This paper presents a formal theory of reciprocity. Reciprocity means that people reward kind actions and punish unkind ones. The theory takes into account that people evaluate the kindness of an action not only by its consequences but also by the intention underlying this action. The theory...

According to the Framework Convention on Climate Change, global collective action is needed to stabilize "greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous [our emphasis] anthropogenic interference with the climate system." The Framework Convention thus...

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...

Are humans intuitively cooperative, or do we need to deliberate in order to be generous to others? The Social Heuristics Hypothesis (SHH) proposes that fast instinctive decision making promotes cooperation in social dilemmas. In this paper, we conduct a novel time-pressure experiment to shed...

We use laboratory experiments to study the causal effects of favorable and unfavorable competitive market experience on cooperation in a subsequent social dilemma game. The issues we study are part of the broader topic of whether there are behavioral spillovers between different spheres of...

Understanding the roots of human cooperation among strangers is of great importance for solving pressing social dilemmas and maintening public goods in human societies. We study the development of cooperation in 929 young children, aged 3 to 6. In a unified experimental framework, we examine...

We investigate in a laboratory setting whether revealing information on intelligence affects behavior in games with repeated interactions. In our experimental design we communicate information on the cognitive ability of both players. We use three stage games: Prisoners' Dilemma (PD) and two...

Peer observation can influence social norm perceptions as well as behavior in various moral domains, but is the tendency to be influenced by and conform with peers domain-general? In an online experiment (N = 815), we studied peer effects in honesty and cooperation and tested the...

We study the development of cooperation in 929 young children, aged 3 to 6. In a unified experimental framework, we examine pre-registered hypotheses about which of three fundamental pillars of human cooperation – direct and indirect reciprocity, and third-party punishment – emerges earliest...