It's easy to think that the Islamic State in Iraq and Syria (ISIS) is some sort of evil, mediaeval cancer that somehow has resurfaced in the modern world. The rest of us are pursuing happiness, and here comes this fundamentalist anachronism, spreading death.
But in his book Not In God's Name: Confronting Religious Violence, the brilliant philosopher Rabbi Jonathan Sacks argues that ISIS is in fact typical of what we will see in the decades ahead.
The 21st century will not be a century of secularism, he writes. It will be an age of desecularisation and religious conflicts.
Part of this is demographic. Religious communities produce lots of babies and swell their ranks, while secular communities do not. The researcher Michael Blume looked back as far as ancient India and Greece and concluded that every non-religious population in history has experienced demographic decline.
Humans also are meaning-seeking animals. We live, as Mr Sacks writes, in a century that "has left us with a maximum of choice and a minimum of meaning". The secular substitutes for religion - nationalism, racism and political ideology - have all led to disaster. So many flock to religion, sometimes - especially within Islam - to extremist forms.
This is already leading to religious violence. In November last year, just to take one month, there were 664 Islamist attacks in 14 countries, killing a total of 5,042 people. Since 1984, an estimated 1.5 million Christians have been killed by Islamist militias in Sudan.
Mr Sacks emphasises that it is not religion itself that causes violence. In Encyclopedia Of Wars, Charles Phillips and Alan Axelrod surveyed 1,800 conflicts and found that less than 10 per cent had any religious component at all.
Rather, religion fosters groupishness, and the downside of groupishness is conflict with people outside the group. Religion can lead to thick moral communities, but in extreme forms it can also lead to what Mr Sacks calls pathological dualism, a mentality that divides the world between those who are unimpeachably good and those who are irredeemably bad.
The pathological dualist can't reconcile his humiliated place in the world with his own moral superiority. He embraces a politicised religion - restoring the caliphate - and seeks to destroy those outside his group by apocalyptic force. This leads to acts of what Mr Sacks calls altruistic evil, or acts of terror in which the self-sacrifice involved is thought to confer the right to be merciless and unfathomably cruel.
That's what we saw in Paris last week.
Mr Sacks correctly argues that we need military weapons to win the war against fanatic groups like ISIS, but we need ideas to establish a lasting peace. Secular thought or moral relativism is unlikely to offer any effective rebuttal. Among religious people, mental shifts will be found by reinterpreting the holy texts themselves. There has to be a Theology of the Other: a complex biblical understanding of how to see God's face in strangers. That's what Mr Sacks sets out to do.
The great religions are based on love, and they satisfy the human need for community. But love is problematic. Love is preferential and particular. Love excludes and can create rivalries. Love of one scripture can make it hard to enter sympathetically into the minds of those who embrace another.
The Bible is filled with sibling rivalries: Ishmael and Isaac, Esau and Jacob, Joseph and his brothers. The Bible crystallises the truth that people sometimes find themselves competing for parental love and even competing for God's love.
Read simplistically, the Bible's sibling rivalries seem merely like stories of victory or defeat - Isaac over Ishmael. But all three Abrahamic religions have sophisticated, multilayered interpretive traditions that undercut fundamentalist readings.
Alongside the ethic of love there is a command to embrace an ethic of justice. Love is particular, but justice is universal. Love is passionate, justice is dispassionate.
Justice demands respect of the other. It plays on the collective memory of people who are in covenantal communities: Your people, too, were once vulnerable strangers in a strange land.
The command is not just to be empathetic towards strangers, which is fragile. The command is to pursue sanctification, which involves struggle and sometimes conquering your selfish instincts. Moreover, God frequently appears where he is least expected - in the voice of the stranger - reminding us that God transcends the particulars of our attachments.
The reconciliation between love and justice is not simple, but for believers the texts, read properly, point the way. Mr Sacks' great contribution is to point out that the answer to religious violence is probably going to be found within religion itself, among those who understand that religion gains influence when it renounces power.
It may seem strange that in this century of technology, peace will be found within these ancient texts. But as Mr Sacks points out, Abraham had no empire, no miracles and no army - just a different example of how to believe, think and live.
NEW YORK TIMES
A version of this article appeared in the print edition of The Straits Times on November 18, 2015, with the headline 'Finding peace within the holy texts'. Print Edition | Subscribe
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