses, because sometimes they deceive us (as when a straight stick looks bent in water).

. . . how do I know that He [an all-powerful God] has not brought it to pass that there is no earth, no heaven, no extended body, no magnitude, no place, and that nevertheless they seem to me to exist just exactly as I now see them. [First Meditation, p. 18]

Descartes concluded that he did not and could not know these things for certain. Furthermore, this uncertainty and his methodological doubt extended to the existence of his own body.

I shall consider myself as having no hands, no eyes, no flesh, no blood, nor any senses, yet falsely believing myself to possess all these things . . . [First Meditation (Haldane an d Ross, p. 19)]

Having a body, Descartes concluded, was not part of his essential nature. In the end only his existence as an incorporeal thinking being withstood his program of radical doubt. “I am thinking, therefore I exist.” On the basis of this alleged disembodied subjective certainty, together with an argument for a perfect God, Descartes sought to re-establish “objective” knowledge. That he succeeded is debatable. What is not is that his presumption of subjective certainty became the foundation of modern philosophy.

Descartes may only have been seeking a way beyond an existential and epistemological impasse. But his solution offered a new conception of the human self, one that, in the centuries that followed, permeated, defined and structured intellectual pursuits including philosophy, social theory and economics, and, through these, shaped the thinking of the general populations of Western societies. By conceiving himself as disembodied, Descartes not only found the metaphysical certainty that he desired, but also initiated the idea of a thinker/observer who is completely detached, existing independently of time, place and other human beings, and therefore, like God, totally objective. “I am a substance”, he wrote in A Discourse on Method (Part IV), “the whole nature or essence of which is to think, and which for its existence does not need any place or depend on any material thing.” This phantom of perfect self-consciousness and independence was reified by succeeding generations to become the intellectual ideal of Western society, an ideal that academics came increasingly to believe they had attained.

British empiricism, contrary sometimes to popular belief, founded itself on Descartes’ notion of a completely autonomous self, separate from place, time, materiality and society, and therefore self-identical over time. True, John Locke (1632-1704) broke with Rationalism by declaring that all our ideas were derived from experience. (An Essay Concerning Human Understanding, 1690) But he saw knowledge as a product of reason working out the connections between those ideas, and he insisted upon Descartes’ phantom as the agent who carries out this process of reason. Locke made a distinction between “person” and “man”, and, by extension, between personal identity and a man’s identity. The identity of a man, he wrote, is “participation of the same continued life, by constantly fleeting particles of matter, in succession vitally united to the same organized body” (An Essay Concerning Human Understanding II. xxvii, 6). But the identity of a person is that of “a thinking intelligent being, that has reason, and reflection, and can consider itself as itself, the same thinking thing in different times and places”. (II. xxvii. 9) Locke’s thinker is not his concept of “man” but rather his Cartesian concept of “person”, who, out of ideas, creates knowledge independently of time, place and society, and who became for British philosophers, no less than for Continentals, their imaginary, ideal persona.

At times the Scottish philosopher David Hume (1711-1777) courted scandal by rejecting the notion that we know ourselves as simple, unified beings who are self-identical from one time to another. He offered his famous metaphor of the theatre and suggested that each of us “is nothing but a bundle or collection of different perceptions, which succeed each other with an inconceivable rapidity, and are in a perpetual flux and movement” [A Treatise of Human Nature, 1739-40, Book I, section VI]. But this outlook, so unflattering to members of his profession, failed to seduce them. Indeed, following the appearance of Immanuel Kant’s Critique of Pure Reason [1781], Hume’s unassuming assessment of the nature of a philosopher’s self disappeared from sight. By identifying Descartes’ disembodied God-like self with philosophers in particular, Kant offered his colleagues a view of themselves that too few since have been able to resist. He sought to show that philosophical knowledge can transcend the bounds of experience, and this required him to center the putative power of transcendence with philosophers themselves.

Through the centuries the inward-looking line of thought begun by Descartes became a worldly and pervasive force in society. The Cartesian view of human reality, both on the Continent and in Britain, shaped the way we think, especially the way we theorize, about all aspects of social and personal existence, including, as we shall see, the economic. Descartes’ disembodiment of the thinker created a conceptually unbridgeable gap between the observer and the observed, the knower and the known, the subject and the object, thereby ascribing to each individual two separate planes of existence, an inside and an outside: one where we are the observer, the knower and the subject, the other where we are the observed, the known and the object of thought and perception. Under this dualism the body came to be thought of as a mere capsule, with windows called sense organs, in which human consciousness, cut off from the immediacy of the world around it and forever secure from the possibility of intersubjectivity, lived. This led to the tradition of thinking of the “nature” of human beings abstractly, as outside and beyond society, thereby erasing the complex and ongoing development of human agents.

In some spheres the categorical denial of intersubjectivity continued through the Twentieth Century. Indeed, with the advent of the Analytical movement, Descartes’ disembodied philosopher reached new heights of godliness. Bertrand Russell, in The Problems of Philosophy (1912), effectively the movement’s manifesto, first sets out the agenda, then calls for the development of philosophers capable of realizing it. The job specifications do not fit everyone. For recruits, Russell wants only intellects capable of “true philosophic contemplation” who

will see as God might see, without a here and now, without hopes and fears, without the trammels of customary beliefs and traditional prejudices, calmly, dispassionately, in the sole and exclusive desire of knowledge – knowledge as impersonal, as purely contemplative, as it is possible for man to attain. Hence also the free intellect will value more the abstract and universal knowledge into which the accidents of private history do not enter, than the knowledge brought by the senses, and dependent, as such knowledge must be, upon an exclusive and personal point of view and a body whose sense-organs distort as much as they reveal. [Russell (1912) 1967, p. 93]

Faith in this atemporal, disembodied and, therefore, intrasubjective self, both as an ultimate unit of analysis and as constituting the accredited performing philosopher, underwrites the analytical tradition. It is especially conspicuous in the tradition’s considerations of “rationality”, as when John Rawls reveals the foundational presuppositions of his celebrated A Theory of Justice (1971).

