“I had seen nothing sacred, and the things that were glorious had no glory and the sacrifices were like the stockyards at Chicago if nothing was done with the meat except to bury it.”—Ernest Hemingway, A Farewell to Arms

The revival of parochial nationalism in tandem with the spread of transnational terrorism has fragmented social consensus across the world. Governments and peoples are struggling to understand what to do to get along without constant conflict, or even to see if that is possible anymore. A question that drives my colleagues and me is: Can science be of any help? And here I want to focus on one particular contribution from social science: research into how sacred values can ratchet up conflict, and what might be done about it.

Current forms of seemingly intractable political conflict—over the wall in America, Brexit in Britain, the Yellow Vests in France, Catalonian Independence in Spain—appear to share two critical features of more violent enduring conflicts, such as the Israel-Palestine dispute or the fight with ISIS and its ilk, which our interdisciplinary research teams of scientists, policymakers and artists at Artis International have been exploring in depth for more than a decade: entrenchment of issues, however material to begin with, in appeal to the uncompromising nature of so-called “sacred values” that people believe in, like God and country; and the belief that the one side, because of its antagonistic values, wants to exclude the other side from social or political life, or even from life itself.

With support from Minerva Research Initiative of the U.S. Department of Defense and National Science Foundation, we recently published the first neuroimaging study of a radicalizing population. The research used ethnographic surveys and psychological analysis to identify 535 young Muslim men in and around Barcelona—where ISIS-supporting jihadis killed 13 people and wounded 100 more in the city center in August 2017.

Half of these young men (267) scored higher that the other half (268) on all measures of vulnerability to recruitment into violent extremism. From the more vulnerable group, 38 men, second-generation immigrants of Moroccan origin who had already "expressed a willingness to engage in or facilitate violence associated with jihadist causes," agreed to have their brains scanned.

The young men selected for the neuroimaging study then played a ball-throwing game (Cyberball) with fellow Spaniards, and half of them were abruptly and deliberately excluded from being passed the ball. Their brains were then scanned while asking them questions about behavior and policies they considered sacred and inviolable (e.g., forbidding cartoons of the Prophet, preventing gay marriage) as well non-sacred but important values (e.g., women wearing the veil, unrestricted construction of mosques).

As our previous research with populations on five continents indicated (from Lowland Maya in Guatemala devoted to preserving their forest, to fighters in Indonesia devoted to militant Jihad), sacred values are preferences for which no material compromise is possible, which are immune, or strongly resistant, to costs or consequences and risks or rewards, to temporal and spatial discounting (what is distant in space or time can be far more important than the here-and-now, as with Jerusalem or the Second Coming for true believers), and where standard "business-like" negotiations tend to fail. Sacred values tend to be associated with unconditional cooperation for those who hold to such values as well as intractable conflict with those who don’t. Results showed that the neurological impact of being excluded meant that issues they had previously considered non-sacred became far more important and were now deemed similar to those considered "sacred" and worth fighting and dying for.

These findings suggest that sacralization of values interacts with willingness to engage in extreme behavior in populations vulnerable to radicalization. In addition, social exclusion appears to be a relevant factor motivating violent extremism and consolidation of sacred values. If so, counteracting social exclusion and sacralization of values should figure into policies to prevent radicalization.

In previous work in Iran, we found that sanctions (a more general political sense of exclusion) ramped up belief in the nuclear program as a sacred value, as well as actions associated with the program (e.g., increased enrichment and production of centrifuges). Note that sacred values can be religious (as with ISIS) or secular (as with the Marxist-Leninist PKK), although in the Iran case we found the sacralization of the nuclear program also became bound up with religion (among 11–13 percent of the population—mostly rural religious supporters of the hardliners—in our two successive studies).

Sacred values seem to be associated with areas of the brain involved in rule-bound behavior. That is, when sacred values are in play (versus non-sacred values) there is inhibition of deliberative reasoning in favor of rapid, duty-bound responses (we have another neuroimaging study that we presented at a previous Minerva conference, which clearly shows this among supporters of an al-Qaeda affiliate, Pakistan's Lashkar-e-Taiba, in their expressed willingness to fight and die for those values).

The brain research also complements, and replicates, another recent study by our research team at the front line with combatants in Iraq (ISIS, PKK, Sunni militia, Peshmerga, Iraqi Army). There, we show that willingness to fight and die (which can be measured behaviorally but also verified in terms of casualties, time at the front, etc.) is greatest for those who believe they are fighting for sacred values, and who also perceive "spiritual strength" (whether of their own group, allies, or enemies) as more important than material strength (manpower and firepower).

This research teases out aspects of a “devoted actor paradigm,” which we first presented to the National Security Council at the White House when Artis was formed in 2006. The aim was to bring together academic researchers and policymakers as a way of getting a handle on value-driven violence (as opposed to standard rational-actor/cost-benefit models of conflict), and more generally to figure out ways to reduce violence so as to enhance national and international security.

A key finding of this research for policymakers, whether in defense and war planning or in social programs aimed at preventing violence, is that when matters that are believed to be sacred are involved, people cannot be swayed from defense, or even offensive pursuit, of their beliefs with carrots or sticks, as with ISIS. People who are willing to sacrifice everything, including their lives—the totality of their self-interests—will not be lured away just by material incentives or disincentives such as pay, promotion or punishment. That is one reason why, ever since World War II, on average, revolutionary and insurgent movements have emerged victorious with as little as 10 times less firepower and manpower than the state forces arrayed against them.

Moreover, enticements or threats to compromise or abandon values that have become sacralized, usually backfire when competing sacred values are involved, leading to enduring conflict, as we find in the case of Palestine and Israel (Palestinians’ right of return versus Israelis’ right to settle in Greater Israel), the abortion standoff, gun rights and now the recently sacralized issue of immigration that has accompanied intense political polarization (and mutual feelings of attempted marginalization by the other side).

How then might conflicts involving sacred values be resolved? One way is by recognizing the other side’s sacred values wherever possible but offering reframing, reinterpretations and alternative pathways for their realization (as with religious commandments and canons). This, for example, is how Salafi preachers sometimes manage to dissuade suicide bombers from their course. Efforts at reinterpretation are also evident in the current maneuvering over the meaning of a border “wall.” The alternative is to sunder the fused social networks in which those values are embedded, usually by trying to utterly defeat and destroy the opposition by expending orders of magnitude greater effort and might—an alternative that may be unavoidable in some cases, as with Nazi Germany or ISIS.

But our brain study suggests that perhaps the most promising way of avoiding radicalization and intractable conflict is to prevent antagonistic values from becoming sacred in the first place. And for that, it may be best to work against social marginalization (and political polarization), so that standard approaches using material incentives and disincentives and the language of compromise might still have a chance to work, and other less belligerent and more tolerant values can still compete for devotion. “The intellectual,” explained France’s Raymond Aron over 60 years ago, “must try never to forget the arguments of the adversary, or the uncertainty of the future, or the faults of his own side, or the underlying fraternity of ordinary men everywhere.”

And in this Age of Rage, science, too, may help sheathe the arrows of fire.