University of Cologne, Germany Joint action and group agency have emerged as focuses of attention in recent social theory and philosophy but they have rarely been connected with one another. The argument of this article is that whereas joint action involves people acting together to achieve any sort of result, group agency requires them to act together for the achievement of one result in particular: the construction of a centre of attitude and agency that satisfies the usual constraints of consistency (...) and rationality in adequate measure. The main discovery in the recent theory of group agency is that this result is not easily achieved; no regular voting procedure will ensure, for example, that a group of individually consistent agents will display consistency in group judgments. Key Words: groups • group agents • collective agents • joint action • joint intention. (shrink)

Philosophers have proposed accounts of shared intentions that aim at capturing what makes a joint action intentionally joint. On these accounts, having a shared intention typically presupposes cognitively and conceptually demanding theory of mind skills. Yet, young children engage in what appears to be intentional, cooperative joint action long before they master these skills. In this paper, I attempt to characterize a modest or ‘lite’ notion of shared intention, inspired by Michael Bacharach’s approach to team–agency theory in terms of framing, (...) group identification and team reasoning. I argue that the account of shared intentions this approach yields is less cognitively and conceptually demanding than other accounts and is thus applicable to the intentional joint actions performed by young children. I also argue that it has limitations of its own and that considering what these limitations are may help us understand why we sometimes need to take other routes to shared intentions. (shrink)

Page 1. Economics and Philosophy, 26 291--320 Copyright C Cambridge University Press doi: 10.1017 / S0266267110000386 TWO KINDS OF WE-REASONING RAUL HAKLI, KAARLO MILLER AND RAIMO TUOMELA University of Helsinki.

Abstract Orthodox decision theory presupposes that agency is invested in individuals. An opposing literature allows team agency to be invested in teams whose members use distinctive modes of team reasoning. This paper offers a new conceptual framework, inspired by David Lewis's analysis of common reasons for belief, within which team reasoning can be represented. It shows how individuals can independently endorse a principle of team reasoning which prescribes acting as a team member conditional on assurance that others have endorsed the (...) same principle. It argues that there can be such assurance even when no individual has an obligation to act on team reasoning. *This paper originated in a lecture that I gave at a Colloquium on Collective Intentions at Erasmus University Rotterdam. I thank participants, and particularly Govert den Hartogh, for comments. The analysis presented in this paper is an offshoot of a larger project, which uses David Lewis's work as the starting point for a reconstruction of the foundations of game theory. That project is joint work with Robin Cubitt. The specific idea of using this approach to analyse team reasoning grew out of a discussion with Michael Bratman. My work was supported by the Leverhulme Trust. (shrink)

Individualists claim that collective obligations are reducible to the individual obligations of the collective’s members. Collectivists deny this. We set out to discover who is right by way of a deontic logic of collective action that models collective actions, abilities, obligations, and their interrelations. On the basis of our formal analysis, we argue that when assessing the obligations of an individual agent, we need to distinguish individual obligations from member obligations. If a collective has a collective obligation to bring about (...) a particular state of affairs, then it might be that no individual in the collective has an individual obligation to bring about that state of affairs. What follows from a collective obligation is that each member of the collective has a member obligation to help ensure that the collective fulfills its collective obligation. In conclusion, we argue that our formal analysis supports collectivism. (shrink)

A descriptive norm is a behavioral rule that individuals follow when their empirical expectations of others following the same rule are met. We aim to provide an account of the emergence of descriptive norms by first looking at a simple case, that of the standing ovation. We examine the structure of a standing ovation, and show it can be generalized to describe the emergence of a wide range of descriptive norms.

The chapter reviews recent theoretical and empirical developments concerning the theory of team reasoning in game theoretic interactions.

opinionated survey paper to be published in the Blackwell’s Philosophy Compass.