The essential point is that we need an argument showing which principles, if any, free and equal rational persons would choose . . . My suggestion is that we think of the original position as the point of view from which noumenal selves see the world . . . The description of the original position interprets the point of view of the noumenal selves, . . . [Rawls 1971, pp. 255-6]

For philosophers, this notion that some individuals possess the means to “see as God might see”, to attain “the original position” so that their point of view should then outweigh and invalidate all others holds a powerful attraction, capable of seducing the best minds, even Bertrand Russell’s.

Intersubjective Philosophy and Social Theory

At the beginning of the Nineteenth Century, Georg Hegel (1770-1831) rebelled against the abstract universalism of the Enlightenment by turning the Cartesian subjective self inside out. He argued that history displays a determinate direction and process of development, powered by an evolving collective Mind of which individual minds are but the finite and historically determined parts. Hegel’s works include brilliant analyses of how individual consciousnesses depend on recognition from others and of how they are socially constructed, and also of how reason is a changing structure of consciousness rather than an eternal archetype. In the main, however, Hegel’s philosophy dissolves subjectivity into a collective whole. Under his system, individual subjects are not so much “inter” related as “sub” related to an historical, all-transcending and largely determinate totality. This, as explanation, reverses the direction of causation. Just as the atomistic Cartesian self underpins methodological individualism, the “Hegelian self”, and its related notion of an all-encompassing whole, provides the ontological foundation of methodological holism. For the realm of human affairs, Hegel, in effect, reversed the putative direction of causality between the whole and the parts.

Intersubjective philosophy, which, in its modern from, emerged only in the last century, occupies the ambiguous middle-ground between these Cartesian and Hegelian extremes. It conceives of the individual as neither wholly autonomous nor wholly dependent, as neither wholly closed nor wholly open. This intrinsic conceptual ambiguity of the intersubjective project accounts in part for its failure to develop as a well-defined philosophical movement. Unlike its atomistic and holistic rivals, intersubjective philosophy, including its social theory offshoots, does not have categorical certainty at its command with which to frame pontifical pronouncements. Even its origins, though recent, are obscure and a little confusing.

Although the phenomenological movement, as founded by the German philosopher Edmund Husserl (1859-1938) at the beginning of the last century, is generally recognized as the watershed in the growth of the intersubjective approach to philosophy, the crucial philosophical moves that made it possible date from the late 1900s. The first involved dusting off an old idea, one common to the Scholastics of the Middle Ages. Philosophers had not always believed that consciousness was a container in which a person could, like Descartes, find the their virgin self lurking in some obscure interior corner, or, like homo economicus, observe their inner self to discover the data needed to construct their consumer preference map. Descartes’ sharp separation of body and mind led inevitably to the distinction between external and inner perception (or Locke’s “sensation” and “reflection”) which, in turn, required the notion of consciousness as a space where things exist through time and can be inventoried and measured by some further entity that is never named. Today this seventeenth-century notion of consciousness remains, alas, the sole version of the truth in most of the world’s Economics departments. But in 1870s Vienna a very different notion of consciousness was advanced, one that conceives of consciousness not as a repository but as a relation. This is Franz Brentano’s theory of intentionality. [1874]

Brentano’s theory states that consciousness is always consciousness of something. Instead of regarding consciousness as a kind of receptacle holding perceptions, sense data and images, Brentano taught – and his students included Franz Kafka, Carl Stumpf, Sigmund Freud, Alexius Meinong, Christain von Ehrenfels, Edmund Husserl, Bertrand Russell, G. E. Moore, Max Scheler and Martin Heidegger – that consciousness is a relation that human beings have to objects, material and immaterial, including those real, imagined and remembered. [Honderich, 1995, p. 104] Every moment of consciousness has something of which it is conscious. Brentano’s conception of consciousness as a relation that a being has to other beings and kinds of being, rather than a separate area of being, renders nonsensical attempts to look inwards for the self or ego or, indeed, for consumer preferences. Instead this view implies that the self – or selves – is, like everything else known in the world, merely an object of consciousness and thus, given the flow of consciousness, continually open to reconstruction.

Brentano’s principle of intentionality has a further dimension disruptive of the traditional metaphysical order. It maintains that it is the objects themselves – the Coca Cola bottle, the bowl of chili, the juicy red apple -- which figure in acts of consciousness. This view contravenes philosophy’s empirical tradition, as well as the Cartesian branch of the continental tradition, which, as in Hume’s theatre analogy, tends to regard consciousness as an indirect and passive experience of the world. It is indirect because it holds that when one looks at the red apple, the actual apple is not the object of consciousness, but rather a likeness or picture of the apple which appears in one’s consciousness. Thus, this view regards perception as only indirectly of things in the world. The principle of intentionality changes all that. The redness and juiciness of the apple are no longer “sensations” but rather what is sensed; they are properties of the apple which consciousness intends, rather than elements of consciousness representative of those properties. Under this way of thinking, the world is seen as something through which a consciousness moves and intervenes, and interacts and transmutes with other consciousnesses and their creations.

The other great demolisher of the Cartesian myth of a stable, coherent, disembodied and atomistic self, and the person whom Edmund Husserl credited as “the father of phenomenology”, was Henri Bergson. Whereas Brentano focused on the nature of consciousness vis-à-vis the world, Bergson explored its and the self’s relation to time and to the body. Today Bergson appears as a paradoxical figure in the history of philosophy. Although little read in the last sixty years (notwithstanding his current revival), he has had immense influence, having been widely read, discussed and digested by other philosophers in his own lifetime (1859 – 1941).

