The Role of Multiple Social Categorisation in Promoting the Inclusion in the Human Group of Outgroup Members

This dissertation examines social cognitive processes that promote perceived inclusion of outgroup members in the human group. We first review the literature on social categorization, highlighting the role of multiple and complex categorisations, as social cognitive processes reducing intergroup prejudice. Then, we review research on dehumanisation, addressing antecedents and consequences of this tendency to exclude the “others” from the human group, assessing that research is needed to address the construens role of categorisation in including outgroups in the human group. The first line of research pursued in this contribution investigates the effectiveness of multiple categorisation as a human-enhancing mechanism towards outgroups at stake. Study 1 shows that perceiving members of a rival University along multiple categorical dimensions enhances the tendency to attribute them human traits. Study 2, involving a highly threatening outgroup, that is, immigrants, goes further beyond previous findings showing that multiple categorisation increases not only attribution of human traits to the target, but also supports for policies in defense of outgroup members’ health. Furthermore, de-categorisation as well as perceived threat from immigrants explains the relationship between categorisation and their inclusion in the human group. The second line of research extends the issue of social inclusion of outgroups, through attribution of humanness, by investigating counter-stereotypical (vs. stereotypical) expectations of others. Across three studies we provide evidence that counter-stereotypical vs. stereotypical category combinations elicits more positive and less stereotypical judgments towards different outgroups and more interestingly, the attribution of higher humanness to unrelated outgroups. Furthermore, the extension of humanising outcomes to different discriminated outgroups is explained by an increase of cognitive flexibility, such as the inhibition of reliance on heuristic thoughts. In the general discussion, we highlight the relevance of our findings in the contexts of impression formation, groups perception and intergroup relationships.