But so can an overworked high-school teacher who cannot dedicate the needed energy to troubled students; magazines that promote unrealistic body images; sermons from clergy who believe that God does not forgive everyone; or even a stranger acting rudely on a train. All of these actors have their own ideas and motivations, and they are all manipulating our perspectives – and our moods – every day.
有人说Facebook替用户选择可能危及用户的心理健康。但无法给予问题学生必要关注的劳累过度的高中老师；宣传不切实际体型的杂志；认定上帝不会宽恕所有人的布道的神职人员；甚至是在火车上举止粗鲁的陌生人都可能发挥同样的作用。上述各方具有各自的想法和动机，并且每时每刻都在影响我们的情绪和看法。