Perhaps the most important function of the culture of childhood is to teach children how to get along with peers. Children practice that constantly in social play. To play with another person, you must pay attention to the other person’s needs, not just your own, or the other person will quit. You must overcome narcissism. You must learn to share. You must learn to negotiate in ways that respect the other person’s ideas, not just yours. You must learn how to assert your needs and desires while at the same time understanding and trying to meet the needs and desires of your playmate. This may be the most important of all skills that human beings must learn for a successful life. Without this ability it is not possible to have a happy marriage, true friends, or cooperative work partners.