糖心原创

Title: Why do people keep their promises?

Abstract: Sometimes people keep their promises that contradict their self-interest even in the absence of binding contracts or reputational concerns. Two dominant explanations have emerged for this behavior: (1) the avoidance of guilt due to not meeting the promisee's expectations; (2) an intrinsic preference for promise-keeping. To provide causal evidence in favor of each rationale, we design an experiment that manipulates when the promise becomes known to the promisee. Additionally, we introduce a new treatment in which, instead of allowing subjects to write free-form messages, they can only choose between two pre-written messages (one containing a promise and the other one without), which enables us to investigate whether the spontaneity of a promise could influence people's promise-keeping behavior.