We live in a world of widespread awareness of diversity. The variety of ethnicities, cultures, world views, and politics is common to anyone who takes advantage of media, communications, and travel technologies. Some diversities are quite trivial and merely provoke a smile or a shake of the head. But differences in those beliefs that guide our lives, that make us what we are - these are another matter. They are indeed the stuff of arguments, manifestos, estrangements, revolutions, and wars. Why is this so? In a way, this book is an answer to that question.