An economic interpretation of Epictetus's precept of 'Taking away aversion from all things not in our power' consists of extending the do- main of indifference beyond its boundaries under non-ethical preferences, so as to yield indifference between outcomes differing only on things out- side...

In evolutionary models of indirect reciprocity, reputation mechanisms can stabilize cooperation even in severe cooperation problems like the prisoner's dilemma. Under certain circumstances, conditionally cooperative strategies, which cooperate iff their partner has a good reputation, cannot be...

There is continuing debate about what explains cooperation and self-sacrifice in nature and in particular in humans. This paper suggests a new way to think about this famous problem. I argue that, for an evolutionary biologist as well as a quantitative social scientist, the triangle of two...

We study the coevolution of cooperation, preferences and cooperative signals in an environment where individuals engage in a signaling-extended prisoner's dilemma. We identify a new type of evolutionary equilibrium - a transitional equilibrium - which is constituted and stabilized by the dynamic...

We study the coevolution of cooperation, preferences, and cooperative signals in an environment where individuals engage in a signaling-extended prisoner's dilemma. We prove the existence of a cooperative equilibrium constituted by a (set of) limit cycle(s) and stabilized by the dynamic...

A distributed system model is studied, where individual agents play repeatedly against each other and change their strategies based upon previous play. It is shown how to model this environment in terms of continuous population densities of agent types. A complication arises because the...

We study environments in which agents are randomly matched to play a Prisoner's Dilemma, and each player observes a few of the partner's past actions against previous opponents. We depart from the existing related literature by allowing a small fraction of the population to be commitment types....

We investigate the welfare effect of increasing competition in an anonymous two-sided matching market, where matched pairs play an infinitely repeated Prisoner's Dilemma. Higher matching efficiency is usually considered detrimental as it creates stronger incentives for defection. We point out,...

Intelligence and personality significantly affect social outcomes of individuals. We study how and why these traits affect the outcome of groups, looking specifically at how these characteristics operate in repeated interactions providing opportunity for profitable cooperation. Our experimental...