Bergson’s ontological world differed fundamentally from his predecessors. His philosophical interest was in Becoming rather than Being and in concrete particulars rather than in abstract and universal forms. These philosophical predilections made for great and productive mischief when applied to the notion of the human subject. Although Bergson conceived of the self as unified, he attributed this property not to the existence of a continuing essence, but to an evolving life-history that could accommodate change in all aspects of one’s personal identity. He emphasized the openness of the human subject, its developmental nature and its possibility of indeterminate -- that is, real – choice. By working on the plane of living reality, Bergson deconstructed the stable and determinant self so loved by philosophers.

But Bergson’s demolition of the Cartesian self went much further. He also escaped from the traditional mind/body dualism, and did so without resorting to reductive materialism. The following brief passage, in which the perceptions and actions referred to are his own, encapsulates his central innovation.

. . . thus perceptions are born and actions made ready. My body is that which stands out as the center of the perceptions; my personality is the being to which these actions must be referred.” [(1896) 1991, p. 47]

Rather than regarding his body as something distinct from his self or “personality”, his body is him in so far as he is an active person. His body is the “center “ of the perceptions on the basis of which he chooses his bodily actions which, in turn, refer back to his self. His body, far from belonging to a distinct realm of being, is central to and inseparable from how he experiences himself and how he chooses himself. In short, his self is embodied. This placement of the subject visibly and vulnerably in-the-world, when coupled with the intentionality principle, gave rise to the notion of intersubjectivity.

Edmund Husserl brought together these advances by Brentano and Bergson and made “intersubjectivity” part of the philosopher’s lexicon. He recognized that for each of us the phenomenological status of the world is a reality shared with other human subjects. We are each integrally linked or embedded in this social reality, and the linkage is dynamic and diverse. Let me elaborate.

The mind’s embodiment means that the self exists “out there” as a natural and social entity, intersubjectively permeable and therefore only partially under our control. Daily existence brings us in contact with the Other, both individual and collective others who apprehend our bodies from perspectives different from our own. Thus, to comprehend one’s self as a worldly subject/object one needs to adopt the multifarious and shifting perspectives of others. Furthermore, all our social acts (and very few of our acts are not social) take place in preexisting and ever-changing fields of intersubjective meaning. Events are, wrote Husserl, “experienced by each perceiving subject in a preconstituted intersubjective field of experience, events in which several human subjects participate” [quoted in Petit 1999, p. 233] Our experiences, including those formative and reformative of our individual selves, take place inside intersubjective structures -- genders, races, languages, legends, histories, governments, fashions, genres, games, news, professions, families, romances, friendships, etc., etc. -- which we, as autonomous individuals, may modify but which are ontological prior to each of our individual subjectivities, selves, preferences, etc.. Nor do the complications of intersubjectivity for the constitution of our selves stop here. Our social embeddedness is kaleidoscopic. In the coming and going of everyday life, as well as in the pursuit of ambitions, we enter and leave, and simultaneously inhabit different intersubjective fields, micro and macro, and with diverse and changing sets of people, which exercise their different influences on who we are. Finally, the view that intersubjective consciousness is built into selfhood, that intersubjectivity is an integral aspect of the self as subject, means that the we-dimension is ontologically fundamental to human reality.

This broadly intersubjective conception of the human being, the intersubjective self, that emerged in twentieth-century philosophy carries us a very long way from Descartes’ notion of consciousness as a private and impenetrable walled-off sphere, wherein resides a pristine self that commands the certainty of definition and constancy through time to support the God-like vision of Russell, the linguistic atomism of the early Wittgenstein, the noumenal self of Rawls and the well-defined and stable preferences of the neoclassical economist.

The intersubjective alternative to the Enlightenment’s Cartesian subject moved philosophy out of the realm of pure logic and pure thought by linking it to the physical, social and cultural worlds, including the general flux of experience. As always with revolutions, this one had unintended and unanticipated consequences, the most important being that it provided the first adequate philosophical grounding for social theory.

It was no longer necessary for philosophical-grounded non-holistic social theory to regard human “nature” as outside or before society or a-historical and static. Instead the human subject was now conceived of as intrinsically ambiguous and variable, each individual uniquely situated or embedded in an ever-changing intersubjective world, partly self-defined, partly defined by their history of particular situations. According to intersubjective philosophy, writes Mark Poster:

Not only did the individual inject meaning into the world, but the world injected meaning into the individual, so that the individual was immediately social. Defined both by others and by himself, he was out there in the world, perceiving and being perceived through his body.” [Poster 1975, p. 148]

Of course, all this is only commonsense. But, as I have shown, it is a way of seeing the human world that completely contradicts the philosophical tradition set in motion by the Enlightenment. The intersubjective self stands far removed from the idea of the single and unified self or subject presupposed by analytical philosophy and neoclassical economics. Under the new way of thinking, one’s view of oneself is neither more real than nor exempt from the influence of the views that others hold of oneself. Rather than being a simple and given unity, or even a unity formed on the basis of logical entailment, one’s self is a synthesis requiring management, upkeep, investment, friends, perhaps even therapy.

Through phenomenology, the post-Cartesian and post-Hegelian upsurge established the irreducibility of intersubjective consciousness, and thereby the joint interdependence of the “I” and the “We”, of the individual and society, of the event and history, rather than the dependence of one on the other that theretofore had in the main characterized social philosophy and social theory. This re-conceptualization of the human being was potentially momentous to the human sciences, including economics. This is because every study of human behavior bases itself, explicitly or implicitly, on some conception or model of the human being, which then determines the scope, nature and often the conclusions of its inquiry. Intellectuals did not take long to see that the intersubjective perspective had the effect of opening up new frontiers of the phenomenal world to investigation and perhaps even to understanding. From the 1930s on, the influence of the intersubjective conceptual foundation spread through social thought in numerous directions. These included French Existentialism (especially Simone de Beauvoir, Maurice Merleau-Ponty, and Jean-Paul Sartre), European and American sociology, (first Max Scheler, Karl Mannheim and Alfred Schutz, later Norbert Elias, Erving Goffman, Maurice Natanson, Thomas Luckmann, Perter Berger and Pierre Bourdieu), ethnomethodology (Harold Garfinkel), psychiatry (R.D. Laing), the many-faceted Frankfurt School (especially Walter Benjamin, Max Horkheimer, Erich Fromm and Jurgen Habermas), and, of course, the later work of Ludwig Wittgenstein and his followers, which showed that intersubjective, not intrasubjective, experience is the foundation of language.