For as long as there have been markets, there have been complaints about market motives. For much of this history, the two sides have talked past one another. Optimists about markets have mostly addressed other optimists, and failed to take seriously the kinds of relational values that might be at stake and the range of possible alternatives to market-based production. Pessimists about markets have mostly addressed other pessimists, and failed to take seriously the full range of market-involving economic structures and (...) the different kinds of psychologies compatible with market interactions. Recently, there has been a break-through, on behalf of the optimists. According to the model of exchange as mutual assistance, an exchange can be perceived as a joint activity for mutual benefit - and needn't involve self-directed motives at all. This essay pushes back, on behalf of the market pessimists. The essay develops a contrast between exchange as mutual assistance and an ideal of production as caring solidarity, in which production is a joint activity of caring about one another. This alternative ideal draws on Marxist, socialist, feminist, and Christian traditions, and, in particular, on recent work on care, solidarity, and alienation. These two models – exchange as mutual assistance and production as caring solidarity – share key features, including an emphasis on reasoning from a ‘we-perspective’, on trusting one another, and on resisting a familiar self/other motivational dichotomy. Key differences are developed in detail. The essay concludes by discussing the implications for an economics of caring solidarity, with discussion of the limitations of various market socialist strategies. (shrink)

People walk, build, paint and otherwise act together with a purpose in myriad ways. What is the relation between the actions people perform in acting together with a purpose and the outcome, or outcomes, to which their actions are directed? We argue that fully characterising this relation will require appeal not only to intention, knowledge and other familiar philosophical paraphernalia but also to another kind of representation involved in preparing and executing actions, namely motor representation. If we are right, motor (...) representation plays a central role in the story of acting together. (shrink)

Cooperation admits of degrees. When factory workers stage a slowdown, they do not cease to cooperate with management in the production of goods altogether, but they are not fully cooperative either. Full cooperation implies that participants in a joint action are committed to rendering appropriate contributions as needed toward their joint end so as to bring it about, consistently with the type of action and the generally agreed upon constraints within which they work, as efficiently as they can, where their (...) contributions are sensitive to information (where available) about how others are contributing in the sense that they adjust as needed their contributions in light of information about how others are contributing to ensure effective pursuit of their joint end, where this includes rendering aid to other participants if needed, insofar as they are able. Full cooperation entails those cooperating are engaged in a joint intentional action. Some prominent studies of joint intentional action focus exclusively on cases of full cooperation (notably that of Michael Bratman (2014)). But not all joint intentional action is fully cooperative. One example is the work slowdown. Another example is provided by competitive games like chess and football, or sports like boxing and wrestling, where participants are clearly not intending to contribute to the pursuit of all of the goals of the others engaged in the activity, even when those goals are internal to the type of activity in question, but instead intend actively to frustrate some of them. In this paper, I provide a taxonomy of forms of non-cooperative behavior within the context of behavior that is still to some degree cooperative, and I argue that the minimal conditions of joint intentional action define minimal cooperative behavior, that is, that minimally joint intentional action is per se minimally cooperative behavior. I define in precise terms what that comes to, and how it is possible in cases in which it seems that one or more participants are in one or more ways acting so as to frustrate the contributions of other participants to their joint action. (shrink)

Standard game theory cannot explain the selection of payoff-dominant outcomes that are best for all players in common-interest games. Theories of team reasoning can explain why such mutualistic cooperation is rational. They propose that teams can be agents and that individuals in teams can adopt a distinctive mode of reasoning that enables them to do their part in achieving Pareto-dominant outcomes. We show that it can be rational to play payoff-dominant outcomes, given that an agent group identifies. We compare team (...) reasoning to other theories that have been proposed to explain how people can achieve payoff-dominant outcomes, especially with respect to rationality. Some authors have hoped that it would be possible to develop an argument that it is rational to group identify. We identify some large—probably insuperable—problems with this project and sketch some more promising approaches, whereby the normativity of group identification rests on morality. (shrink)

We-thinking theories allow groups to deliberate as agents. They have been introduced into the economic domain for both theoretical and empirical reasons. Among the few scholars who have proposed formal approaches to illustrate how we-thinking arises, Bacharach offers one of the most developed theories from the game theoretic point of view. He presents a number of intuitions, not always mutually consistent and not fully developed. In this article, I propose a way to complete Bacharach’s theory, generalizing the interdependence hypothesis and (...) building on his intuition about vacillation. It is a simple model of vacillation between the I and we-modes of reasoning, as a way in which we-thinking can come to mind in the face of a decision problem. The vacillation model makes we-reasoning more easily usable in game theory. (shrink)

