This groundbreaking and eloquently written book explains how and why people are wedded to the notion that they belong to differing human kinds--tribe-type categories like races, ethnic groups, nations, religions, casts, street gangs, sports fandom, and high school cliques.

Democrat and Republican. Meat Eaters and Vegetarians. Black and White. As human beings we sort ourselves into groups. And once we identify ourselves as a member of a particular group-say, Red Sox fans-we tend to feel more comfortable with others of our own kind, rather than, say, Yankees fans. Yet we all belong to multiple groups at the same time-one might be a woman, a mother, an American, a violinist. How do we decide which identities matter and why they matter so much? And what makes us willing to die for, or to kill for, a religion, a nation, or a race?
In this award-winning book,...