Book excerpt: Happy Lives, Good Lives offers a thorough introduction to a variety of perspectives on happiness. Among the questions at issue: Is happiness only a state of mind, or is it something more? Is it the same for everyone? Is it under our control, and if so, to what extent? Can we be mistaken about whether we are happy? What role, if any, does happiness play in living a good life? Is it sometimes morally wrong to pursue happiness? Should governments promote happiness through public policy? Asking and answering these questions is worthwhile not only as an intellectual exercise, but also as a means of gaining practical insight into how best to pursue a happy life.