Do responsibility voids exist? That is, are there situations in which the group is collectively morally responsible for some outcome although no member can be held individually morally responsible for it? To answer these questions, I draw a distinction between competitive and cooperative decision contexts based on the team-reasoning account of cooperation. Accordingly, I provide a reasoning-based analysis of cooperation, competition, moral responsibility, and, last, potential responsibility voids. I then argue that competitive decision contexts are free of responsibility voids. The (...) conditions for the existence of responsibility voids in cooperative decision contexts depend on the type of uncertainty the group faces, either external or coordination uncertainty. (shrink)

Abstract The specter of the ?group mind? or ?collective subject? plays a crucial and fateful role in the current debate on collective intentionality. Fear of the group mind is one important reason why philosophers of collective intentionality resort to individualism. It is argued here that this measure taken against the group mind is as unnecessary as it is detrimental to our understanding of what it means to share an intention. A non-individualistic concept of shared intentionality does not necessarily have to (...) get stuck with some collectivist super-agent. Rather, the specter of the group mind arises from a deep-seated ?Cartesian? preconception concerning intentionality, which we should try to overcome. *I am greatly indebted to Raimo Tuomela for his comments. Also, I wish to thank Michael Bratman, Fabienne Peter, Richard Raatzsch and Katrin Meyer. (shrink)

Over the last few decades, there have been intense debates concerning the effects of markets on the morality of individuals’ behaviour. On the one hand, several authors argue that markets’ ongoing expansion tends to undermine individuals’ intentions for mutual benefit and virtuous character traits and actions. On the other hand, leading economists and philosophers characterize markets as a domain of intentional cooperation for mutual benefit that promotes many of the character traits and actions that traditional virtue ethics accounts classify as (...) virtuous. In this paper, I join this debate and argue for three claims of general interest to philosophers, economists and policy makers. First, market transactions do not reliably promote individuals’ intentions for mutual benefit, and often select against such intentions. Second, the set of so-called market virtues lacks a substantial overlap with the set of character traits that traditional virtue ethics accounts classify as virtuous. And third, many seemingly virtuous actions observed in market contexts are merely actions in accordance with virtue rather than genuine actions from virtue. These three claims do not license opposition to markets, but challenge the main empirical and theoretical presuppositions of leading virtue ethics defences of markets. (shrink)

The game theoretic notion of best-response reasoning is sometimes criticized when its application produces multiple solutions of games, some of which seem less compelling than others. The recent development of the theory of team reasoning addresses this by suggesting that interacting players in games may sometimes reason as members of a team – a group of individuals who act together in the attainment of some common goal. A number of properties have been suggested for team-reasoning decision-makers’ goals to satisfy, but (...) a few formal representations have been discussed. In this paper we suggest a possible representation of these goals based on the notion of mutual advantage. We propose a method for measuring extents of individual and mutual advantage to the interacting decision-makers, and define team interests as the attainment of outcomes associated with maximum mutual advantage in the games they play. (shrink)

Decision theory explains weakness of will as the result of a conflict of incentives between different transient agents. In this framework, self-control can only be achieved by the I-now altering the incentives or choice-sets of future selves. There is no role for an extended agency over time. However, it is possible to extend game theory to allow multiple levels of agency. At the inter-personal level, theories of team reasoning allow teams to be agents, as well as individuals. I apply team (...) reasoning at the intra-personal level, taking the self as a team of transient agents over time. This allows agents to ask, not just “what should I-now do?’, but also ‘What should I, the person over time do?’, which may enable agents to achieve self-control. The resulting account is Aristotelian in flavour, as it involves reasoning schemata and perception, and it is compatible with some of the psychological findings about self-control. (shrink)

David Lewis famously proposed to model conventions as solutions to coordination games, where equilibrium selection is driven by precedence, or the history of play. A characteristic feature of Lewis Conventions is that they are intrinsically non-normative. Some philosophers have argued that for this reason they miss a crucial aspect of our folk notion of convention. It is doubtful however that Lewis was merely analysing a folk concept. I illustrate how his theory can (and must) be assessed using empirical data, and (...) argue that it does indeed miss an important aspect of real-world conventions. (shrink)

