Believe it.

The Twilight of Atheism: The Rise and Fall of Disbelief in the Modern World, by Alister McGrath (Doubleday, 306 pp., $23.95)

NOT long ago--just 34 years ago, to be exact--"many had come to the view that religion was on its way out," Oxford University theologian Alister McGrath writes in his highly readable new book. In 1970, it seemed that social scientists' predictions were coming true: that first the industrialized West and then the fast-industrializing remainder of the world would follow an inexorable trajectory of secularization. Both the Catholic and the mainline Protestant churches in Europe and North America were in the throes of a crisis of confidence in which church attendance declined drastically. The future of Judaism looked terminal, at least as far as the beliefs and practices of highly assimilated Western Jews were concerned. Behind the Iron Curtain lay an enormous, powerful bloc of Marxist and hence officially atheistic states, and their numbers were growing as Marxist movements metastasized to Southeast Asia, the Mideast, Africa, and Latin America. In the United States, the theology du jour maintained that God was dead. In Europe, the fashion was liberation theology, which stripped traditional Christian beliefs of their transcendence and reduced them to the utter immanence of political revolution. Ex-Beatle John Lennon invited his listeners to enter a utopian world that would be devoid of conflict because it would be devoid of God: "Imagine there's no heaven; it's easy if you try / No hell below us, above us only sky."

As we know, none of this happened. After reaching its high-water mark during the early 1970s, secularism began to fade as a cultural influence, and the past 30 years have seen a resurgence of religion of nearly every kind: New Age "spirituality," the burgeoning of evangelical and pentecostal Christianity not just in America but throughout the Third World as well, the revival of Orthodox Judaism, and, of course, the rise of militant Islam. In The Twilight of Atheism, McGrath, a former atheist himself, attempts to explain why this happened: how it came to be that atheism, the hallmark of that powerful intellectual trinity--Darwin, Marx, and Freud--whose thinking defined atheism's golden age, the 19th and 20th centuries, is now the shrunken province of a handful of learned cranks and polemicists, such as the neo-Darwinist promoter Richard Dawkins and Michael Newdow, the doctor/lawyer/professional litigant who recently challenged the phrase "under God" in the Pledge of Allegiance.

Atheism per se did not exist until modern times. The Greeks and Romans had defined an atheist not as someone who disbelieved in God but as someone who rejected the traditional gods who protected the social order. Hence Socrates was an atheist, and so, in the eyes of the pagan Romans, were the early Christians. Almost everyone in the ancient and medieval worlds believed in a deity or deities. Atheism as we now know it, McGrath explains, grew up in one specific place, Western Europe (and its outposts in America and elsewhere), as a phenomenon of a specific time, the dawn of modernity, and as a reaction against a specific religion, Christianity. The roots of atheism, McGrath suggests, lay paradoxically in that primal phenomenon of Western modernity, the Protestant Reformation. The Reformers' efforts to purify the institutional church in order to make it more concordant with their vision of Jesus' authentic teachings generated a loss of trust in institutional religion in general. Furthermore, McGrath argues that the Reformers, by focusing upon the Bible as the sole source of God's revelation, effectively desacralized both the natural world and the secular human world, which in the integralist medieval Catholic view had been equally saturated with God's sacred presence. With the Reformation, "God became an absence in the world," writes McGrath.

Secular rulers' efforts to mediate the inevitable conflicts that developed between Catholicism and Protestantism and between different strains of Protestantism by mandating religious tolerance and limiting the influence of religion in public life led many to deem religion irrelevant and religious differences risible, like the squabbles between the Big-Enders and the Little-Enders in Gulliver's Travels. Add to that the rise of Cartesian skepticism and scientific naturalism among 17th- and 18th-century intellectuals, who tried to subject supernatural claims to laboratory-style empirical proof. If you could not prove the existence of God scientifically--and who can?--He must not exist.

Nonetheless, as McGrath points out, there were few genuine atheists even among the most antinomian of Enlightenment philosophes. Even Voltaire, like many of his Enlightenment contemporaries, was a Deist, a believer in a remote watchmaker-God, and his quarrel with religion was a quarrel with what he viewed as a corrupt Church in league with a tyrannical ancien regime. Nor until the mid-19th century did many scientists, or, for that matter, many religious leaders, assume the inherent conflict between science and religion that is a standard assumption of our own time. To scientists and churchmen alike, scientific discoveries merely revealed the glory and intricacy of God's creation. (McGrath nicely demolishes as urban legend the tale of Bishop Samuel Wilberforce's sarcastically inquiring of evolutionist Thomas Huxley whether Huxley believed he was descended from the apes on his grandfather's side or his grandmother's side. Wilberforce was in fact a knowledgeable and sophisticated critic of Darwinism.) Charles Darwin indeed rejected God, or at least the Christian God--but not because his theory of evolution led him there. McGrath points out that Darwin lost his faith, rather, over the teaching, much stressed in Victorian evangelicalism, that the souls of unbelievers are eternally condemned to Hell.

