How people choose gifts is a widely studied topic, but what happens next is largely understudied. In two preregistered studies, one field experiment, and an analysis of secondary data, we show that giving gifts has a dark side, as it can negatively affect subsequent interpersonal behavior between givers and receivers. In Study 1, we found that giving a gift to one's romantic partner changes givers' interpretation of which behaviors constitute infidelity. Specifically, we found that givers (vs. nongivers) classified their questionable behaviors (e.g., sending a flirtatious text to someone other than their partner) less as a form of cheating on their partner. In Study 2, we examined how politely participants behave when delivering bad news to a friend. We found that givers (vs. nongivers) wrote significantly less polite messages to their friend. In Study 3, we tested real gifts that people give to friends and found givers (vs. nongivers) subsequently made more selfish decisions at their friends' expense. In all, our research refines the oft-cited axiomatic assumption that gift giving strengthens relationships and illuminates the potential for future research to examine how decision making can alter interpersonal, romantic relationships.

中文翻译：

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人们在送礼后会更自私吗？

人们如何选择礼物是一个被广泛研究的话题，但接下来会发生什么却在很大程度上被忽视了。在两项预先注册的研究、一项实地实验和对二手数据的分析中，我们表明送礼有阴暗面，因为它会对送礼者和接受者之间的后续人际行为产生负面影响。在研究 1 中，我们发现给自己的爱人送礼物会改变送礼者对哪些行为构成不忠的解释。具体来说，我们发现给予者（相对于非给予者）将他们的可疑行为（例如，向伴侣以外的其他人发送调情短信）归类为欺骗伴侣的形式较少。在研究 2 中，我们检查了参与者在向朋友传递坏消息时的礼貌行为。我们发现给予者（vs. nongivers）给他们的朋友写的礼貌信息要少得多。在研究 3 中，我们测试了人们送给朋友的真实礼物，发现送礼者（与不送礼者）随后做出了更多自私的决定，而牺牲了朋友的利益。总之，我们的研究完善了经常被引用的公理假设，即送礼可以加强人际关系，并阐明未来研究的潜力，以检验决策如何改变人际关系和浪漫关系。