The role of in-group identification in infra-humanization.

People tend to infra-humanize by attributing more human essence to their in-group than to out-groups. In the present article, we focus on the attribution of primary and secondary emotions to operationalize the human essence. We propose that, in order to infra-humanize, people need to be categorized in meaningful groups. In addition, we argue that what differentiates meaningful from nonmeaningful groups is that the people essentialize, perceiving members of the group as sharing an underlying, common essence. Also, we hypothesize that participants will identify more with their in-group in the case of meaningful groups. Three types of groups were created to manipulate the meaningfulness of the categorization. Participants were either randomly assigned to a group or they chose their group as a function of their preferences for a colour or the type of career they wished to pursue. As expected, infra-humanization occurred only where the categorization's criterion was meaningful. In addition, in-group identification, but not essentialism, mediated the impact of the categorization criteria on the tendency to infra-humanize. Data also showed that infra-humanization is different from classic in-group favouritism. This is because in-group favouritism, but not infra-humanization, was observed in the situation where group membership was based on random assignment. In other words, for infra-humanization to occur mere categorization is not enough; meaningfulness is also needed. For in-group favouritism to arise, the knowledge of being part of a group is a sufficient prerequisite. The discussion focuses on conditions for reducing infra-humanization and on the relationship between in-group favouritism and out-group derogation.