Un grand nombre de problèmes dont traite aujourd'hui la théorie de la décision reposent sur des problématiques qui appartiennent à des approches philosophiques, méthodologiques et théoriques fort différentes et dont l'auteur deChoix rationnel et vie publiquedéplore à juste titre l'absence d'unité intrinsèque. En effet, les racines de la théorie contemporaine du choix rationnel ont des ramifications dans trois traditions philosophiques qui ont été maintenues sans entretenir de contacts: théories philosophiques de l'action d'Aristote à Hume, à Kant et à la philosophie (...) analytique de l'action de Davidson; la théorie du conflit de Hobbes à David Gauthier; la théorie de la justice (d'inspiration utilitariste qui a profondément marqué la pensée économique du XXesiècle). Ces branches ont entretenu des interactions sporadiques, mais ces relations n'ont jamais été exploitées systématiquement. Le travail que présente l'auteur est une première tentative dans cette direction, du moins en langue française. (shrink)

Does rational bargaining yield a social contract that is efficient and so inclusive? A core allocation, that is, an allocation that gives each coalition at least as much as it can get on its own, is efficient. However, some coalitional games lack a core allocation, so rationality does not require one in those games. Does rationality therefore permit exclusion from the social contract? I replace realization of a core allocation with another type of equilibrium achievable in every coalitional game. Fully (...) rational agents coordinate the pursuit of incentives so that equilibria of this type are efficient. They adopt a social contract that is efficient and inclusive. (shrink)

Group decisions raise a number of substantial philosophical and methodological issues. We focus on the goal of the group decision exercise itself. We ask: What should be counted as a good group decision-making result? The right decision might not be accessible to, or please, any of the group members. Conversely, a popular decision can fail to be the correct decision. In this paper we discuss what it means for a decision to be "right" and what components are required in a (...) decision process to produce happy decision-makers. Importantly, we discuss how "right" decisions can produce happy decision-makers, or rather, the conditions under which happy decision-makers and right decisions coincide. In a large range of contexts, we argue for the adoption of formal consensus models to assist in the group decision-making process. In particular, we advocate the formal consensus convergence model of Lehrer and Wagner (1981), because a strong case can be made as to why the underlying algorithm produces a result that should make each of the experts in a group happy. Arguably, this model facilitates true consensus, where the group choice is effectively each person's individual choice. We analyse Lehrer and Wagner's algorithm for reaching consensus on group probabilities/utilities in the context of complex decision-making for conservation biology. While many conservation decisions are driven by a search for objective utility/probability distributions (regarding extinction risks of species and the like), other components of conservation management primarily concern the interests of stakeholders. We conclude with cautionary notes on mandating consensus in decision scenarios for which no fact of the matter exists. For such decision settings alternative types of social choice methods are more appropriate. (shrink)

This paper contributes to the (re-)conceptualisation of responsible innovation by proposing an evolutionary economic approach that focuses on the role of consumers in the innovation process. After a discussion of the philosophical foundations and ethical implications of this approach, which bears an explanatory potential that has not been adequately considered in previous discussions of responsible innovation, we present a first step towards capturing the important but often neglected role of consumers in innovation processes (including responsible innovation): We propose an agent-based (...) model that incorporates a multidimensional space of characteristics in which new products or services are represented by more than the mere aspect of price and quality. Instead, innovations are denoted by a large set of characteristics, including also negative or harmful ones. The model is used to illustrate that consumers’ heterogeneity and bounded rationality – even if considered in a simple manner – indeed play a crucial role in the creation and diffusion of responsible innovation which can and should be used for further work in this field and for possible extensions of the model. (shrink)

Precautionary Principles are often said to be appropriate for decision-making in contexts of uncertainty such as climate policy. Contexts of uncertainty are contrasted to contexts of risk depending on whether we have probabilities or not. Against this view, I argue that the risk-uncertainty distinction is practically irrelevant. I start by noting that the history of the distinction between risk and uncertainty is more varied than is sometimes assumed. In order to examine the distinction, I unpack the idea of having probabilities, (...) in particular by distinguishing three interpretations of probability: objective, epistemic, and subjective probability. I then claim that if we are concerned with whether we have probabilities at all—regardless of how low their epistemic credentials are—then we almost always have probabilities for policy-making. The reason is that subjective and epistemic probability are the relevant interpretations of probability and we almost always have subjective and epistemic probabilities. In contrast, if we are only concerned with probabilities that have sufficiently high epistemic credentials, then we obviously do not always have probabilities. Climate policy, for example, would then be a case of decision-making under uncertainty. But, so I argue, we should not dismiss probabilities with low epistemic credentials. Rather, when they are the best available probabilities our decision principles should make use of them. And, since they are almost always available, the risk-uncertainty distinction remains irrelevant. (shrink)

Following a long-standing philosophical tradition, impartiality is a distinctive and determining feature of moral judgments, especially in matters of distributive justice. This broad ethical tradition was revived in welfare economics by Vickrey, and above all, Harsanyi, under the form of the so-called Impartial Observer Theorem. The paper offers an analytical reconstruction of this argument and a step-wise philosophical critique of its premisses. It eventually provides a new formal version of the theorem based on subjective probability.

