A peculiar arrogance accrues to people who cannot recognize the diversity of human impulses, and who feel superior because they do not lapse into behaviors that don’t tempt them in the first place. People disgusted by sexual predators say smugly that they don’t pursue the sexual favors of children, without acknowledging that they don’t find children sexually attractive. Those who do not tend toward chemical dependency express disdain for addicts; people with small appetites patronize the morbidly obese.