The Double Edged Passion

In his test of this theory, Sherif started his boys playing competitive games against each other after a few days. He offered prizes such as penknives, with the losing team receiving nothing. Within days, tauntings and food fights escalated to the point that the boys refused to eat meals in the same room. The campers began playing pranks on each other, stealing each others’ flags, and behaving in a generally rotten and scurrilous manner.

This may sound like nothing more than child's play, but adults, too, respond to competition. As the anthropologist Thomas J. Schoeneman noted in 1975, witch hunts worldwide tend to follow closely after social turmoil. They peaked in Europe in the 16th and 17th centuries when churches fell under siege from science and monarchs, they peaked in Massachusetts when Puritan influence there came under intense fire, and they peaked in Washington when China and the USSR loomed as threats. Meanwhile, a paranoid Stalin was holding witch hunts of his own. This isn’t a uniquely Western phenomenon; similar, if less murderous, patterns have been observed in Africa.
Competition, then, can spur prejudice. But if you look carefully at what happened in the Sherif experiment, the boys actually started taunting each other before competitive games were introduced --though they were still happy to eat together at that point. This illustrates another psychological finding, albeit one that has only come to be fully understood only recently:  ingroup biasesreally don't take much to get started.

Henri Tajfel's minimal ingroup experiment is famed for illustrating just how little is required. He asked boys to guess how many dots were shown on a speckled slide and subsequently announced they were over- or underestimators. Next the boys distributed points (that were exchangeable for money) amongst each other. They tended to give more to those who were the same 'type' as themselves. They had spent mere minutes as a member of this transparently meaningless  ingroup, and yet were already showing favoritism! Before you wonder which type you are, and how you can spot members of the other kind so you can fleece them, know this: Tajfel decided which type they were based on a coin flip, rather than anything they actually did. The kinships of “overestimators” with other “overestimators” wasn’t just flimsy, it was completely fictitious.

Now short-changing a stranger for a few bucks is a long way from, say, burning them as a witch, or blowing them up in a market place. But then being told you're an "overestimator" is also a long way from discovering a wave of heretics threatening your way of life, or foreign soldiers patrolling the place you call home. It's amazing that such a small prod produced any response at all.

Why We Hate - What We've Learned

In 1998 a man in Laramie, Wyoming named Matthew Shepard was robbed, beaten, and left for dead. Mr. Shepard posed no threat to his attackers; he wasn’t competing with them for any resources, nor even carrying anything valuable. He was just gay. But if the antipathy motivating this violence cannot reasonably be ascribed to any very realistic threat, where did it come from?

Perhaps it was just learned. Cultures pass on many pieces of useful information to their members -- how to make fires, raise kids, win friends, and who to watch out for. People grow up hearing about the dangers of Black “pimps” and White “trash.” They read about thieving Jews (even in Dickens and Shakespeare), Arab terrorists, and a panoply of other “thems,” who are variously sneaky, pushy, violent, dishonest, or just plain disgusting. The hallmark of such cultural knowledge is that when asked, people reply “everyone knows.” For example, “everyone knows” that eating with your hands is bad manners. Here and now it’s a cultural truism. Where and when Matthew Shepard went to school, homosexuality was inexplicably on this cultural hit list.

Cultures can work quite hard on the problem of hate. The Nazis spent a great deal of energy on propaganda to convince ordinary German to view Jews as less than human. Conversely, much of the western world has spent the last half century working in the opposite direction, expending a great deal of energy to remove prejudices. It can go both ways.

Do We Hate to Feel Good?

Prejudices can be used as mental shortcuts to warn us away from liars, cheats and other no-good bastards -- that’s likely a big part of why we have them. But prejudice can also salve our hurts and bring us closer together. No, that’s not a misprint. Let me explain.