Before urbanization, children were viewed as economic assets to their parents. If you had a farm, they toiled alongside you to maintain its upkeep; if you had a family business, the kids helped mind the store. But all of this dramatically changed with the moral and technological revolutions of modernity. As we gained in prosperity, childhood came increasingly to be viewed as a protected, privileged time, and once college degrees became essential to getting ahead, children became not only a great expense but subjects to be sculpted, stimulated, instructed, groomed. (The Princeton sociologist Viviana Zelizer describes this transformation of a child’s value in five ruthless words: “Economically worthless but emotionally priceless.”) Kids, in short, went from being our staffs to being our bosses.