Book excerpt: In a frank and unpretentious series of letters addressed to a teenage granddaughter, this highly original book teaches us to know and understand the world we live in and its rules, and how to behave in it. In these thirty letters, Alan Macfarlane answers his granddaughter's questions about how the world works, how it got to be as it is, what it could be, and where she fits in. Lily's enquiries range from the intimate, personal and moral to the political, social and philosophical. What is the nature of good and evil? What is religion? How can I be truly me? Is right and wrong the same wherever you are? What is beauty? Does there have to be torture? Does money matter? Is knowledge always good? What is progress? What is truth? What is sex? Is democracy a good idea? These are just a few of the questions. In responding to Lily's challenging problems, Alan Macfarlane, from a lifetime's experience as a historian, anthropologist and teacher, ranges through history and across the world's cultures. Her questions are timeless. His answers add up to a classic.