Starting from the sixties of the past century theory change has become a main concern of philosophy of science. Two of the best known formal accounts of theory change are the post-Popperian theories of verisimilitude (PPV for short) and the AGM theory of belief change (AGM for short). In this paper, we will investigate the conceptual relations between PPV and AGM and, in particular, we will ask whether the AGM rules for theory change are effective means for approaching the truth, (...) i.e., for achieving the cognitive aim of science pointed out by PPV. First, the key ideas of PPV and AGM and their application to a particular kind of propositional theories - the so called "conjunctive propositions" - will be illustrated. Afterwards, we will prove that, as far as conjunctive propositions are concerned, AGM belief change is an effective tool for approaching the truth. (shrink)

The concept of group identification has been widely discussed in the fields of social psychology and social ontology. The debate has been somewhat unbalanced, however. The structure, nature, and experiential status of groups have been assessed widely and from several perspectives. Instead, the concept of identification as received considerably less attention. This is why the ongoing debate threatens to be misled by various conceptual ambiguities. These ambiguities concern first and foremost the target, structure, and temporal nature of identification. The present (...) article offers a philosophical analysis of the concept and clarifies the conceptual ambiguities haunting the debate. (shrink)

If group members aim to fulfill a collective obligation, they must act in such a way that the composition of their individual actions amounts to a group action that fulfills the collective obligation. We study a strong sense of joint action in which the members of a group design and then publicly adopt a group plan that coordinates the individual actions of the group members. We characterize the conditions under which a group plan successfully coordinates the group members' individual actions, (...) and study how the public adoption of a plan changes the context in which individual agents make a decision about what to do. (shrink)

We present an inferentialist account of collective rationality and intentionality, according to which beliefs and other intentional states are understood in terms of the normative statuses attributed to, and undertaken by, the participants of a discursive practice—namely, their discursive or practical commitments and entitlements. Although these statuses are instituted by the performances and attitudes of the agents, they are not identified with any physical or psychological entity, process or relation. Therefore, we argue that inferentialism allows us to talk of collective (...) intentionality and agency without needing to posit the existence of any sort of collective psychology or mind. (shrink)

In this paper, I revisit the question of how and in what sense can individuals comprising a group be held responsible for morally reprehensible behaviour by that group. The question is tackled by posing a counterfactual: what would happen if selfish individuals became moral creatures? A game called the Samaritan’s Curse is developed, which sheds light on the dilemma of group moral responsibility, and raises new questions concerning ‘conferred morality’ and self-fulfilling morals, and also forces us to question some implicit (...) assumptions of game-theory. (shrink)

Cooperation is the foundation of human social life, but it sometimes requires individuals to choose against their individual self-interest. How then is cooperation sustained? How do we decide when instead to follow our own goals? I develop a model that builds on Bacharach (in: Gold, Sugden (eds) Beyond individual choice: teams and frames in game theory, 2006) ‘circumspect we-reasoning’ to address these questions. The model produces a threshold cost/benefit ratio to describe when we-reasoning players should choose cooperatively. After assumptions regarding (...) player types and beliefs, we predict how the extent of cooperation varies across games. Results from two experiments offer strong support to the models and predictions herein. (shrink)

According to some accounts, an individual participates in joint intentional cooperative action by virtue of conceiving of him- or herself and other participants as if they were parts of a single agent or body that performs the action. I argue that this notional singularization move fails if they act as if they were parts of a single agent. It can succeed, however, if the participants act as if to bring about the goal of a properly functioning single body in action (...) of which they would be parts. This latter version of the move manages to capture the cooperative character of joint intentional cooperative action. It does this without requiring of participants that they act on higher-order interlocking intentions. (shrink)

This paper examines two strands of literature regarding economic models of cooperation. First, payoff transformation theories assume that people may not be exclusively motivated by self-interest, but also care about equality and fairness. Second, team reasoning theorists assume that people might reason from the perspective of the team, rather than an individualistic perspective. Can these two theories be unified? In contrast to the consensus among team reasoning theorists, I argue that team reasoning can be viewed as a particular type of (...) payoff transformation. However, I also demonstrate that many payoff transformations yield actions that team reasoning rules out. (shrink)