This article attempts to assess Jon Elster's contribution to rational choice in Ulysses and the Sirens and Sour Grapes. After reviewing Elster's analysis of functional versus intentional explanations, the essay moves on to the crucial distinction between the thin and broad theories of rationality. The former elabo rates on the traditional economist's preference / feasible set apparatus; the latter is the more demanding theory which inquires into the rationality of beliefs and preferences. Elster's approach to the broad theory normally consists (...) in using the thin theory as a reference point and in making purposefully limited departures from it. The essay illustrates the method while commenting on Elster's discus sion of autonomous preferences in Sour Grapes. It goes on to stress some impor tant analogies between Elster's use of the thin and broad theories, on one hand, and Weber's ideal-typical method, on the other. The final assessment is phrased in terms of these analogies; it is suggested that Elster is at his best when the ideal-typical method and his own separate from each other, that is, when he comes to grips with the broad theory in its own terms. (shrink)

This French paper is a preliminary version of P. Mongin, "Does Optimization Imply Rationality?", Synthese, 124, 2000, p. 73-111, to which readers are referred to.

The relations between rationality and optimization have been widely discussed in the wake of Herbert Simon's work, with the common conclusion that the rationality concept does not imply the optimization principle. The paper is partly concerned with adding evidence for this view, but its main, more challenging objective is to question the converse implication from optimization to rationality, which is accepted even by bounded rationality theorists. We discuss three topics in succession: (1) rationally defensible cyclical choices, (2) the revealed preference (...) theory of optimization, and (3) the infinite regress of optimization. We conclude that (1) and (2) provide evidence only for the weak thesis that rationality does not imply optimization. But (3) is seen to deliver a significant argument for the strong thesis that optimization does not imply rationality. (shrink)

La théorie du choix social qui s'est développée durant les dernières décennies, notamment dans la ligne des travaux d'Arrow et de Sen , ne s'est pas seulement soldée par une série de résultats négatifs exprimés dans les théorèmes d'impossibilité d'Arrow, de Sen et d'autres; ses notions centrales ont aussi été utilisées de manière fort variée au point que cette théorie souffre aujourd'hui d'un déficit important qui se traduit par de multiples indéterminations conceptuelles.

Richard Levins has advocated the scientific merits of qualitative modeling throughout his career. He believed an excessive and uncritical focus on emulating the models used by physicists and maximizing quantitative precision was hindering biological theorizing in particular. Greater emphasis on qualitative properties of modeled systems would help counteract this tendency, and Levins subsequently developed one method of qualitative modeling, loop analysis, to study a wide variety of biological phenomena. Qualitative modeling has been criticized for being conceptually and methodologically problematic. As (...) a clear example of a qualitative modeling method, loop analysis shows this criticism is indefensible. The method has, however, some serious limitations. This paper describes loop analysis, its limitations, and attempts to clarify the differences between quantitative and qualitative modeling, in content and objective. Loop analysis is but one of numerous types of qualitative analysis, so its limitations do not detract from the currently underappreciated and underdeveloped role qualitative modeling could have within science. (shrink)

The rational choice paradigm has proved to be a fruitful means of analysis and explanation in various disciplines concerned with questions of practical rationality, but in various attempts to extend its fields of application the deficiencies of the original account of rational choice have become evident. This paper tries to give a systematic overview of ways in which the rational choice paradigm can be extended and modified.

