TRADITIONALLY, atheism and religion are seen as diametrically opposed, but in this dense, challenging, and erudite little book, former politics and philosophy professor John Gray makes the argument that, historically, many supposedly godless intellectuals have taken on what amounts to a religious fervor. This is a familiar charge when applied to the authors of Bolshevism, Maoism, and Nazism, but Gray also directs it at a wide range of other targets, including Enlightenment sages, scientists, “liberals,” Ayn Rand, John Stuart Mill, and such so-called New Atheists as Richard Dawkins and Sam Harris. His point is not just that these diverse philosophers can seem zealous, but that they are actually in repressed accord with central notions of Christian monotheism, especially the beliefs that there are absolute moral values, and that history has an arc that leads to “progress,” the triumph of good over evil, and—ultimately—the salvation of humanity.

Gray finds these notions wrongheaded and makes no bones about saying so, calling some of the views he disagrees with “fraudulent,” “bogus,” and “meaningless.” Mill himself once spoke of “the deep slumber of a decided opinion,” and the author is clearly on a wake-up mission. He argues that history has no meaning, and that the belief in progress is unsubstantiated. What he himself believes is not nearly as clear, but in the end, he rejects many historical forms of atheism in favor of the worldviews of such thinkers as George Santayana, Joseph Conrad, and the Russian-Jewish philosopher Lev Shestov, who wrote in favor of a stark, mysterious reality, which is not as believers or atheists might prefer it to be, but just is.

Whether the reader may agree with Gray or not, the book will almost certainly provoke worthwhile thought. Along the way he provides fascinating capsule portraits of a number of notable atheists, from Voltaire to Dostoyevsky to the Marquis de Sade. —GABRIEL COHEN