The present paper proposes an integrative account of social forms of practical irrationality and corresponding disruptions of individual and group-level emotion regulation. I will especially focus on disruptions in emotion regulation by means of collaborative agential and doxastic akrasia. I begin by distinguishing mutual, communal and collaborative forms of akrasia. Such a taxonomy seems all the more needed as, rather surprisingly, in the face of huge philosophical interest in analysing the possibility, structure and mechanisms of individual practical irrationality, with very (...) little exception, there are no comparable accounts of social and collaborative cases. However, I believe that, if it is true that individual akrasia is, in the long run, harmful for those who entertain it, this is even more so in social contexts. I will illustrate this point by drawing on various small group settings, and explore a number of socio-psychological mechanisms underlying collaborative irrationality, in particular groupthink. Specifically, I suggest that in collaborative cases there is what I call a spiralling of practical irrationality at play. I will argue that this is typically correlated and indeed partly due to biases in individual members' affect control and eventually the group's with whom the members identify. (shrink)

This paper evaluates how Amartya Sen’s critique of revealed preference theory stands against the latter’s contemporary, ‘neo-Samuelsonian’ version. Neo- Samuelsonians have argued that Sen’s arguments against RPT are innocuous, in particular once it is acknowledged that RPT does not assume away the existence of motivations or other latent psychological or cognitive processes. Sen’s claims that preferences and choices need to be distinguished and that external factors need to be taken into account to analyze the act of choice then appear to (...) be irrelevant. However, while it is true that contemporary revealed preference theory partially evades Sen’s critique, I show that the latter is still relevant outside the restricted areas of consumer choice and market dynamics. In particular, Sen’s views regarding the importance of incomplete preferences and the multiplicity of levels of agency can hardly be integrated into the framework of CRPT. This is a significant limit, given the imperialistic claims of some of the proponents of the latter. (shrink)

This paper examines the idea of an extended unit of action, which is the idea that the reasons for or against an individual action can depend on the qualities of a larger pattern of action of which it is a part. One concept of joint action is that the unit of action can be extended in this sense. But the idea of an extended unit of action is surprisingly minimal in its commitments. The paper argues for this conclusion by examining (...) uses of the idea of an extended unit of action in four theoretical contexts. It also explains why the idea of an extended unit of action need not involve magical thinking, and discusses possible replies to an objection based on a worry about recklessness. (shrink)

The thesis of this essay is that social conventions of the kind Lewis modeled are generated and maintained by a form of practical reasoning which is essentially common. This thesis is defended indirectly by arguing for an interpretation of the role of salience in Lewis’s account of conventions. The remarkable ability of people to identify salient options and appreciate their practical significance in contexts of social interaction, it is argued, is best explained in terms of their exercise of what I (...) call “salience reasoning,” a form of common practical reasoning. The more widely accepted understanding of salience competence, the “natural salience” understanding, fails as an interpretation of the notion at work in Lewis and Schelling (on whom Lewis relied) and is inadequate as an explanation of salience competence. (shrink)

Mainstream game theory explains cooperation as the outcome of the interaction of agents who permanently pursue their individual goals. Amartya Sen argues instead that cooperation can only be understood by positing a type of rule-following behaviour that can be out of phase with the pursuit of individual goals, due to the existence of a collective identity. However, Sen does not clarify the ontological preconditions for the type of social behaviour he describes. I will argue that Sen's account of collective identity (...) can be best interpreted in the light of John Searle's notion of collective intentionality, while Sen's explanation of rule-following behavior and agency is best understood using the critical realist transformational model of social activity. (shrink)

This article aims to contribute to a critical ontology of social objects. Recent works on collective intentionality and norm-following neglect the question how free agents can be brought to collectively intend to x , although x is not in their own interest. By arguing for a natural disposition to empathic understanding and drawing on recent research in the neurosciences, this article outlines an ontological framework that extends collective intentionality to questions of oppression and status asymmetries. In a contribution to this (...) journal, Wisnewski (2005) unfortunately mischaracterizes the problem of meaning in social criticism. Implementing status problems in studies of collective intentions and construing social facts as both subjective and objective in character helps explain why agents can have persistent "misunderstandings" of social objects. (shrink)

Mind reading (i.e. the ability to infer the mental state of another agent) is taken to be the main cognitive ability required to share an intention and to collaborate. In this paper, I argue that another cognitive ability is also necessary to collaborate: representing others’ and ones’ own goals from a third-person perspective (other-centred or allocentric representation of goals). I argue that allocentric mind reading enables the cognitive ability of goal adoption, i.e. having the goal that another agent’s achieve p (...) because and as long as another agent has that goal that p. Having clarified the relevance of mutual goal adoption for acting jointly, I argue that when an intention is shared between several agents, each individual has an intention in favour of the joint action and one in favour of a joint mode of reasoning. This mode of reasoning is allocentric reasoning. Finally, I elaborate on the consequences of this view for the scientific study of human collaboration. (shrink)

