An effective way to foster cooperation is to monitor behaviour and sanction freeriding. Yet, previous studies have shown that cooperation quickly declines when sanctioning mechanisms are removed. We test if explicitly expressing trust in players' capability to maintain cooperation after the...

In prosocial decisions, decision-makers are inherently uncertain about how their decisions impact others' utility - we call this interpersonal uncertainty. We show that people's response to interpersonal uncertainty shapes well-known patterns of prosocial behavior. First, using standard social...