This account of the development of intersubjective social theory remains radically incomplete. There is another side, one pioneered by women and people of colour that is no less important, although traditionally, alas, omitted from accounts such as this one. Both atomistic and holistic social theories leave oppressed social/cultural groups out in the cold. Atomistic theory tells the oppressed that their predicament is their own fault, and holistic theory that it is due to macro forces beyond their influence. So for such groups to launch, prior to the developments described above, liberation movements grounded in social theory, they themselves had to intellectually pioneer a way though the intersubjective middle, one that included both upward and downward causation (social structures shaped by individuals and vice a versa), one that emphasized the social construction of individuals but also taught them both how to collectively reconstruct themselves as individuals and how to band together to manipulate and change macro forces and structures.

Whereas today academic social theory is predominately concerned with traditional white male reality – social class, socio-economic status and occupational ranking – it used to be exclusively so. But for social theorists who belonged to oppressed groups and who in consequence usually found themselves outside the academy, oppression was the central issue. It fell to them to theorize the relations between the races and between the sexes. Indeed, it was these men and women who linked social theory to questions of human emancipation and developed the intersubjective social analysis, especially intersubjective identity theory, that broke down the traditional “division between conceptions of the person and conceptions of people in society” [Elias 1978, p. 129], and that increasingly underpins today’s academic sociology.

Olympe de Gouges in France (The Declaration of the Rights of Woman and the Female Citizen, 1791) and Mary Wollstonecraft in England (A Vindication of the Rights of Woman,1792) argued that women were socially constructed according to cultural notions of “feminine” and that these structures could and should be changed. De Gouges paid the ultimate price for her cultural heresy and died on the guillotine. But her and Wollstonecraft’s ideas were amplified at the women’s rights convention held at Seneca Falls, New York, USA in 1848. Symbiotically, this important event coincided with the rise of the American anti-slavery movement. In 1845 Frederick Douglass, escaped slave and intellectual, published his influential autobiography with its narrative structured around the idea that observable differences between the races and the identities of their members are socially and economically constructed rather than natural or innate or intrasubjective.

By the end of the Nineteenth Century these intersubjective ideas were central to a growing body of African-American social thought, most notably in the work of the sociologist W. E. B. Du Bois. In 1903 Du Bois, who had studied under William James at Harvard and later at the University of Berlin, published The Souls of Black Folk. It includes a short passage that has been quoted hundreds if not thousands of times and that I am going to quote again because it has been so influential in the development of contemporary social theory. The African-American, writes Du Bois, lives in:

. . . a world which yields him no true self-consciousness, but only lets him see himself through the revelation of the other world. It is a peculiar sensation this double consciousness, this sense of always looking at one’s self though the eyes of others, of measuring one’s soul by the tape of a world that looks on in amused contempt and pity. One ever feels his twoness, -- an American, A Negro; two souls, two thoughts, two unreconciled strivings; two warring ideals in one dark body, . . . [Du Bois (1903) 1965, pp. 214-5)

Here, in a few words, Du Bois harnesses together a formidable and formative team of intersubjective concepts: the self permeated by the social world, the social construction of race, the social embeddedness of the individual self, embeddedness in contradictory positions resulting in multiple selves or identities, the subject-object dichotomy in social relations, embodiment and, of course, the Other.

But what does this have to do with economics? Well, consider Du Bois’ s next paragraph where he applies some of these concepts to understanding a situation of “two unreconciled strivings”.

The history of the American Negro is the history of strife, ---this longing to attain self-conscious manhood, to merge his double self into a better and true self. In this merging he wishes neither of the older selves to be lost. He would not Africanize America, for America has too much to teach the world and Africa. He would not bleach his Negro soul in a flood of white Americanism, for he knows that Negro blood has a message for the world. He simply wishes to make it possible for a man to be both a Negro and an American, without being cursed and spit upon by his fellows, without having the doors of Opportunity closed roughly in his face. [215]

But our perceptions of economic phenomena have become so conditioned by neoclassicism that the penny may still not have dropped. So consider yet another passage, this one first published in 2002 and whose author and source I will for the moment withhold.

. . . dispossessed races and classes face a Hobbesian choice. One possibility is to choose an identity that adapts to the dominant culture. But such an identity is adopted with the knowledge that full acceptance by members of the dominant culture is unlikely. Such a choice is also likely to be psychologically costly to oneself since it involves being someone “different”; family and friends, who are also outside the dominant culture are likely also to have negative attitudes toward a maverick who has adopted it. Thus individuals are likely to feel that they can never fully “pass.”

In the paragraph following this passage its author cites Du Bois’s The Souls of Black Folk, but, unfortunately, without suggesting any direct indebtedness. The author is George Akerlof, winner in 2001 of what is popularly known as the Nobel Prize for Economics, and the passage quoted is from the paper he delivered when accepting the prize. [Akerlof 2002, p. 427]

Economics

Akerlof has sought to show the role that intersubjectively determined group identities play in the distribution of income and in the shaping of economic agents. This project deserves every possible encouragement, but it is very far from being based on a new idea. A central thesis of Simone de Beauvoir’s The Second Sex and of the materialist school of feminism (Christine Delphy, Colette Guillaumin, Monique Wittig, Ann Oakley, . . .) is that gender derives in large part from economic relations, especially divisions of labor by sex, not only between occupations, but also between paid and unpaid labor. This feminist argument is an application of the older and more general hypothesis that situations of work, including training for them, entail intersubjective effects that radically shape and reshape individual and groups of workers. A century of neoclassical hegemony seems to have erased from the profession’s memory the fact that this hypothesis stood at the origins of modern economics and was fundamental to Adam Smith’s “principle of division of labour”. It is worth quoting Smith at length, if only to show that economists, in the beginning, neither denied intersubjective reality nor were maliciously disposed toward the great majority of humankind.

