The theory of group evolutionary strategies described in A People That Shall Dwell Alone: Judaism as a Group Evolutionary Strategy (MacDonald 1994; hereafter PTSDA) argued that Judaism may be understood mainly as a cultural invention, maintained by social controls that act to structure the behavior of group members and characterized by a religious ideology that rationalizes ingroup behavior both to ingroup members and to outsiders.
Although evolved mechanisms of group cohesion are also important, it was shown that social controls acting within the group were able to structure the group to facilitate ingroup economic and political cooperation and resource competition with outgroups, erect barriers to genetic penetration from outside the group, and facilitate eugenic practices aimed at producing high intelligence and high-investment parenting ideally suited to developing a specialized ecological role within human societies. Because of these traits, and particularly an IQ that is at least one standard deviation above the
Caucasian mean, Judaism has been a powerful force in several historical eras.
The proposal that Judaism may be usefully conceptualized as a group evolutionary strategy suggests that anti-Semitism be defined as negative attitudes or behavior directed at Jews because of their group membership. This is a very broad definition—one that is equally applicable to anti-Jewish attitudes in any historical era. It is also consistent with a very wide range of external processes contributing to anti-Semitism in a particular historical era, and also with qualitative changes in the nature of anti-Jewish attitudes or the institutional structure of anti-Semitism at different times and places.