Game theory is the systematic study of interdependent rational choice. It should be distinguished from decision theory, the systematic study of individual (practical and epistemic) choice in parametric contexts (i.e., where the agent is choosing or deliberating independently of other agents). Decision theory has several applications to ethics (see Dreier 2004; Mele and Rawlings 2004). Game theory may be used to explain, to predict, and to evaluate human behavior in contexts where the outcome of action depends on what several agents (...) choose to do and where their choices depend on what others choose to do. (See the entry on game theory) Game theory consequently is relevant to ethics, and it is used in moral and political philosophy in a variety of ways. We shall concentrate on the influence and use of game theory in ethics and those parts of political theory involving norms or principles of justice, ignoring questions about political and legal institutions on the one hand and questions about issues dealing with moral virtues on the other. (shrink)

I review the classic skeptical challenges of Foole in Leviathan and the Lydian Shepherd in Republic against the prudential rationality of justice. Attempts to meet these challenges contribute to the reconciliation project (Kavka in Hobbesian moral and political theory , 1986 ) that tries to establish that morality is compatible with rational prudence. I present a new Invisible Foole challenge against the prudential rationality of justice. Like the Lydian Shepherd, the Invisible Foole can violate justice offensively (Kavka, Hobbesian moral and (...) political theory , 1986 ; Law and Philosophy , 14:5–34, 1995 ) without harming his reputation for justice. And like the Foole, the Invisible Foole dismisses the possibility that being just preserves goods intrinsic to justice, and will be just only if he fears that others will punish his injustice by withholding the external goods like labor and material goods that he would otherwise receive for their performance in covenants. I argue that given a plausible folk-theorem interpretation , Hobbes’ response to the Foole’s challenge is inconclusive, and depends crucially upon common knowledge assumptions that may or may not obtain in actual societies. I present two analogous folk-theorem arguments in response to the Invisible Foole’s challenge, one using the idea that the Invisible Foole’s power of concealment might be transitory, and the other using the idea that members of society might stop performing in covenants with anyone, thus punishing the Invisible Foole indirectly, if the Invisible Foole commits sufficiently many injustices. (shrink)

Learning to take turns in repeated game situations is a robust phenomenon in both laboratory experiments and in everyday life. Nevertheless, it has received little attention in recent studies of learning dynamics in games. We investigate the simplest and most obvious extension of fictitious play to a learning rule that can recognize patterns, and show how players using this rule can spontaneously learn to take turns.

In recent years, a number of authors have used gametheoretic reasoning to explain why purely self-interested agentswould ever conform their economic activities with the requirements of justice, when by doing so they forego opportunities to reapunilateral net gains by exploiting others. In this paper, I argue that Hume's justification of honest economic exchanges between self-interested agents in the Treatise foreshadows this contemporary literature. Hume analyzes the problem of explaining justice in self-interested economic exchange as a problem of agents coordinating on (...) a pattern of reciprocal cooperation, as opposed to some other behavioral pattern such as reciprocal exploitation, in exchanges repeated over time. Hume's arguments anticipate informally thecontemporary interpretation of just economic practices as forming part of an equilibrium of a repeated game. I close the paper by arguing that Hume does not provide a satisfactory explanation of how the mutual expectations that support justice in economic exchange arise in a community of self-interested agents. The problem Hume leaves unsolved is one of equilibrium selection, that is: Why do agents follow an equilibrium corresponding to just economic exchanges rather than some other equilibrium corresponding to unjust exchanges? I also argue that contemporary game theory still lacks a satisfactory theory of equilibrium selection, but that such a theory would lead us closer to a satisfactory Humean reconciliation of justice and self-interest in economic exchange. (shrink)

Abstract:In recent years, many business ethicists have raised problems with the “ethics pays” credo. Despite these problems, many continue to hold it. I argue that support for the credo leads business ethicists away from a potentially fruitful approach found in Hume’s moral philosophy. I begin by demonstrating that attempts to support the credo fail because proponents are trying to provide an answer to the “Why be moral?” question that is based on rational self-interest. Then, I show that Hume’s sentiments-based moral (...) theory provides an alternative to the credo that points toward a more fruitful approach to business ethics. Along the way, I examine a recent social contract alternative to the credo that, despite many appealing features, is less effective than is the Humean alternative. Finally, I develop a Humean approach to business ethics and demonstrate why it is a desirable alternative that business ethicists should explore. (shrink)

This article surveys the main philosophical and formal ideas revolving around language as being conventional from the perspective of game theory. For very basic situations, this leads to a coherent view of conventions that offers interesting insights. Although there exist many open problems, this article will argue by outlining partial solution attempts that there is no principled reason for not applying methods from game theory to them.

It is a truism that a market economy cannot function without trust. We must be able to rely on other people to respect our property rights, and on our trading partners to keep their promises. The theory of economics is incomplete unless it can explain why economic agents often trust one another, and why that trust is often repaid. There is a long history of work in economics and philosophy which tries to explain the kinds of reasoning that people use (...) when they engage in practices of trust: this work develops theoriesoftrust. A related tradition in economics, sociology and political science investigates the kinds of social institution that reproduce whatever habits, dispositions or modes of reasoning are involved in acts of trust: this work develops theoriesofsocialcapital. A recurring question in these literatures is whether a society which organizes its economic life through markets is capable of reproducing the trust on which those markets depend. In this paper, we look at these themes in relation to the writings of three eighteenth-century philosopher-economists: David Hume, Adam Smith, and Antonio Genovesi. (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)