The difference of natural talents in different men is, in reality, much less than we are aware of; and the very different genius which appears to distinguish men of different professions, when grown up to maturity, is not upon many occasions so much the cause as the effect of the division of labour. The difference between the most dissimilar characters, between a philosopher [economist] and a common street porter, for example, seems to arise not so much from nature as from habit, custom, and education. When they came into the world, and for the first six or eight years of their existence, they were perhaps very much alike, and neither their parents nor play-fellows could perceive any remarkable difference. About that age, or soon after, they come to be employed in very different occupations. The difference of talents comes then to be taken notice of, and widens by degrees, till at last the vanity of the philosopher is willing to acknowledge scarce any resemblance. [Smith, 1776, Book One, Chapter III. (Smith 1979, p. 120) ]

It seems to have gone almost unnoticed that neoclassical economics turned Smith’s principle of division of labour upside down. Instead of the division of labour accounting for differences between individuals, the neoclassicists claim that the differences are already there and account for the kinds of jobs and positions in the work hierarchy that individuals and groups (e.g., races) occupy. The market, so goes their account, tends toward realizing the maximum efficient use of scarce resources, including their optimal development. Of course, it is not claimed that this story holds true in every case, but in the vast majority. This is neoclassicism’s central message: the “free” market system by and large deploys resources, especially human ones, in a manner that best develops and utilizes their capacity to generate output and then pays them the value of their marginal product. According to neoclassicism, the economic differences between adults are not, as Smith argued, due mainly to the way the market, for whatever reasons, discriminates between similarly endowed individuals, but rather to “the difference of natural talents”.

This fundamental disagreement between Smith and the neoclassicists stems from the even more fundamental one which this essay has been at pains to illuminate. In offering his principle of the division of labour, Smith assumes, like Du Bois and Beauvoir, that individual identities, and hence the differences between them, are primarily endogenous to the socio-economic process, that is, they are intersubjectively determined. He is not, of course, denying the existence of inherited differences, but rather accepting the fact that the human being is in large part a socio-economic creature, not only in its behaviour but also in its making and remaking. The neoclassicists, on the other hand, have postulated their axioms in the tradition of high Cartesianism. The economic agent is assumed -- and the whole logical superstructure of the neoclassical enterprise stands on this Cartesian assumption -- to enter into economic relations with other economic agents without being changed by them. Without this assumption, all of neoclassical economics’ additive functions across populations of agents are non-existent.

Neoclassicism’s hypothetical exogenizing of the economic agent resulted in changes in economics infinitely more fundamental than its abandonment of the labour theory of value. Firstly, it effectively walled-off the greater part of the realm of economic phenomena from scholarly and scientific enquiry. In the name of axiomatic certainty, which it mistook for science, economics turned its back on some awkward but central empirical realities. Secondly, this cognitive disaster led to a moral one. Its turning its back on all economics phenomena that are not intrasubjective, that do not conform to its Cartesian metaphysic, gave rise to a spurious naturalism and the unarticulated but culturally powerful line of racism and sexism that it logically entails. [Fullbrook 2001] As George Akerlof gently puts it, “Neoclassical theory suggests that poverty is the reflection of low initial endowments of human and nonhuman capital.” [Akerlof 2002, p. 412] Poverty, as we all know, is not distributed evenly between races and sexes. So, when it is said that poverty reflects the “low initial endowments” of the people suffering it, a statement is being made about natural differences between races and sexes.

Although the inculcation of such views in the young is deplorable, the impetus behind the creation of neoclassical economics 130 years ago seems to have been entirely innocent. It grew out of the marriage of two exceptionally powerful but rigidly limited strands of thought, the doctrine of the Cartesian or intrasubjective self, with which this essay has been preoccupied, and the doctrine of Newtonian atomism, whose importance to the neoclassical project has been widely recognized. But significantly the union of the Seventeenth Century’s most important metaphysical ideas did not take place for nearly 200 years. By then, the 1870s, the hegemony of both doctrines in their respective fields was waning. The challenge to the Cartesian self in philosophy and social theory already has been noted. Meanwhile, the development of thermodynamics and Maxwell’s magnetic theory meant that the atomistic reductionism of classical mechanics no longer reigned on the frontiers of physics. But not so in the public imagination. Here mechanics was still king, and science was science only to the extent that it mimicked the Newtonian model. William Stanley Jevons [1835-1882), co-founder of neoclassical economics, was not only drawing on his general training in the natural sciences, but also playing to the public galleries when in the preface to The Theory of Political Economy (1871) he wrote:

But as all the physical sciences have their basis more or less obviously in the general principles of mechanics, so all branches and divisions of economic science must be pervaded by certain general principles. It is to the investigation of such principles – to the tracing out of the mechanics of self-interest and utility, that this essay has been devoted. The establishment of such a theory is a necessary preliminary to any definite drafting of the superstructure of the aggregate science. [emphasis added] [Jevons 1970, p. 50]

Marie Léon Walras (1834-1910) begins and proceeds in the same vain in his Elements of Pure Economics (1874-77) Alluding to the role of force and velocity in mechanics, he says:

Similarly, . . . this pure theory of economics is a science which resembles the physico-mathematical sciences in every respect. This assertion is new and will seem strange; but I have just proved it to be true . . . [Walras 1984, p. 71]

Walras does not have just any mathematics in mind, but rather that of classical mechanics. In applying a mathematics to an empirical domain, the key question for the real scientist is always whether or not the structures described by the former are isomorphic to those found in the latter.

