Many different factors enter into riots and other forms of social violence. On many occasions, particularly in the early stages, the aggression is impulsive rather than instrumental. Generally speaking, these “expressive” acts are responses to aversive conditions, but they are also affected by prior learning, strength of inhibitions against aggression in the specific situation, the presence of appropriate situational cues, and also the feeling of being able to cope with the aversive conditions. Social comparisons contribute to the unpleasant situations, creating a predisposition to aggression. In analyzing the role of these comparisons, it is important to specify just what groups serve as reference groups. It is suggested that unfavorable comparisons with one's own kind are particularly import