Why Do People Keep Their Promises? A Further Investigation

Abstract

A large body of evidence indicates individuals keep promises even if self-interest dictates otherwise. Two rationales have been put forth. First, promises form an emotional commitment to keep actions and deeds consistent, referred to as the commitment rationale. Second, promises change the expectations of others and not meeting others' altered expectations leads to guilt, referred to as the expectations rationale. In an investment game where a trustee may have his message to a trustor intercepted, we find that promise keeping is greater if the message is delivered than if it is intercepted, lending support for the expectations rationale. In a second implementation of the game, messages are either delivered before or after the trustor makes an investment decision. We find that whether the promise is delivered on time versus late, although relevant, is significantly less relevant in promise keeping than whether the promise is delivered on time versus not at all. Therefore, we conclude the expectations of the promisee matter even if the promise did not induce an action, further supporting the expectations rationale.

Keywords: Experimental Economics, Promises, Trust Games