Sacred values. A survey posing tough choices revealed that when it comes to violent conflict, people don't weigh pros and cons.

Survey Says: War Is the Irrational Choice

John is a Science contributing correspondent.

How many lives would you be willing to sacrifice to remove a murderous dictator like Saddam Hussein? Most of the models that researchers use to study conflicts like the Iraq war assume that civilians and leaders make a rational calculation: If the total cost of the war is less than the cost of the alternatives, they will support war. But according to a new study, those models are wrong. Surveys of people in the Israeli-Palestinian conflict and other violent situations suggest that participants consistently ignored quantifiable costs and benefits, relying instead on "sacred values." The finding could lead to better predictions of when conflicts will escalate to violence.

Models of rational behavior predict many of society's patterns, such as the prevalence of tax evasion and union strikes. But seemingly irrational behaviors like war—in which the measurable costs often far outweigh the measurable benefits—have stumped researchers going back to Charles Darwin. The prospect of crippling economic burdens and huge numbers of deaths doesn't necessarily sway people from their positions on whether going to war is the right or wrong choice. One possible explanation is that people are not weighing the pros and cons at all, but rather using a moral logic of "sacred values"—convictions that trump all other considerations—that cannot be quantified.

To try to capture people in the act of making such decisions, psychologist Jeremy Ginges of the New School for Social Research in New York City and anthropologist Scott Atran of École Normale Superieure in Paris challenged people around the world with a series of difficult questions.

They started by surveying 656 Israeli settlers in the West Bank. The researchers asked the settlers about the hypothetical dismantlement of their settlement as part of a peace agreement with Palestinians. Some subjects were asked about their willingness to engage in nonviolent protests, whereas others were asked about violence. Besides their willingness to violently resist eviction, the subjects rated how effective they thought the action would be and how morally right the decision was. If the settlers are making the decision rationally, in line with mainstream models, their willingness to engage in a particular form of protest should depend mostly on their estimation of its effectiveness. But if sacred values come into play, that calculus should be clouded.

When it came to nonviolent options such as picketing and blocking streets, the rational behavior model predicted settlers' decisions. But in deciding whether to engage in violence, the settlers defied the rational behavior models, the researchers report today in the Proceedings of the Royal Society B. Rather than how effective they thought violence would be in saving their homes, the settlers' willingness to engage in violent protest depended only on how morally correct they considered that option to be.

In a series of follow-up surveys of U.S. college students and citizens in Nigeria, the researchers confronted subjects with hypothetical hostage situations. They were asked if they would approve of a solution—which was either diplomatic or violent—for freeing the prisoners. The chance of success varied in terms of the number of hostages who might die. For example, in one version of the survey, subjects were told that 200 hostages would likely be saved by a military rescue but that there was a two-thirds chance that all would die.

The results revealed again that when people weighed the decision to engage in violence, they were insensitive to the quantifiable costs and benefits—the number of deaths—and were swayed instead by the chance of saving lives, even if it was a poor gamble. For nonviolent actions, their decisions were dictated by the actual number of lives saved. "Decisions about diplomacy were hypersensitive to quantity," the researchers note, maximizing the number of lives likely to be saved. "It is interesting to note that we did not find much in the way of gender effects," the researchers add. Only in the survey of Israeli settlers were men more supportive of violence.

"In addition to the idea sounding right to me, I think that the paper does mobilize some nice evidence to support the case" that morals trump reason when it comes to violent conflict, says Michael Spagat, an economist at Royal Holloway, University of London. For example, if people really were rational about their decision to support or oppose the Iraq War, then they should be weighing the death toll carefully. "If I think that deposing Saddam Hussein is worth 50,000 lives but no more," he says, "then I should flip when I discover that it has cost hundreds of thousands of lives. But my sense is that hardly anyone actually behaves this way." However, Spagat says that the study is limited by its reliance on hypothetical situations. "Moral posturing is cheap," he says, and people are often poor predictors of their own behavior, especially in life-or-death situations.

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