Book Summary

Berreby shows how our "tribal'' sense is a part of human nature, expressing itself in every aspect of life, effecting our thoughts, our health and our society more than we realize.

There are so many ways to sort people. We all do it, all the time. From everyday decisions (whom to invite to dinner?) to life choices (whom to marry?) to the great turning points of history (whom to war against?), we're guided by an ever-present sense, in any situation, of who belongs with whom, and what that belonging means. Everyone is part of many groups at once, of course - you might be a woman, a parent, a Republican, an American, and a Hindu. So, how do we decide which identities matter? Why do they matter so much? What makes people willing to die, or to kill, for a religion, nation, race, or caste?

In this groundbreaking book, David Berreby shows how science tackles these questions of group identity. Drawing on new findings from anthropology to neuroscience, he argues that this "tribal'' sense is a part of human nature, expressing itself in every aspect of life.

The effects run deep, shaping our lives and opportunities. Us and Them elegantly explains how this tribal sense:

 
• Alters our thoughts. Show older people a negative image of the aged, and they act more feeble. Asian women reminded of their Asian heritage did better on a math test than those who were reminded they were women. In a small room, the lone holdout against a group's opinion usually gives in and changes - even when it's obvious that the group is wrong.
  
• Affects our health. People's sense of their place in society directly links to measures of stress, depression, and cholesterol levels.
  
• Affects our society more than we realize, because it can be manipulated for good and for ill. Tribal rhetoric has made people feel that injustice and oppression are perfectly normal, for instance, while at other times, it has led them to set aside hatred in favor of reconciliation. One experimenter made a group of young summer campers into warring "tribes''; and, just as easily, he brought them back together. Us and Them explains how and why the tribal "buttons'' are pushed.

We can't live without our tribal sense. It tells us who we are and how we should behave. It frees us from the narrow confines of the self, linking us to others and the past and the future. Some condemn this instinct, as if it were only a source of evil. Others celebrate it, as if loyalty and faith were never misused. David Berreby brilliantly describes a third alternative: how we can accept and understand our inescapable tribal mind.