Helping the ingroup versus harming the outgroup: Evidence from morality-based groups (Withdrawn Publication. See vol. 101, 2022)

The discrepancy between ingroup favoritism and outgroup hostility is well established in social psychology. Under which conditions does ingroup love turn into outgroup hate? Studies with natural groups suggest that when group membership is based on (dis)similarity of moral beliefs, people are willing to not only help the ingroup, but also harm the outgroup. The key limitation of these studies is that the use of natural groups confounds the effects of shared morality with the history of intergroup relations. In two preregistered experiments, we test the effect of morality-based group membership on intergroup behavior using artificial groups that help disentangling these effects. We use the recently developed Intergroup Parochial and Universal Cooperation (IPUC) game which differentiates between behavioral options of weak parochialism (helping the ingroup), strong parochialism (harming the outgroup), universal cooperation (helping both groups), and egoism (profiting individually). The preliminary findings suggest that morality-based groups exhibit less egoism, more weak parochialism, more universal cooperation, and less strong parochialism. These findings contradict earlier evidence from natural groups and suggest that (dis)similarity of moral beliefs is not sufficient to cross the boundary between ingroup love and outgroup hate. The third and final preregistered study aims to replicate these findings in a different cultural setting and test the mediating role of trust in this process.

Automated summary

The discrepancy between ingroup favoritism and outgroup hostility has been well established in social psychology. Studies with natural groups suggest that when group membership is based on similarity or dissimilarity of moral beliefs, people are willing to help their ingroup but harm the outgroup. However, these studies are limited by confounding factors such as shared morality and intergroup relations. Two preregistered experiments using artificial groups and the IPUC game show preliminary findings that morality-based groups exhibit less egoism, more weak parochialism, more universal cooperation, and less strong parochialism. These findings contradict previous evidence and suggest that moral beliefs alone are insufficient in explaining the transition from ingroup love to outgroup hate. The third and final preregistered study aims to replicate these findings in a different cultural setting and examine the mediating role of trust in this process.