Benevolent characteristics promote cooperative behaviour among humans

Cooperation is fundamental to the evolution of human society. We regularly observe cooperative behaviour in everyday life and in controlled experiments with anonymous people, even though standard economic models predict that they should deviate from the collective interest and act so as to maximise their own individual payoff. However, there is typically heterogeneity across subjects: some may cooperate, while others may not. Since individual factors promoting cooperation could be used by institutions to indirectly prime cooperation, this heterogeneity raises the important question of who these cooperators are. We have conducted a series of experiments to study whether benevolence, defined as a unilateral act of paying a cost to increase the welfare of someone else beyond one's own, is related to cooperation in a subsequent one-shot anonymous Prisoner's dilemma. Contrary to the predictions of the widely used inequity aversion models, we find that benevolence does exist and a large majority of people behave this way. We also find benevolence to be correlated with cooperative behaviour. Finally, we show a causal link between benevolence and cooperation: priming people to think positively about benevolent behaviour makes them significantly more cooperative than priming them to think malevolently. Thus benevolent people exist and cooperate more

Fostering Cooperation through the Enhancement of Own Vulnerability

We consider the possibility that cooperation in a prisoner's dilemma is fostered by people's voluntarily enhancement of their own vulnerability. The vulnerability of a player determines the effectiveness of possible punishment by the other. In the "Gradual" mechanism, players may condition their incremental enhancements of their vulnerability on the other's choices. In the "Leap" mechanism, they unconditionally choose their vulnerability. In our experiment, subjects only learn to cooperate when either one of these mechanisms is allowed. In agreement with theory, subjects aiming for cooperation choose higher vulnerability levels in Gradual than in Leap, which maps into higher mutual cooperation levels