The "motive cocktail" in altruistic behaviors

Prosocial motives such as social equality and efficiency are key to altruistic behaviors. However, predicting the range of altruistic behaviors in varying contexts and among different individuals proves challenging if we limit ourselves to one or two motives, as most previous studies have done. Here we demonstrate the numerous, interdependent motives in altruistic behaviors and the possibility to disentangle them through behavioral experimental data and computational modeling. In one laboratory experiment (N=157) and one pre-registered online replication (N=1258) across 100 different situations, we found that both third-party punishment and helping behaviors aligned best with a model of seven socioeconomic motives, referred to as a "motive cocktail", including two compound motives. For instance, the "inequality discounting" motives imply that individuals, when confronted with costly interventions, behave as if the inequality between others barely exists. The motive cocktail model also provides a unified explanation for a range of phenomena in the literature.