Rather than an outgrowth of scientific discovery, atheism was a purely philosophic phenomenon launched by intellectuals mesmerized by science and what they believed to be scientific theory. Baron d'Holbach (1723-89) argued that the existence of the universe could--and should--be accounted for on strictly materialist grounds. The prolific Marquis de Sade championed the overthrow of religion as a precondition to absolute sexual, social, and political freedom. Sade's enthusiasm for libertine Godlessness found an echo in the French Revolution-besotted Romantic poets such as Shelley and, later in the century, Swinburne, who blamed the "pale Galilean" for casting a gray pall over Western culture and, specifically, for interfering with Swinburne's special sexual kink, having his buttocks flogged raw in brothels. Earlier, Ludwig Feuerbach had invoked d'Holbach's rigorous materialism in arguing that religious belief was a mere projection of human emotions and God a wishful human invention. Karl Marx adapted Feuerbach's theories and branded religion the "opium of the people," a comfort that enabled the masses to live with their oppressive social conditions until such time as revolution should sweep away both faith and the class system. It was but a step to Nietzsche's proclamation that God was dead (and we should make sure He stays that way), and to Freud's insistence that religion was an illusion to be replaced by scientifically grounded psychology.

Throughout most of the 20th century, Marx and Freud reigned supreme as the gods of modernity, to the point that the liberal mainline Christian churches committed "suicide" (McGrath's word) in terms of membership as they scrambled to accommodate their theologies to the idea that God no longer existed. In philosophy, fashionable existentialism and logical positivism deemed "God-talk" irrelevant. Eventually the idols came crashing down. Freud became thoroughly discredited as a scientist and physician, and one by one the vaunted Marxist societies were revealed to be not only economic disasters but vortexes of suffering and wholesale slaughter. Atheism had once been a "religion of the autonomous and rational human being," McGrath writes, possessed of a "powerful, self-confident, and aggressive worldview" that totalistically promised the understanding and hence the mastery of everything. What it delivered was totalistic, all right: the dreary uniformity of the Stalinist city and the Nazi concentration camp. It should not really be surprising, then, that atheism is now in retreat. McGrath nicely limns the visible decline in the intellectual stature of its propagandists: from Feuerbach to Madalyn Murray O'Hair, the foul-mouthed dysfunctional mother who led American Atheists in and out of courtrooms and press conferences until her murder by one of her underlings in 1995.

McGrath is an engaging, anecdote-loving writer with irenic sympathy for all his subjects, even the atheists, whose classic critique of Christianity as intolerant and corruption-prone he believes has spurred the churches to reform themselves in positive ways. I found him a shade too irenic. McGrath properly celebrates the passing of secular modernity but goes on to give too much credit to the postmodernist theorists who helped push modernity over the edge. He seems to forget that Jacques Derrida, Michel Foucault, and their epigones are also militant atheists, with all the intolerance and totalitarian tendencies of that breed, and that academic postmodernism rests upon a Marxist substrate as surely as did Stalinism.

Even more distressing is the scant attention that McGrath pays to the highly credentialed and supremely self-confident Richard Dawkinses of the world. Science and religion need not be in conflict, but it remains the case (as McGrath himself notes) that atheistic scientific materialism is the religion of a strong plurality, perhaps the majority, of the world's scientists. They want to be known not as atheists but as "brights," smarter than and superior to the rest of us. The claims of such scientists--that their own interests and desires as the unacknowledged legislators of the world should prevail without restraint--are currently being played out in the political debate over government funding for embryonic stem-cell research. I wish that McGrath had entertained the possibility that atheism, while undoubtedly in philosophical and demographic twilight, may yet be experiencing a new dawn: a terrifying new alliance with money and power, of a kind even Marx could not have foreseen.

Charlotte Allen, author of The Human Christ: The Search for the Historical Jesus, co-edits the InkWell weblog for the Independent Women's Forum.