In the past twenty or so years, a tone frankly contemptuous of faith has emerged. Illustration by John Cuneo

In Tom Stoppard’s 1970 play “Jumpers,” the philosopher hero broods unhappily on the inexorable rise of the atheist: “The tide is running his way, and it is a tide which has turned only once in human history. . . . There is presumably a calendar date—a moment—when the onus of proof passed from the atheist to the believer, when, quite suddenly, the noes had it.” Well, when was that date—when did the noes have it? In 1890? In 1918, after the Great War? In 1966, when Time shocked its readers with a cover that asked whether God was dead? For that matter, do the noes have it? In most of the world, the ayes seem to be doing just fine. Even in secularized Manhattan, the Christmas Eve midnight Mass is packed tight with parishioners, and the few who came for the music are given dirty looks as they sheepishly back out after the Vivaldi.

The most generous poll never seems to find more than thirty per cent of Americans saying they are “not religious or not very religious,” though the numbers get up to around fifty per cent in Europe. But something has altered in the course of a century or so. John Stuart Mill said in the early nineteenth century that he was the only youth he knew who was raised as a skeptic; by the end of his life, skeptics were all around him. Yet, though the nineteenth-century novel is roiled by doubt, there isn’t one in which the doubters quite dominate. Whatever change has occurred isn’t always well captured by counting hands. At a minimum, more people can say they don’t think there is a God, and suffer less for saying so, than has been the case since the fall of Rome. The noes have certainly captured some constituency, obtained some place. What, exactly, do they have?

There’s a case to be made that the change is more like pulses than like tides. If the nineteenth century ended with freethinkers in every front parlor, for most of the twentieth century the sound of atheism became more agonized and muted. Madalyn Murray O’Hair, the firebrand head of the American Atheists, had an occasional spot on Johnny Carson, but it was always in the last ten minutes of the show, the same spot that, ahem, Johnny gave to authors. (Billy Graham got on right after the monologue.) The glamour lay in faith. Nearly all the great modernist poets were believers: Auden and Eliot in Anglo-Christianity, Yeats in some self-crafted Hibernian voodoo. Wallace Stevens, whose great poem “Sunday Morning” is all about what to do when you don’t go to church, saw his atheism treated very discreetly, like Hart Crane’s homosexuality.

Only in the past twenty or so years did a tone frankly contemptuous of faith emerge. Centered on the evolutionary biologist Richard Dawkins, the New Atheists were polemicists, and, like all polemics, theirs were designed not to persuade but to stiffen the spines of their supporters and irritate the stomach linings of their enemies. Instead of being mushy and marginalized, atheism could proclaim its creed. But why did the nonbelievers suddenly want stiffer spines and clearer signals? Why, if the noes indeed had it, did they suddenly have to be so loud?

A history of modern atheism—what did Voltaire say to Diderot? what did Comte mean to Mill? who was Madalyn Murray O’Hair, anyway?—would be nice to have. The British popular historian Peter Watson’s “The Age of Atheists: How We Have Sought to Live Since the Death of God” (Simon & Schuster) could have been that book, but it isn’t. Beginning with Nietzsche’s 1882 pronouncement that the big guy had passed and man was now out on the “open sea” of uncertainty, the book is instead an omnium-gatherum of the life and work of every modern artist or philosopher who was unsettled or provoked by the possible nonexistence of God. Watson leads us on a breakneck trip through it all—Bloomsbury and Bernard Shaw, Dostoyevsky and German Expressionism, Sigmund Freud and Pablo Picasso. If it’s Chapter 3, this must be Vienna.

This makes sense of a kind, the nonexistence of God being an issue for modern people, and rising up everywhere. But reporting on every place you see it doesn’t help to see it more clearly. (On one page, we hear about Anna Clark, Tennessee Williams, Stefan George, James Joyce, Philip Roth, Henry James, Wilhelm Reich, Valentine de Saint-Point, Léger, Milan Kundera, Michel Foucault, Jacques Lacan, Jean-François Lyotard, H. G. Wells, Gerhart Hauptmann, Aldous Huxley, John Gray, Eugene Goodheart, Jonathan Lear, and, of course, Nietzsche.) Argos, the hundred-eyed watchman, might have had more sight than other giants, but he didn’t have sharper sight. Would Matisse really never have painted “The Red Studio”—which Watson takes as a paradigm of post-religious art, with the artist’s self-made space replacing divine nature—if Nietzsche hadn’t made that memorable P.R. statement about the Deity’s demise?

The problem is that godlessness as a felt condition is very different from atheism as an articulate movement. Watson doesn’t distinguish clearly, or at all, between the two, and so his book manages to feel at once breathless and long-winded—much too rushed in its parts and too diffuse as a whole. Even his chronology of ever-growing disbelief seems off. “Modern art is a celebration of the secular,” he states confidently, meaning Picasso and his like, and although he backtracks quickly, he can’t backtrack far enough, since so much of modern art—Kandinsky, Mondrian, Rothko—has been religious or mystical in nature.

Only in the last hundred or so pages does the real contention of the book appear. For Watson, we are divided not so much between believers and non- as between what might be called Super-Naturalists, who believe that a material account of existence is inadequate to our numinous-seeming experience, and Self-Makers, who are prepared to let the human mind take credit even for the most shimmering bits of life. His enduring sympathies lie with the unduly forgotten historian and novelist Theodore Roszak and with the philosopher Richard Rorty. Both are conciliatory Self-Makers, who sought to elevate experience over arguments and, dissatisfied with science, made of religious feeling its own religion. Watson regards phenomenology as “the most underrated movement of the twentieth century,” and finds in its emphasis on happy sensations, on the thisness of life, the happiest alternative to old-time religion. Atheism sanctifies less of the world but names more of it, he seems to say, and this is in itself enough. This seems to leave the door open for believers to engage in expanded “naming” of their own, which would turn mighty Jehovah into little Tinker Bell—if you say his name enough, he lives. Still, for Watson this is the right, positive, mystery-affirming, life-enhancing, and pragmatic-minded faith to end up within.

That really useful history of atheism would, presumably, try to distinguish between Watson’s subject, the late-arriving romantic agony of Nietzsche and his disciples—which responds to God’s absence the way fifth graders respond to the absence of the teacher: you mean now we can do anything?—and the older tradition of Enlightenment rationalism: the tradition that gave God a gold watch and told him the office was now so well ordered he wouldn’t be needed any longer. This more polite but, finally, more potent form of non-faith has played a larger role in politics than the no-more-teacher kind, if a lesser role in the arts. It’s the subject of “Imagine There’s No Heaven: How Atheism Helped Create the Modern World” (Palgrave), by the N.Y.U. journalism professor Mitchell Stephens.