As with other species, human quality of life also varies with the consequences of rank inequalities—there’s a big difference between the powerful getting seated at a restaurant before you and the powerful getting to behead you if the fancy strikes them. Recall the study of thirty-seven countries showing that the more income inequality, the more preadolescent bullying in schools. In other words, countries with more brutal socioeconomic hierarchies produce children who enforce their own hierarchies more brutally.7