Today the question might never violate the thought processes of an economist trained in a priorism. But for Walras, trained as a mining engineer, this question would have been at the forefont of his mind. It is the “proof” of an isomorphism between the differential calculus of classical mechanics and the economic phenomena of the market place (and thus also between economic and mechanical phenomena, i.e., Jevon’s “mechanics of self-interest and utility”) that Walras sets out to demonstrate at the beginning of his treatise. As he well understood, everything that follows in his book depends on this “proof”. Of what does it consist?

Well, of course, nothing empirical. Like Descartes, but in the name of science rather than of philosophy, Walras chooses to proceed definitionally, slicing up the universe into realms and assigning them the properties that will yield him his desired “results”. We may, he says, “divide the facts of our universe into two categories”: “natural phenomena” and “human phenomena”, whose essential difference, he proclaims, is that whereas the former result from “blind and ineluctable forces”, the latter result from human will which is “self-conscious and independent” [Walras 1984, p. 61] By “human will” Walras means the wills of individuals. This is the crucial Cartesian point. It is these wills, as Walras repeats numerous times, which are proclaimed independent and thus intrasubjective. But whereas Descartes devised this arrangement to relieve his philosopher’s existential angst, Walras needs it to launch economics as “a physico-mathematical science like mechanics” [Walras 1984, p. 71] This Cartesian self is mandatory if economic relations between human personalities are to be imagined as isomorphic to those between Newtonian bodies, that is, interacting but without altering their individual identities. A scientifically legitimate application of the mathematics of classical mechanics to economic phenomena requires this property of atomism. Without it, the individual supply and demand functions are not additive, thereby leaving the market or aggregate supply and demand functions undefined and, indeed, putting market analysis beyond the scope of the theory. But the neoclassical project’s dependence on Cartesianism extends further. It also requires, as Walras emphasizes [pp. 61-2], Descartes’ notion of self-consciousness: “nothing is more easily or manifestly perceptible to me than my own mind.” [Descartes 1970, p. 75] Post-Freud, no aspect of Cartesianism appears sillier and more untrue than this one. Nonetheless, neoclassical economics requires the crystalline self-knowledge of the Cartesian self in order to generate its putative functions. Having purged itself of the intersubjective dimension, it has only the self-knowledge of subjects hermetically sealed from influence from other subjects and their institutions to which to appeal for its hypothetical data for its “mechanics of self-interest and utility”, for its “physico-mathematical science”.

In constructing his “proof”, Walras sketched an ontology that guaranteed, as he justly emphasized, the purity of his product. By eliminating the intersubjective, Walras created a make-believe world in which the social dimension of economic agency was decreed from existence. This sociopathic ontology has now dominated economics for over a century. In his back-of-the-envelope style, Walras explicitly defined its basic categories. It divides the entities of the universe “into two great classes: persons and things. Whoever is not conscious of itself and not master of itself is a thing.” [Walras 1984, p. 62] It “divide[s] the facts of our universe into two categories”: “natural phenomena” and “human phenomena”. [p. 61] The latter is the product of human wills that are “self-conscious and independent”. [p. 61] The “realm of human phenomena” consists of two and only two categories: “human actions in respect to natural forces”, e.g., mining, and “relations between persons and persons” [p. 63] whose wills or subjective identities are independent of one another.

As we have seen, in the beginning modern economics did not duck the complexities of economic reality. I do not know when and where its intersubjective tradition began, only that in Adam Smith it was in good heart. And the neoclassical project need not have changed that. Neoclassicism is neither a useless nor an inherently intolerant, anti-scientific undertaking. Pretending that economic agents are radically different from how they are offers one point of view, even if a narrow one, from which to study economic reality. But the pseudo-science and fundamentalism that was already salient in Walras and Jevons became dominant in neoclassicism and has continued to be so down to the present day. Instead of contributing to a body of knowledge, neoclassical economics became a mandatory viewpoint, insisting that in matters economic it offered the only way to the truth. The result has been “a triumph of ideology over science” [Stiglitz 2002b].

In the century since economics’ autistic turning many economists have tried, with varying degrees of influence, to effect its rehabilitation. Caroline Foley was the first off the mark. In 1893 she published in The Economic Journal a long and elegantly argued article titled “Fashion” [Foley, 1893; Fullbrook, 1998], which not only called for the re-expansion of economics’ conceptual framework so as to include intersubjective demand phenomena, but also pointed out that rising standards of living cause consumer demands to become ever less closely tied to biological needs so that intersubjective factors enter increasingly into demand determination. Late the following year Thorstein Veblen not only took up Foley’s challenge but also her approach when he published “The Economic Theory of Woman’s Dress”, launching in his middle-age the line of intersubjective analysis for which he is celebrated. [Veblen 1894] The whole institutionalist school to which Veblen’s work gave rise was committed to considering economic agents as social beings. In the United States in the 1920s the Institutionalists briefly threaten the neoclassical hegemony before rapidly loosing ground. Keynes’s General Theory (1936), as well as some more traditional business cycle theories, turned on aggregate intersubjective effects, and with the post-war rise of Keynesianism it appeared that economics might, not just on the margins but in the main, escape from its Cartesian prison. But once again it was not to be. Led by John Hicks and Paul Samuelson, the neoclassicists marketed an emasculated Keynesian analysis, one without intersubjective agents, and succeeded in turning back the clock. Even John Kenneth Galbraith, whose work added much to the intersubjective tradition, could not reverse or even halt the retrogression. By the end of the 1980s any economist expressing professional concern with the intersubjective dimension of economic reality risked being assigned to the outer reaches of heterogeneity.

But what about the rise of game theory? One might say that because game theory is explicitly about direct interactions between individuals, it is about intersubjectivity. Such reasoning, however, misses the central thrust of this essay. Classical mechanics is also explicitly about interactions between individuals and how their interactions change their behaviour. The criterion for intersubjectivity methodology is not whether or not interactions take place between human individuals but rather whether those interactions are conceptualized as sometimes changing those individuals’ subjective characteristics..

