Intergroup comparison drives all religious members, but fundamentalists pursue it to extremes.

Evidence

Religious group members, as well as group members in general, make intergroup comparisons in order to confirm their belief/attitude that their religion is superior to others. If memberships in collectives is a source of information about the social self, the individuals will then seek to evaluate the social self, as they do aspects of the personal self. Intergroup comparison is one way in which individuals will assess their group and understand the collective self. Although intergroup comparison and beliefs that one’s religious faith is superior to other faiths occurs in less extreme members, fundamentalists of any faith demonstrate the extremity of this behavior (Herriot, 2009). Religious fundamentalists act in an extreme manner not only to separate themselves from others but also to reinforce their own beliefs (Herriot, 2009). Herriot (2009) cites the example of the schism between Fundamentalist Christians and Pentecostal Christians, in which Fundamentalists claim superiority because Pentecostals are seen as driven by emotions and lacking intellectual rigor. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 913