If it wasn’t the philosophical equivalent of the Gunfight at the O.K. Corral, the distinguished journalists who waited in eager anticipation around the square-shaped table at the offices of the Pew Forum on Religion and Public Life on Washington’s M Street in late October may well have anticipated fireworks. The Washington Post‘s Sally Quinn, the Economist‘s Peter David, the Guardian’s Timothy Garton Ash, the Washington Examiner‘s Michael Barone, and a handful of others had been invited to witness an unusual public debate between Christopher Hitchens, enfant terrible of the New Atheism and author of the best-seller God Is Not Great: How Religion Poisons Everything, and his brother, Peter Hitchens, author of the more recent The Rage Against God: How Atheism Led Me to Faith. The two brothers had clashed in public debate before, often acrimoniously, but this event was special: it was the first major discussion between them in public since Christopher, 61, was first diagnosed with metastatic (usually fatal) esophageal cancer in June 2010. Would natural fraternal sympathy prevail over the two men’s deep, and long-lasting, philosophical disagreement?

There were no fireworks in the large meeting room on M Street, just flashes of wit (mostly from Christopher), seriousness (mostly from Peter), and the sense that this encounter, between an ailing champion of unbelief and his still-energetic brother, might turn out to be historical. Nobody could fail to observe that Christopher, in a pale-blue open-neck shirt characteristically left unbuttoned at the top two buttons, was completely bald from chemotherapy treatment and understandably tired-looking. His brother, Peter, 59, also wearing a tieless shirt of very pale blue color, looked much younger and fresher than Christopher, though only some 19 months separate their birthdays. The disagreements, of course, surfaced early at the conversation, yet there was a surprising overlap in attitudes between the two men. Skillfully moderating the event, Michael Cromartie, vice president of the Ethics and Public Policy Center, gracefully referred to Christopher Hitchens’s reputation, in spite of his strong opinions, of being a lifelong loyalist to his personal friends. He quoted a reviewer of Hitchens’s latest book, an autobiography called Hitch-22: A Memoir, as saying of Christopher that he was “one of the most purely alive people on the planet.” Some of the audience must have wondered at that choice of words; with characteristic bluntness, the older Hitchens brother has told recent audiences flatly that he was “dying.”

THE PEW FORUM had posed the debating question to the two brothers as this: “Can Civilization Survive without God?” Christopher opened with a short statement, in which he, perhaps surprisingly, invited his listeners to contemplate what he felt had been the sad demise of a once-powerful notion, that of “Christendom.” This word, Christopher said, used to be employed by people without irony. It meant, he said, that “there was a Christian world. It had been partly evolved, partly carved out by the sword, partly defended by the sword, at some points giving way, at other times expanding. But it was a meaningful name for a community of belief and value that endured for many, many centuries-and has many splendors to its name.” Now, he insisted, it was “all gone,” leveled by the madness of World War I. Its loss, he insisted, had left all kinds of questions about civilization and culture. “We’ve had to wrestle,” he said, “for a very long time with the idea, what will we do about civilization; what will we do about values, ethics, morals; how will we teach them; how will we learn to live with one another in the absence of any real religious authority, any credible one, any one that’s worthy of the name, worthy of respect? This absence has been felt for a very, very long time, long before I was able to start writing about it.”

Peter didn’t demur at this description of the great loss. Rather, he insisted, what was civilization? He felt he knew what it wasn’t, like his experience of arriving in Mogadishu shortly before the arrival of the U.S. Marines in 1993 and experiencing the shock of a society that had broken loose from all constraints of civilization; no passport control, baggage claim, or the normal paraphernalia of international travel. Peter said that he’d instantly had to hire AK-47-equipped bodyguards and, before going to sleep on the concrete floor of a compound rented by a German TV crew, had listened “to the cries of dying people and the chatter of gunfire outside and hearing, in effect, what would have happened to me if I hadn’t found my way into the German compound.” For Peter Hitchens, the thing that struck him about societies that were not intolerable to live in was “the rule of law.”

He added, “This seems to me to be the distinction between a tolerable free society and one which is not, which is the most decisive.”

Yet even in the English suburb of Alverstoke, near Portsmouth in England where the Hitchens brothers had grown up, a plague of violence and even barbarism had crept into the community, Peter said, with one ordinary citizen being kicked to death by hooligans whose destruction of his yard fence he had attempted to stop. “How has this decline in civilization come about?” Peter asked. “Well,” he said, “I think it has come about at least partly-and I’m not a single-cause person-but at least partly because there is no longer in the hearts of the English people the restraint of the Christian religion, which used to prevent this sort of behavior.”