How do rational agents coordinate in a single-stage, noncooperative game? Common knowledge of the payoff matrix and of each player's utility maximization among his strategies does not suffice. This paper argues that utility maximization among intentions and then acts generates coordination yielding a payoff-dominant Nash equilibrium. ‡I thank the audience at my paper's presentation at the 2006 PSA meeting for many insightful points. †To contact the author, please write to: Philosophy Department, University of Missouri, Columbia, MO 65211; e-mail: [email protected].

Economic theories of team reasoning build on the assumption that agents can sometimes behave according to beliefs or preferences attributed to a group or a team. In this paper, I propose a different framework to introduce collective intentionality into game theory. I build on John Searle’s account, which makes collective intentionality constitutive of institutional facts. I show that as soon as one accepts that institutions are required to solve indetermination problems in a game, it is necessary to assume a form (...) of collective intentionality that comes from what I call a common understanding of the situation among the players. This common understanding embodies the epistemic requirements for an institution to be a correlated equilibrium in a game. As a consequence, I question recent claims made by some economists according to which game-theoretic accounts of institutions do not need to assume collective intentionality. (shrink)

This paper pursues a naturalist endeavor in social ontology by arguing that the Beliefs-Rules-Equilibrium account of institutions can help to advance the debate over the nature of social kinds. This account of institutions emerges from a growing number of works in economics that use game theory to study the role and the functioning of institutions in human societies. I intend to show how recent developments in the economic analysis of rules and institutions can help solve issues that are generally considered (...) constitutive of any ontological inquiry. I argue that the Beliefs-Rules-Equilibrium account of institutions can contribute to advancing the debate on an issue of particular importance, regarding the specific form of dependence characterizing the relation between institutions and individuals’ attitudes about them. I tackle this issue by taking Francesco Guala's claims about the nature of institutions made in his book “Understanding Institutions” as a point of departure. In particular, I reject Guala’s functionalism about institutions. On the basis of the Beliefs-Rules-Equilibrium account, I claim that it is futile to search for constitutive features of general institutions (money, property rights, family…) and that the best we can have is a knowledge of what are the rules within a specific institution, which the agents consider to be essential in their institutional practice. (shrink)

This paper explores the implications of a Civil Economy approach to consumer ethics, by addressing the idea that Antonio Genovesi’s (1713–1769) notion of _mutual assistance_ can be understood in terms of _collective intentionality_ or _team reasoning_. I try to give reasons for this idea by a careful examination of Genovesi’s conception of social life and human agency and by reading it through the lens of team reasoning. I argue that this understanding of mutual assistance may imply broad constraints over agents’ (...) choices whenever they conflict with the good of society. Then I explore the implications of a mutual assistance approach to market ethics in a global society, where conflicting views of good and different group affiliations are possible. (shrink)

Understanding Institutions offers a theory that is able to unify the two dominant approaches in the scientific and philosophical literature on institutions. Moreover, using the ‘rules-in-equilibrium’ theory, it tackles several ancient puzzles in the philosophy of social science.

The unintendedness of the phenomenon that is to be explained is a constraint visible in the various applications and clarifications of invisible-hand explanations. The article casts doubt on such a requirement and proposes a revised account. To have a role in an invisible-hand process, it is argued, agents may very well act with a view to contributing to the occurrence of the social outcome that is to be explained, provided they see what they do as an aggregation of their individual (...) actions rather than as something they jointly perform. (shrink)

This paper proposes a new interpretation of non-cooperative games that shows why the unilateralism of best-reply reasoning fails to capture the mutuality of strategic interdependence. Drawing on an intersubjective approach to theorizing individual agency in shared context, including a non-individualistic model of common belief without infinite regress, the paper develops a general model of a 2 × 2 simultaneous one-shot non-cooperative game and applies it to games including Hi-Lo, Stag Hunt, Prisoners’ Dilemma, Chicken, BoS and Matching Pennies. Results include High (...) as the rational choice in Hi-Lo, and Cooperate as a possible rational choice in the Prisoners’ Dilemma. (shrink)