Does game theory conceptualize human agents as intersubjective? In the main, no. It describes how in game-like situations agents choose strategies given exogenously fixed utility functions which represent the agents’ subjectivities. (This is true even of Lewis 1969.) But what about “evolutionary” game theory (e.g., Samuelson, 2002)? Despite its name, this appears to be a dead-end for intersubjective analysis. A byproduct of evolutionary biology, where the “players” are species and genes, its novel feature is that it treats players as hard-wired with particular strategies and therefore without the freedom to change, not only their ends, but also their strategic means.

A more promising route for bringing game theory to bear on some subset of intersubjective economic phenomena is Thomas Schelling’s (1960) “coordination game” approach. André Orléan (2003), seeking to understand “the inter-subjective and self-referential dynamics” (p. 179) of stock markets, has used it to achieve what is in effect a formalization of Keynes’s famous beauty contest parable (1936). Drawing on Shiller 1991, Orléan shows how a group belief can emerge autonomously relative to the beliefs of the group’s individual members and them become part of those individuals’ belief systems.

But there is much more to understanding the role of intersubjectivity in economic reality than formalization, let alone game theory, can reveal. Recent years have witnessed, despite the surge in neoclassical fundamentalism, new beginnings and growing respectability for intersubjective economics. And the new interest is diverse, not only geographically but also in terms of research programmes and topics: in France the French Intersubjectivists [Aglietta and Orléan 2002; Dupuy 1989, 1991, 2002; Levy 2002; Orléan 1989, 1990, 1992, 1998; Thévenot 2002], in the UK the Critical Realists [Fleetwood 1996; Lawson 1997, 1999; Lewis and Runde 2002], in the U.S. hybrid offshoots of Critical Realism [Davis 2002], in France, the U.S. and the UK Feminist Economics [Delphy 1984; Delphy and Leonard 1992; Feiner 1994, Nelson 1995; Barker and Feiner 2003]; in Switzerland, and elsewhere Experimental Economics [Fehr and Falk 2002; Fehr and Schmidt 1999], in the UK and US a new wave of Institutional Economics [Hodgson 1998, 2002; Mayhew 2002], as well as dispersed and assorted independents [Ackerman 2002; Akerlof 2002; Dow 1990; Fullbrook 2001, 2002, Hargreaves Heap 2002; Kaul 2002; Ormerod 2002; Rizvi 2002; Sofianou 1995; Stiglitz 2002a; Wynarczyk 2002] Will these and other developments lead to freeing economics from Descartes’ legacy, enabling it to reconnect with Adam Smith’s tradition?

End Note

1. There is of course also “intersubjectivity” in the modern epistemological and procedural sense of the testing of hypothesizes.

References

Ackerman, Frank (2002) “Flaws in the foundation: Consumer behavior and general equilibrium theory” in Edward Fullbrook (ed.) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 56-70.

Aglietta, Michel and André Orléan (2002) La monnaie entre violence et confiance, Paris: Odile Jacob.

Akerlof, George (2002) “Behavioral Macroeconomics and Macroeconomic Behavior”, The American Economic Review, June 2002, Vol. 92, No. 3, pp. 411-433.

Barker, Drucilla K and Susan Feiner (2003) Feminist Perspectives on Gender and the Economy, forthcoming, University of Michigan Press.

Bergson, Henri (1896, 1991) Matter and Memory, trans. N. M. Paul and W. S. Palmer, New York: Zone Books.

Du Bois, W. E. B. (1903, 1965) The Souls of Black Folk in Three Negro Classics, New York: Avon.

Brentano, Franz (1874, 1995) Psychology from an Empirical Standpoint, trans. Rancurello and Terrell, London: Routledge.

Davis, John B. (2002) “Collective intentionality and individual behavior” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 11-27.

Delphy, Christine (1984) Close to Home, London: Hutchinson.

Delphy, Christine and Diana Leonard (1992) Familiar Exploitation: A New Analysis of Marriage in Contemporary Western Society, Oxford: Polity Press.

Descartes, René ((1637) 1965) A Discourse on Method, trans. E. S. Haldane and G. R. T. Ross, New York: Washington Square Press.

Descartes, René (1641, 1970) “Mediations on First Philosophy” trans. E. Anscombe and P. T Geach in Descartes Philosophical Writings, London: The Open University.

Dow, Shelia C. (1990) "Beyond Dualism", Cambridge Journal of Economics, vol. 14, no. 2, pp. 143-158.

Dupuy, Jean-Pierre (1989) "Convention et Common knowledge." Revue économique, no. 2 mars, pp. 361-400.

Dupuy, Jean-Pierre (1991) La panique. Paris: Les empêcheurs de penser en round.

Dupuy, Jean-Pierre (2002) “Market, Imitation and Tradition: Hayek vs. Keynes” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 139-158.

Elias, Norbert (1978) What Is Sociology?, London: Hutchinson.

Fehr, E. and K. Schmidt (1999) “A Theory of Fairness, Competition and Cooperation”, Quarterly Journal of Economics, vol. 144, pp. 817-851.

Fehr, Ernst and Armin Falk (2002) “Reciprocal Fairness, Cooperation and Limits to Competition”, in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 28-55.

Feiner, Susan (editor) (1994) Race and Gender in the American Economy: Views Across the Spectrum, New York: Prentice Hall.

Fleetwood, Steve (1996) "Order without equilibrium: a critical realist interpretation of Hayek's notion of spontaneous order", Cambridge Journal of Economics, vol. 20, no. 6, November 1996, pp. 729-48.

Foley, Carlone A. (1893) “Fashion,” Economic Journal, vol. 3, September, pp. 458-474.

Fullbrook, Edward (1996) “Consumer Metaphysics: the Neoclassicists versus the Intersubjectivists”, Archives of Economic History, bol. vii, no. 1, pp. 53-74..

Fullbrook, Edward (1997) “Post-Modernising Homo Economicus”, Just Postmodernism, ed. Steven Earnshaw. Amsterdam and Atlanta: Rodopi, pp. 67-87.

