Promising serves as an important commitment mechanism by operating on a potential cheater’s internal value system. We present experimental evidence on why people keep their promises, identifying three motives. First, people feel duty bound to keep their promises regardless of whether promisees expect them to do so (promising per se effect). Second, they care about not disappointing promisees’ expectations regardless of whether those expectations were induced by the promise (expectations per se effect). Third, they are even more motivated to avoid disappointing promisees’ expectations when those expectations were induced by a promise (interaction effect). Clear evidence of some of these effects has eluded the prior literature because of limitations inherent to the experimental methods employed. We sidestep those difficulties by using a novel between-subject vignette design. Our results suggest that promising may contribute to the self-reinforcing creation of trust as expectations of performance encourage promise keeping and vice versa.

中文翻译：

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承诺，期望与社会合作

通过在潜在作弊者的内部价值系统上进行操作，有前途成为重要的承诺机制。我们提供了实验证据，说明人们为何信守诺言，并确定了三种动机。首先，人们感到有义务遵守诺言，无论诺言是否期望他们遵守诺言（本身是有希望的效果）。其次，他们关心的是不要让承诺者的期望失望，无论这些期望是否是由承诺引起的（期望本身的效果）。第三，当承诺由期望（交互作用）引起时，他们更有动力避免使承诺者的期望失望。由于所采用的实验方法固有的局限性，这些作用中的某些作用的明确证据使现有文献难以理解。我们通过使用新颖的主题间小插图设计来避免这些困难。我们的结果表明，有前途的人可能会促进自我信任的建立，因为对绩效的期望会鼓励遵守诺言，反之亦然。