Supporters of political realism and republicanism as well as students of political feasibility and non-ideal theory progressively focus on the dimension of power in the political relation. Yet we lack the theoretical framework to represent these features of power. In this essay, I take a first step towards designing the necessary conceptual tools for such a framework by analyzing the relations between the concepts of power and normativity that define the political relation. Adopting a ‘methodological cynicism’, I analyse the reasons (...) that motivate cynics who are only interested in power to obey a norm against force or violence and to seek legitimacy. This allows us to characterize external or mediate relations between power and normativity (such as the relation underlying political theory’s ambition of offering normative guidance for power) and identify internal and immediate relations between power and normativity. (shrink)

Many authors in ethics, economics, and political science endorse the Lottery Requirement, that is, the following thesis: where different parties have equal moral claims to one indivisible good, it is morally obligatory to let a fair lottery decide which party is to receive the good. This article defends skepticism about the Lottery Requirement. It distinguishes three broad strategies of defending such a requirement: the surrogate satisfaction account, the procedural account, and the ideal consent account, and argues that none of these (...) strategies succeed. The article then discusses and discharges some remaining grounds for resistance to these skeptical conclusions, as well as the possibility of defending a weaker version of a normative lottery principle. The conclusion is that we have no reason to believe that where equal claims conflict, we are morally required to hold a lottery, as opposed to simply picking one of the parties on more subjective grounds or out of pure whim. In addition to the practical consequences of this skeptical view, the article sketches some theoretical implications for debates about saving the greater number and about axiomatic utilitarianism. (shrink)

The paper first summarizes the author's decision-theoretical model of moral behavior, in order to compare the moral implications of the act-utilitarian and of the rule-utilitarian versions of utilitarian theory. This model is then applied to three voting examples. It is argued that the moral behavior of act-utilitarian individuals will have the nature of a noncooperative game, played in the extensive mode, and involving action-by-action maximization of social utility by each player. In contrast, the moral behavior of rule-utilitarian individuals will have (...) the nature of a cooperative game, played in the normal mode, and involving a firm commitment by each player to a specific moral strategy (viz. to the strategy selected by the rule-utilitarian choice criterion) — even if some individual actions prescribed by this strategy, when considered in isolation, should fail to maximize social utility. The most important advantage that rule utilitarianism as an ethical theory has over act utilitarianism lies in its ability to give full recognition to the moral and social importance of individual rights and personal obligations. It is easy to verify that action-by-action maximization of social utility, as required by act utilitarianism, would destroy these rights and obligations. In contrast, rule utilitarianism can fully recognize the moral validity of these rights and obligations precisely because of its commitment to an overall moral strategy, independent of action-by-action social-utility maximization. The paper ends with a discussion of the voter's paradox problem. The conventional theory of rational behavior cannot avoid the paradoxical conclusion that, in any large electorate, voting is always an irrational activity because one's own individual vote is extremely unlikely to make any difference to the outcome of any election. But it can be shown that, by using the principles of rule-utilitarian theory, this paradox can easily be resolved and that, in actual fact, voting, even in large electorates, may be perfectly rational action. More generally, the example of rule utilitarianism shows what an important role the concept of a rational commitment can play in the analysis of rational behavior. (shrink)

It is argued that we need a richer version of Bayesian decision theory, admitting both subjective and objective probabilities and providing rational criteria for choice of our prior probabilities. We also need a theory of tentative acceptance of empirical hypotheses. There is a discussion of subjective and of objective probabilities and of the relationship between them, as well as a discussion of the criteria used in choosing our prior probabilities, such as the principles of indifference and of maximum entropy, and (...) the simplicity ranking of alternative hypotheses. (shrink)

Using the mathematical frameworks of economic preference ranking, subjective probability, and rational learning through empirical evidence, the epistemological implications of teleological ethical intuitionism are pointed out to the extent to which the latter is based on cognitivist and objectivist concepts of value. The notions of objective value and objective norm are critically analysed with reference to epistemological criteria of intersubjectively shared valuative experience. It is concluded that one cannot meaningfully postulate general material theories of morality that could be tested, confirmed (...) or refuted by intersubjective empirical evidence of preferences and values, however loosely the empirical evidence of values may be interpreted. This situation is explained with reference to the ways in which preceived values become systematically influenced by the concomitants of individual valuative experience, but which have nothing to do with contingent subjective interests. (shrink)

This paper uses John Rawls' theory of justice to defend the patent system against charges that it has an unfair effect on access to medications, from the perspective of national and international justice. The paper argues that the patent system is fair in a national context because it respects intellectual property rights and it benefits the least advantaged members of society by providing incentives for inventors, investors, and entrepreneurs. The paper also argues that the patent system is fair in an (...) international context, provided that developed nations take steps to help disease-stricken countries secure internal justice. Fairness in a national or international context also requires that the patent system should include emergency exceptions to deal with short-term inequities. (shrink)

We study questionnaire responses to situations in which sacrificing one life may save many other lives. We demonstrate gender differences in moral judgments: males are more supportive of the sacrifice than females. We investigate a source of the endorsement of the sacrifice: antisocial preferences. First, we measure individual proneness to spiteful behavior, using an experimental game with monetary stakes. We demonstrate that spitefulness can be sizable—a fifth of our participants behave spitefully—but it is not associated with gender. Second, we find (...) that gender is consistently associated with responses even when we account for individual differences in the propensity to spitefulness. (shrink)

