Self-categorization theory addresses the problem of the psychological group. Are there such things as psychological groups? How do they form? How is a collection of individuals able to act, think, and feel as a group, collectively, as if, in the extreme, the group members shared a common mind? It is taken for granted that human beings are individual persons, that they have unique personalities and differ from other individuals, but it is also known that they belong to social groups and that these social groups can have a psychological reality for their members. People do not just describe others as belonging to groups, they describe themselves as groups (not as if they were groups, but as groups). They talk about “we” and “us” as well ...