In his paper Ethnicity as Cognition (2006), Rogers Brubaker held that cognitive psychology can enrich the understanding of the practices of categorisation that underpins ethnicity, nationhood and race. I shall argue that the philosophical debate concerning the different types of explanation in social sciences – the explanations based on reasons and the explanations based on causal mechanisms – can throw some light on this issue. To analyse beliefs requires use of both approaches. It can be shown with the classical opposition between an ethnic and a civic conception of national belonging which derives from a reason-based approach. The causal mechanism approach underlying cognitive psychology can offer alternative models accounting for national self-understanding, notably the prototype model of categorisation. I confront empirically these two theories – the ethnic civic dichotomy and the prototype model – using the issp data from 2003 and evidence the advantages and shortcomings of each theory.