In this paper we distinguish two competing conceptions of dignity, one recognizably Hobbesian and one recognizably Kantian. We provide a formal model of how decision-makers committed to these conceptions of dignity might reason when engaged in an economic transaction that is not inherently insulting, but in which it is possible for the dignity of the agent to be called into question. This is a modified version of the ultimatum game. We then use this model to illustrate ways in which the (...) Kantian evaluative standpoint enjoys a kind of internal stability that the Hobbesian framework lacks. Our interpersonal argument shows that, under certain conditions, Hobbesians prefer to cultivate Kantian commitments in others and promote the presence of Kantians in the population. Our intrapersonal argument shows that agents who are conflicted between Kantian and Hobbesian commitments have powerful reasons not to resolve this commitment in favour of Hobbesian values. Our emulation argument illustrates that in repeated versions of the ultimatum game, the Hobbesian chooses to behave like a Kantian, including publicly repudiating her Hobbesian commitments. Here again, however, the Hobbesian is able to achieve a desired benefit only on the condition that there are genuine Kantians in the population. Finally, our social planning argument explores the reasons why a community of Hobbesians would opt to enshrine a Kantian conception of dignity into law. The paper concludes with some remarks about the policy implications of this work. The value or worth of a man is, as for all other things, his price, that is to say, so much as would be given for the use of his power; and therefore is not absolute, but a thing dependent on the need and judgement of another... The public worth of a man, which is the value set on him by the Common-wealth, is that which men commonly call DIGNITY. Hobbes, _Leviathan X_, 16. (shrink)

The paper analyses economic evaluations by distinguishing evaluative statements from actual value judgments. From this basis, it compares four solutions to the value neutrality problem in economics. After rebutting the strong theses about neutrality (normative economics is illegitimate) and non-neutrality (the social sciences are value-impregnated), the paper settles the case between the weak neutrality thesis (common in welfare economics) and a novel, weak non-neutrality thesis that extends the realm of normative economics more widely than the other weak thesis does.

The main goal of this thesis is to provide a clear basis for the analysis of alternative currencies, such as Bitcoin, LETS, Local currencies, the WIR or Carbon currencies. It attempts to determine whether alternative currencies might constitute just and workable alternatives, either in the form of small-scale experiments or in the form of more radical reforms. The first chapter proposes a new way to classify currencies. The second examines the case in favour of monetary plurality. The third analyses the (...) claims in favour of restricting the use of money locally, within a community, or to certain goods. The fourth studies the link between money and the market. Finally, a post-scriptum focuses on Bitcoin and cryptocurrencies. This thesis highlights that these currencies are drivers of several potential conflicts. Their widespread use might conflict with the adequate management of monetary policy, with social justice, and with liberal values. These conflicts are potential, for they would come into existence only if alternative currencies increased in scope. However, there is no reason to disregard potential conflicts when the case in their favour relies mostly on their potential benefits. (shrink)

forthcoming in M.C. Galavotti, R. Scazzieri and P. Suppes (eds.), Reasoning, Rationality and Probability, Stanford: CSLI Publications 2006.

One of the hallmark themes of Karl Popper’s approach to the social sciences was the insistence that when social scientists are members of the society they study, then they are liable to affect that society. In particular, they are liable to affect it in such a way that the claims they make lose their validity. “The interaction between the scientist’s pronouncements and social life almost invariably creates situations in which we have not only to consider the truth of such pronouncements, (...) but also their actual influence on future developments. The social scientist may be striving to find the truth; but, at the same time, he must always be exerting a definite influence upon society. The very fact that his pronouncements do exert an influence destroys their objectivity.” (Popper 1963. (shrink)

Equal and proportional representation are two poles of a continuum of models of representation for the assembly of a federation of states. The choice of a model has repercussions on the welfare distribution in the federation. We determine, first by means of Monte Carlo simulations, what welfare distributions result after assemblies that were constituted on the basis of different models of representation have considered a large number of motions. We assess what model of representation is favored by a Rawlsian maximin (...) measure and by the utilitarian measure and present matching analytical results for the utilitarian measure for a slightly idealized case. Our results show that degressive proportionality can be justified as a compromise between maximin and utilitarian considerations. There is little surprise in this result. What is more surprising, however, is that, within certain contexts of evaluation, degressive proportionality can also be justified on strictly utilitarian grounds. (shrink)