If, as Nietzsche proclaimed, God is kaput, then what? In a highly readable and immensely wide-ranging work of intellectual history, Peter Watson surveys and summarizes the various answers to this question that have been proposed during the past 125 years. “The Age of Atheists” is, in effect, an account of 20th-century philosophical and moral thought, focused, as its subtitle explains, on “how we have sought to live since the death of God.”

Bear that subtitle in mind because it might otherwise be easy to mistake the character of Watson’s book. This is neither a polemic about the horrors of traditional religion nor an apologia for a rationalistic, scientific attitude to our place in the universe. You can go back to the work of Christopher Hitchens, Richard Dawkins or S.T. Joshi for sustained arguments about the virtues of atheism. What interests Watson is the proposed alternatives to religion, those systems, aesthetic beliefs and modes of life that have taken, or might take, its place. He thus ranges from Marx and Freud and Max Weber through symbolism and surrealism; describes theosophy, Bloomsbury, phenomenology, Nazi ideology and existentialism; discusses self-improvement and Samuel Beckett, as well as sex, drugs and rock-and-roll.

Some contemporary thinkers have argued that the decline or disappearance of religious belief leads to a thinning of one’s inner life. In effect, the wholly secular are missing out; they lack — and here Watson paraphrases and quotes the philosopher Charles Taylor — “a sense of wholeness, fulfillment, fullness of meaning, a sense of something higher; they have an incompleteness . . . ‘a massive blindness’ to the fact that there is ‘some purpose in life beyond the utilitarian.’ ” After all, once basic needs are met, people desperately want their lives to have meaning. In the words of anthropologist Clifford Geertz, “The drive to make sense out of experience, to give it form and order, is evidently as real and pressing as the more familiar biological needs.”

Watson’s book concentrates on those brave souls “who, instead of waiting and wallowing in the cold, dark wastelands of a Godless world, have devoted their creative energies to devising ways to live on with self-reliance, invention, hope, wit and enthusiasm.” In effect, “The Age of Atheists” looks at the myriad approaches by which we might re-enchant our lives in the here and now.

To begin with, Watson implies that certain ethical principles are paramount. First of all, as Oliver Wendell Holmes declared, “There is no one way that life must be.” Like philosopher G.E. Moore and the Bloomsbury circle, one should beware of dogma, absolutes and anything that favors abstraction and ideology over living, breathing human beings. Philosopher John Dewey further contended that continual “growth itself is the only moral end,” that self- ­creation or self-realization should be our aim during our earthly existence. On our death beds, we want to look back on our lives and be reasonably content with what we have made of them. Till then, we should strive to charge our days with intensity.

“Intensity” is a word that recurs throughout this book, in sections devoted to George Bernard Shaw, Martin Heidegger, D.H. Lawrence and Albert Camus, as well as W.B. Yeats, that self-professed poet of “ecstatic affirmations,” and Abraham Maslow, the psychologist of “peak experiences.” Oddly enough, Watson doesn’t quote the most famous passage about living passionately during our short interval upon this earth. I mean Walter Pater’s conclusion to his book “The Renaissance”:

“A counted number of pulses only is given to us of a variegated, dramatic life. . . . How can we pass most swiftly from point to point, and be present always at the focus where the greatest number of vital forces unite in their purest energy?

“To burn always with this hard, gem-like flame, to maintain this ecstasy, is success in life.”

Pater is invariably associated with “art for art’s sake,” but, in a larger sense, creative work itself can imbue life with richness and an almost sacerdotal significance. Wallace Stevens declared that “Poetry/ Exceeding music must take the place/ Of empty heaven and its hymns.” Virginia Woolf, in her fiction and other writings, further argued for the appreciation of small, homey things, for the consolation of “minor daily miracles” and intimate moments of being.

Above all, people yearn for connection with others, for what Nietzsche called “self- ­realization within a community.” We need to honor our glad animal spirits, too. Dionysian art forms such as bebop, abstract expressionism and modern dance, as well as the countercultural visions of the 1960s, suggest modes of spontaneity and exuberance that can soothe the sometimes oppressive weight of rationality and consciousness. Just striving to bring about a world where rapture and freedom flourish can give us purpose and lead to that rarest and most satisfying of emotional experiences, what Bernard Shaw once called “Mozartian joy.”

One essential tool for successful living is humor, whether haughty existential scorn or that oddly comforting sense that the world is fundamentally absurd. “Why attack God?” said the composer Erik Satie. “He is as unhappy as we are. Since his son’s death he has no appetite for anything and barely nibbles at his food.” Nobody actually needs to study Sartre’s “Being and Nothingness” to grasp that existence gains meaning through deeds, not words. What we do, not what we say we believe, is what we are.

Throughout “The Age of Atheists,” Watson registers the widespread suspicion that modern industrialism and capitalist materialism have leached meaning from our lives, which is why so many pop-psych movements and New Age cults have turned against the machine age. Following the bloodbath we call the Great War, its survivors, Watson concludes, were left to face a world without values. That depleted world would subsequently contain genocide, the possibility of nuclear annihilation, the ongoing threat of terrorist attack.

So how should one live without God? There is, obviously, no single or clear-cut answer. But I think Bertrand Russell was right to point out that “when striving ceases so does life.” To dream of comfort and ease is simply to yearn for death. We belong to the species homo faber, put on this earth to make things, to get on with our work. And, if I may quote nominalist theology in this irreligious context, to those who do what lies within them, God will not deny grace. In the end, though, even the most fortunate among us must deal with what Freud called “everyday unhappiness.” That, it would seem, is the default human condition. As Rilke wrote: “Wer spricht von Siegen? Überstehen ist alles” — Who speaks of victory? Endurance is everything.

Peter Watson has produced what is, in every way, a big book, one that bears reading thoughtfully, with a pencil in hand. For anybody who has wondered about the meaning of life, and that pretty much covers everyone past the age of 12, discovering “The Age of Atheists” will be an enthralling and mind­expanding experience.

Dirda reviews books for The Washington Post every Thursday.


How We Have Sought to Live Since the Death of God

By Peter Watson

Simon & Schuster. 626 pp. $35