Fullbrook, Edward (1998) “Caroline Foley and the Theory of Intersubjective Demand”, Journal of Economic Issues, Vol. XXXII, No. 3, pp. 709-731.

Fullbrook, Edward (2001) “Conceptual Displacement: From the Natural to the Social”, Review of Political Economy, Vol. LIX, No. 3, pp. 285-296.

Fullbrook, Edward (2002) “An intersubjective theory of value” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 273-299.

Hargreaves Heap, Shaun P. (2002) “’Everybody is talking about it’: Intersubjectivity and the television industry” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 123-138.

Hodgson, Geoffrey M. (1998) “The Approach of Institutional Economics”, Journal of Economic Literature, Vol. XXXVI, March, pp. 166-192.

Hodgson, Geoffrey M. (2002) “Reconstitutive downward causation: Social structure and the development of individual agency” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 159-180.

Hondrich, Ted (editor) 1995, The Oxford Companion to Philosophy, Oxford: Oxford University Press, 1995.

Hume, David (1739-40, 1978) A Treatise of Human Nature, Oxford: Oxford University Press.

Jevons, Willaim Stanley (1871, 1970) The Theory of Political Economy, Harmondsworth, England: Pelican.

Kaul, Nitasha (2002) “A critical ‘post to critical realism”, Cambridge Journal of Economics, Vol. 26, No. 6, pp. 709-726.

Keynes, John Maynard (1936) The General Theory of Employment, Interest and Money, London: MacMillan.

Lawson, Tony (1997) Economics and Reality, London: Routledge.

Lawson, Tony (1999) “What Has Realism Got to Do with It?”, Economics and Philosophy vol. 15 pp. 269-282.

Levy, Thierry (2002) “The Theory of Conventions and a New Theory of the Firm”, in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 254-272.

Lewis, David ((1969) Convention, Cambridge, Massachusetts: Harvard University Press.

Lewis, Paul and Jochen Runde (2002) Intersubjectivity in the socio-economic world: A Critical realist perspective” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 198-215.

Locke, John (1690, 1993) An Essay Concerning Human Understanding, London: Dent.

Mayhew, Anne (2002) “All consumption is conspicuous” in Edward Fullbrook (ed) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 43-55.

Mirowski, Philip (1989). More Heat Than Light, New York: Cambridge University Press.

Nelson, Julie A. (1995) Feminism, Objectivity and Economics, London: Routledge.

Orléan, André (1989) "Pour une approche cognitive des conventions économiques." Revue économique, no. 2 mars, pp. 241-72.

Orléan, André (1990) "Le role des influences interpersonnelles dans la formation des cours boursieers." Revue économique, no. 5, septembre.

Orléan, André (1992) "Contagion des opinions et founctionnement des marchés financiers." Revue économique no. 4, julliet, pp. 685-98.

Orléan, André (1998) “La monnaie autoréférentielle: réflexions sur les évolutions monétaires contemporaines” in Michel Aglietta and André Orléan (eds.) La Monnaie Souveraine, Paris: Odile Jacob, 1998.

Orléan, André (2003) “What Is a Collective Belief” in P. Bourgine and J.-P. Nadal (eds) Cognitive Economics, Berlin: Springer-Verlag, pp. 171-184.

Ormerod, Paul (2002) “Social networks and information” in Edward Fullbrook (ed.) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 216-230.

Petit, Jean-Luc (1999) “Constitution by Movement: Husserl in Light of Recent Neurobiological Findings” in Naturalizing Phenomenology: Issues in Contemporary Phenomenology and Cognitive Science, Jean-Luc Petit et al. editors. Stanford, California: Stanford University Press, pp. 220-244.

Poster, Mark (1975) Existential Marxism in Postwar France, Princeton, New Jersey: Princeton University Press.

Rawls, John (1971) A Theory of Justice. Cambridge, Mass: Harvard University Press.

Rizvi, S. Abu Turab (2002) “Adam Smith’s sympathy: Towards a normative economics” in Edward Fullbrook (ed.) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 241-253

Russell, Bertrand (1912, 1967) The Problems of Philosophy, Oxford: Oxford University Press.

Samuelson, Larry (2002) “Evolution and Game Theory”, Journal of Economic Perspectives, Vol. 16, No. 2, Spring, pp. 47-66.

Schelling, Thomas (1960, 1977) The Strategy of Conflict”, Oxford: Oxford University Press.

Shiller. R (1991) Market Volatility, Cambridge, Massachusetts: Massachusetts Institute of Technology Press.

Sofianou, Evanthia (1995) "Post-modernism and the notion of rationality in economics", Cambridge Journal of Economics, vol. 19, no. 2, pp. 373-90.

Smith, Adam (1776, 1979) The Wealth of Nations, Harmondsworth, England: Pelican.

Stiglitz, Joseph E. (2002a) “Information and the Change in the Paradigm in Economics”, The American Economic Review, Vol. 92, No. 3, pp. 460-501.

Stiglitz, Joseph E. (2002b) “There Is No Invisible Hand”, The Guardian, December 20, 2002.

Thévenot, Laurent (2002) “Conventions of co-ordination and the framing of uncertainty” in Edward Fullbrook (ed.) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 181-197.

Veblen, Thorstein (1894) “The Economic Theory of Woman’s Dress”, Popular Science Monthly, December, pp. 198-205. Reprinted in Essays in Our Changing Order, ed. L. Ardzroomi, New York: Viking Press, 1934.

Walras, Léon (1874-77, 1984) Elements of Pure Economics: or the Theory of Social Wealth, trans. William Jaffé, Philadelphia: Orion Editons.

Wynarczyk, Peter (2002) “The economics of criminal participation”: Radical subjectivist and intersubjectivist critiques” in Edward Fullbrook (ed.) Intersubjectivity in Economics: Agents and Structures, London and New York: Routledge, pp. 105-121.

homepage