The paper aims to clarify and scrutinize Searle"s somewhat puzzling statement that collective intentionality is a biologically primitive phenomenon. It is argued that the statement is not only meant to bring out that "collective intentionality" is not further analyzable in terms of individual intentionality. It also is meant to convey that we have a biologically evolved innate capacity for collective intentionality.The paper points out that Searle"s dedication to a strong notion of collective intentionality considerably delimits the scope of his endeavor. (...) Furthermore, evolutionary theory does not vindicate that an innate capacity for collective intentionality is a necessary precondition for cooperative behavior. 1. (shrink)

The paper begins by providing a game-theoretic reconstruction of Gilbert’s (1989) philosophical critique of Lewis (1969) on the role of salience in selecting conventions. Gilbert’s insight is reformulated thus: Nash equilibrium is insufficiently powerful as a solution concept to rationalize conventions for unboundedly rational agents if conventions are solutions to the kinds of games Lewis supposes. Both refinements to NE and appeals to bounded rationality can plug this gap, but lack generality. As Binmore (this issue) argues, evolutive game theory readily (...) explains the origin of conventional behavior, but that is not Lewis’s project. Gilbert’s critique is generalized by reference to Bacharach’s (2006) work on team reasoning in games. The paper then argues that although Lewis’s account of the rationalization of conventions is shown by the reconstruction of Gilbert’s critique to be incomplete, Gilbert is wrong to conclude that classical (‘eductive’) game theory lacks the resources to explain conformity to conventions among people. A game-theoretic account of the dynamics of socialization, based on Ross’s (2005, 2006) idea of ‘game determination’, rationalizes choices of conventional strategies in overlapping generations contexts, provided agents are products of evolutionary selection and know that other players are also such products. (shrink)

On many occasions, individuals are able to coordinate their actions. The first empirical evidence to this effect has been described by Schelling (1960) in an informal experiment. His results were corroborated many years later by Mehta et al. (1994a,b) and Bacharach and Bernasconi (1997). From the point of view of mainstream game theory, the success of individuals in coordinating their actions is something of a mystery. If there are two or more strict Nash equilibria, mainstream game theory has no means (...) of explaining why people tend to choose their part of one and the same equilibrium. Textbooks (see, e.g., Rasmusen, 1989 and Kreps, 1990) refer to the fact that players may use focal points (see Schelling (1960)) or social conventions (see Lewis (1969)). Both notions cannot easily be incorporated into mainstream game theory, however. The notion of social conventions has recently been extensively studied in the context of evolutionary game theory where a population of agents interacts with each other. The central focus of this paper, however, is on situations where a few players play a game only once and I study how they may coordinate their actions. (shrink)

A particular problem of traditional Rational Choice Theory is that it cannot explain equilibrium selection in simple coordination games. In this paper we analyze and discuss the solution concept for common coordination problems as incorporated in the theory of Team Reasoning (TR). Special consideration is given to TR’s concept of opportunistic choice and to the resulting restrictions in using private information. We report results from a laboratory experiment in which teams were given a chance to coordinate on a particular pattern (...) of behavior in a sequence of HiLo games. A modification of the stage game offered opportunities to improve on the team goal through changing this accustomed pattern of behavior. Our observations throw considerable doubt on the idea of opportunistic team reasoning as a guide to coordination. Contrary to what TR would predict, individuals tend to stick to accustomed behavioral patterns. Moreover, we find that individual decisions are at least partly determined by private information not accessible to all members of a team. Alternative theories of choice, in particular cognitive hierarchy theory may be more suitable to explain the observed pattern of behavior. (shrink)

Team reasoning gives a simple, coherent, and rational explanation for human cooperative behavior. This paper investigates the robustness of team reasoning as an explanation for cooperative behavior, by assessing its long-run viability. We consider an evolutionary game theoretic model in which the population consists of team reasoners and ‘conventional’ individual reasoners. We find that changes in the ludic environment can affect evolutionary outcomes, and that in many circumstances, team reasoning may thrive, even under conditions that, at first glance, may seem (...) unfavorable. We also pursue several extensions that augment the basic account, and conclude that team reasoning is an evolutionarily viable mechanism with the potential to explain behavior in a range of human interactions. (shrink)