Violence should permanently alter theory about and policy-making on the subject. Collins argues that violence is not frequent, contagious, chaotic, or enduring. Nor are its perpetrators especially brave, able, or willing. The cowboy cops, war lovers, hit-men, sadists, and the like who populate modern romance are largely media fabrications that make the job of understanding violence only that much more difficult. Equally deficient in this regard are the libraries of social science that locate the causes of violence either inside the perpetrators’ heads (e.g., in their frustrations, their lack of education, their “short fuses,” their rational calculations, machismo, or prejudices); that, or in structural conditions lying outside them (their alleged “culture of death,” their poverty, powerlessness, anomie, or alienation). Such accounts are what Collins calls “folk cognitions,” tales devised by expert myth-makers after battles to bring them to meaningfully satisfying conclusions. Thus,...