Claiming to be shocked to hear of the Alverstoke incident, Christopher riposted that quite as frightening horrors were occurring in cities like Glasgow in the 1950s, at a time when the authority of the Church of England was certainly greater than in subsequent years. In fact, in Glasgow, Christopher said, “people would kill you over what kind of Christian you were, as a matter of fact.” Of course, they did, said Peter, because of the problems of Catholic and Protestant sectarianism. “But in terms of the lives which people led, the way in which they behaved towards their neighbors, the way in which children were brought up, the manners which people displayed, I don’t think you will find that the effect of Christian upbringing was small in the 1950s or 1960s.” What had happened, Peter asserted, was that English society had been invaded “by trash culture and all that kind of teaching.”

WHEN JOURNALISTS WERE INVITED to ask questions, NPR’s Barbara Bradley Hagerty inquired gently if Christopher’s illness had led to a greater warmth between the two brothers. Almost visibly bristling over the suggestion that intimations of mortality might have softened his attitudes toward religion, Christopher responded, “I mean, if you want to know, if anything, my contempt for the forced consolation of religion has increased since I became aware that I probably don’t have very long to live.” He added that he found the idea of deathbed conversions “wholly contemptible.” Perhaps trying to tamp down any tension, Peter shortly afterwards waded in with a comment of his own: “it would be quite grotesque” to imagine that acquiring cancer might enable one “to see the merits of religion. It’s just an absurd idea.”

Washington Post columnist Michael Gerson wondered about “the challenge of Friedrich Nietzsche,” who argued that, in the absence of transcendent values, all one was left with was “ferocious human will.” Christopher replied that he thought the religious impulse was merely “an expression of the will to power.” “Who could deny it?” he said, all but challenging his listeners to respond.

Peter responded. “I think that you would be hard put to claim,” he said, “that the Christian Gospels gave you a license to order people about. And it seems odd that the center of Christian worship is someone who is indeed tortured to death by the powerful.” Peter added that he thought Nietzsche had focused on an issue atheists seldom were honest about: they wanted liberation from constraints. “This constantly comes up,” he said, “and immediately swirls down the circle of the atheists’ refusal to accept that there is actually no absolute right and wrong if there is no God and that therefore, they are liberated.” Besides, Peter added, how on earth could atheists explain conscience if there were no transcendent moral values? “If morality evolves, then morality changes,” he said. “Then the things of which we most strongly disapprove now could be things which are permitted later, in which case it’s not really morality, as far as I’m concerned. And who’s evolving it?” Christopher ignored this sally, but came back later with one of his own. “If anything could prove what I so much believe,” he said, “which is that we are not made by God and never were and could not have been, but that many, many gods have been made by men and women and it is precisely the other way around, the basic claim of materialism — if nothing else could persuade me of that obvious truth, the behavior of religion itself would be enough.”

Christopher conceded that, as far as civilization was concerned, people hadn’t yet conquered the problem of alienation or of anomie or of spiritual waste or of the fear of death. “That,” he said, had “to be worked on.” There was, he said, also a continuing problem of “moral relativism.” He nevertheless insisted, “But I don’t think it’s really true to say that we live less civilized a life than those of our predecessors who felt that there was a genuine religious authority that spoke with power.”

GIVEN A CHANCE both to sum up his views and to admit to any doubts about his faith he might have had, Peter said that the moments of doubt occurred often when he was reading either the Old Testament or the Letters of Paul, because, he said half-apologetically, “as you will see, I’m not terribly orthodox in my belief.” He insisted that religion was “absolutely necessary” in order for a person to be moral. “Morality,” he said, “is what you do when you think nobody is looking.” “This tremendous civilization in which we live,” he said, “which has been bequeathed to us and which in my country we’re determined not to bequeath to our own children, is the most extraordinary piece of good fortune, if nothing else. And it does seem to me derived — as I say, this combination of order and liberty almost unique in human history and unique on the face of the planet — does arise, actually, from Protestant Christianity.” To this idea, Christopher riposted. “Morality is not learned by orders. It’s acquired by experience, by moral suasion, and by comparing and contrasting different ways of resolving these questions.”

Christopher Hitchens, however, repeatedly expressed gratitude for the greetings he had received from Christian well-wishers expressing, as he said, “solidarity” with him. His pugnacity during the debate was as evident as ever, yet he showed an unexpectedly conciliatory attitude toward the faith that he had rejected as a child, and to which Peter, having raged through much of his life as an atheist, had returned.

Asked if he could think of anything positive to say about religions, Christopher replied, “The greatest contribution of Christianity in my life is the reminder of the complete ephemerality of human power, and indeed of human existence — the transience of all states, empires, heroes, grandiose claims, and so forth. That’s always with me, and I dare say I could have got that from Einstein — I would have — and from Darwin, too. But the way I got it and the way it’s implanted in me is certainly by Christianity.”

Civilization certainly survived the debate on M Street. So indeed did God.