I sometimes find it hard to believe that Steven Pinker really believes what he believes; surely, I think, some occult agency in his mind is forcing his conscious intellect to accept premises and conclusions that it ought to reject as utterly fantastic. I suppose, though, that that is one’s normal reaction to ardent expressions of a faith one does not share; at its worst, it is just a reflex of supercilious fastidiousness, like feeling only an annoyed consternation at having to step over someone in the throes of mystical ecstasy in order to retrieve an umbrella from the closet. A healthier sentiment would be generous and patient curiosity, a desire to learn whether the believer has in fact”guided by a rare purity of heart”glimpsed truths to which one’s own cynicism or coarseness has blinded one.

Not, of course, that Pinker would care for that way of putting the matter. He detests religion and thinks of himself as a champion of something he blandly calls “reason” (that is the most enchantingly guileless aspect of his creed). In his latest book, The Better Angels of Our Nature: Why Violence Has Declined , he devotes over seven hundred pages to arguing the case that modernity, contrary to the common impression, has seen a steep decrease in every kind of violence”domestic, political, criminal, and martial”as a result of a variety of causes, but principally because of the triumph of “Enlightenment” ideas. It is a simple narrative, and at many points a painfully simplistic one, but it is clear and bracing and merits sympathetic consideration.

Whether Pinker himself does the tale justice, however, is debatable. He is definitely not an adept historian; his view of the past”particularly of the Middle Ages, which he tends to treat as a single historical, geographical, and cultural moment”is often not merely crude, but almost cartoonish (of course, he is a professed admirer of Norbert Elias). He even adduces two edited images from Das Mittelalterliche Hausbuch as illustrations of “the everyday texture of life in medieval Europe,” without noting that they come from a set of astrological allegories about planetary influences, from which he has chosen those for Saturn and Mars rather than, say, Venus and Jupiter. (Think what a collection of Saturnine or Martial pictures he might have gathered from more recent history.)

It is perfectly fair for Pinker to call attention to the many brutal features of much of medieval life, but one would have more confidence in his evenhandedness if he acknowledged at least a few of the moral goods that medieval society achieved despite its material privations. He says nothing of almshouses, free hospitals, municipal physicians, hospices, the decline of chattel slavery, the Pax Dei and Treuga Dei , and so on. Of the more admirable cultural, intellectual, legal, spiritual, scientific, and social movements of the High Middle Ages, he appears to know nothing. And his understanding of early modernity is little better. His vague remarks on the long-misnamed “Wars of Religion” are tantalizing intimations of a fairly large ignorance.

Perhaps such complaints miss the point, though. Pinker’s is a story not of continuous moral evolution, but of an irruptive redemptive event. It would not serve his purpose to admit that, in addition to the gradual development of the material conditions that led to modernity, there might also have been the persistent pressure of moral ideas and values that reached back to antique or medieval sources, or that there might have been occasional institutional adumbrations of modern “progress” in the Middle Ages, albeit in a religious guise.

He certainly would not want to grant that many of his own moral beliefs are inherited contingencies of a long cultural history rather than?discoveries recently made by the application of disinterested “reason.” For him, modern culture’s moral advances were born from the sudden and fortuitous advent of the “Age of Reason,” which”aided by the printing press”produced a “coherent philosophy” called “Enlightenment humanism,” distilled from the ideas of “Hobbes, Spinoza, Descartes, Locke, David Hume, Mary Astell, Kant, Beccaria, Smith, Mary Wollstonecraft, Madison, Jefferson, Hamilton and John Stuart Mill.” We know what he means: not the dark side of the “Enlightenment” and the printing press”“scientific racism,” state absolutism, Jacobinism, the rise of murderous ideologies, and so on”but the nice Enlightenment of “perpetual peace,” the “rights of man,” and so on.

Well, each to his or her own tribalism, I suppose. It is pleasant to believe one’s society is more “enlightened” or “rational” than all others, and Pinker has every right to try to prove the point. He would be more convincing, though, if only the central claim of his book were not so entirely dependent upon a statistical fiction.

That is to say, yes, of course modern societies have reduced certain kinds of brutality, cruelty, and injustice. Modern technology makes it far easier to control crime. We have weapons both too terrifying to use in open combat and so precise that we can kill at great distances, without great armies, out of sight and mind. We have succeeded at reforming our own nations internally in ways that make them ever more comfortable, less threatening, and more complacent. Our prison system is barbaric, but not overtly sadistic, and our more draconian laws rarely inconvenience the affluent among us. We have learned to exploit the labor and resources of poorer peoples not by enslaving them, but merely by making them “beneficiaries” of globalization. The violence we commit is more hygienic, subtler, and less inconvenient than that committed by our forebears.

Even so, the numbers do not add up. Pinker’s method for assessing the relative ferocity of different centuries is to calculate the total of violent deaths not as an absolute quantity, but as a percentage of global population. But statistical comparisons like that are notoriously vacuous. Population sample sizes can vary by billions, but a single life remains a static sum, so the smaller the sample the larger the percentage each life represents. Obviously, though, a remote Inuit village of one hundred souls where someone gets killed in a fistfight is not twice as violent as a nation of 200 million that exterminates one million of its citizens. And even where the orders of magnitude are not quite so divergent, comparison on a global scale is useless, especially since over the past century modern medicine has reduced infant mortality and radically extended life spans nearly everywhere (meaning, for one thing, there are now far more persons too young or too old to fight). So Pinker’s assertion that a person would be thirty-five times more likely to be murdered in the Middle Ages than now is empirically meaningless.

In the end, what Pinker calls a “decline of violence” in modernity actually has been, in real body counts, a continual and extravagant increase in violence that has been outstripped by an even more exorbitant demographic explosion. Well, not to put too fine a point on it: So what? What on earth can he truly imagine that tells us about “progress” or “Enlightenment””or about the past, the present, or the future? By all means, praise the modern world for what is good about it, but spare us the mythology.

And yet, oddly enough, I like Pinker’s book. On one level, perhaps, it is all terrific nonsense: historically superficial, philosophically platitudinous, occasionally threatening to degenerate into the dulcet bleating of a contented bourgeois. But there is also something exhilarating about this fideist who thinks he is a rationalist. Over the past few decades, so much of secularist discourse has been drearily clouded by irony, realist disenchantment, spiritual fatigue, self-lacerating sophistication: a postmodern sense of failure, an appetite for caustic cultural genealogies, a meek surrender of all “metanarrative” ambitions.

Pinker’s is an older, more buoyant, more hopeful commitment to the “Enlightenment””and I would not wake him from his dogmatic slumber for all the tea in China. In his book, one encounters the ecstatic innocence of a faith unsullied by prudent doubt. For me, it reaffirms the human spirit’s lunatic and heroic capacity to believe a beautiful falsehood, not only in excess of the facts, but in resolute defiance of them.

David Bentley Hart is an editor at large for First Things . His most recent book is The Devil and Pierre Gernet .