In assessing Lewis’s significance as a Christian apologist, the key is chronology. He is, of course. best known for his writings of the ’40s, and it is as the author of such celebrated books as Mere Christianity, The Pilgrim’s Regress, Surprised by Joy, The Problem of Pain, and Miracles that he is revered by many readers. But these early books are neither the whole nor even the most important part of the story. There is another more disconcerting side to the C.S. Lewis phenomenon—namely, the dark legacy of his later years. If we ignore or minimize it, we will be left with a very one-sided and highly misleading picture of Lewis and end up valuing him for the wrong reasons.

There is, of course, no denying the fact that, so far as the prospect for Christian apologetics is concerned, the Lewis of the ’40s is a far more encouraging figure. In these early books he fairly leaps from the page as the 20th century’s foremost defender of the faith, “the Apostle to the Skeptics” confronting his unbelieving or lukewarm contemporaries with the “case for Christianity.” Seldom has an apologist succeeded so completely in conveying the impression that Reason is on the side of Faith and that it is not the believer but the unbeliever for whom philosophical discussion poses problems. No issue is too difficult for him, no opponent too formidable. His effortless brilliance and confident finality irresistibly suggest that it is the intellectuals who have made simple things difficult and that it is high time to call a halt to these proceedings. If the real theologians had done their job, “there would have been no place for me,” he ruefully observes. But they have not and so there is. He will make things simple again.

Everything is eminently sensible and straightforward. He is “not asking anyone to accept Christianity if his best reasoning tells him that the weight of the evidence is against it.” But surely it is not, and if we are willing to think clearly and hard, we can establish a great deal “on our own steam.” Not only does he offer us “overwhelmingly probable” arguments for the existence of an infinite Object of desire, a Power behind the Moral Law, and a cosmic Mind; he is equally prepared to take on all comers, dispose of their objections, and put the embarrassed opposition to flight. He has heard it all before. Opposing positions are not only false but ludicrous, and crumble like sandcastles at the slightest nudge: atheism is “too simple,” naturalism is “self-contradictory,” and materialism is “a philosophy for the nursery” to say nothing of ethical relativism, which reduces moral judgments to “mere subjective preference” like a “fondness for pancakes or a dislike for spam,” or theological liberalism, whose denial that Jesus was God logically commits its exponents to saying that he was a lunatic “on the same level with the man who says he is a poached egg.”

Clearly this is the stuff of which legends are made. At first glance, it is a dazzling performance by a philosophical virtuoso at the height of his powers.

But a closer look dispels this initial impression. Lewis’s defense of Christianity relies heavily on three major proofs for the existence of God: the Argument from Desire, the Moral Argument, and the Argument from Reason. He never claimed that these arguments were original and, of course, they are not. They are, in fact, highly-compressed and simplified reformulations of technical philosophical arguments. And they are seriously flawed. Since it is on these arguments that his case for Christianity depends, the case fails.

There are other problems. Lewis’s arguments against opposing positions are often based on serious misunderstandings. Surely the inductive method of science is not based on the principle that “if you make the same guess often enough, it ceases to be a guess and becomes a Scientific Fact.” Nor are anthropologists usefully defined as debunkers of morality who try to undermine traditional values by travelling to “backward villages” in order to collect the “odd stories” that “country people” tell. Similarly, ethical subjectivists do not regard moral judgments as expressive of mere subjective preference, naturalists do not reduce human reasoning to an involuntary response “like a hiccup, yawn, or vomit,” and theological liberals are not logically compelled to say that Jesus was a lunatic. In short, Lewis’s favorite polemical targets are often little more than straw men.

Some will, of course, dispute these contentions. But if we view Lewis’s writings in chronological perspective, such protests are beside the point. Whatever we may think of his arguments and polemical tactics, the fact remains that Lewis himself came to have serious doubts about many of them.

It is precisely here that his later work provides an indispensable corrective. In both content and tone, these writings bear permanent witness to the remarkable change that had come over him. The buoyant confidence had gradually given way, first, to a subdued tentativeness and, toward the end, agonizingly exploratory groping. By his twilight years the transformation was so complete that he is all but unrecognizable—hardly the sort of writer to be hailed as “the Apostle to the Skeptics.”

What had happened? Idle psychological speculation aside, two contributing factors can be cited: one with reasonable certainty; the other incontrovertibly.

First, over the years Lewis had more than his share of critics. Although many of them can be summarily dismissed, others are not so easily disposed of, and a handful had a lasting impact. Of these one warrants specific mention—the British philosopher G.E.M. Anscombe who in 1948 read a paper to the Oxford Socratic Club in which she launched a devastating critique on Lewis’s recently published Miracles, subjecting his argument against naturalism to powerful criticism and demonstrating that his alleged proof for theism was fallacious. Lewis responded and an exchange followed. Although hardcore loyalists disagree, the unanimous consensus of those actually present was that Anscombe had won hands down, and that “a conclusive blow” had been dealt to one of Lewis’s most fundamental arguments. Lewis reportedly concurred, and was not only “deeply disturbed,” “miserable,” and “in very low spirits” after the encounter but continued to describe it “with real horror.” One biographer, in fact, claims that this bitter experience marked a turning point in Lewis’s career after which he had “learnt his lesson” and published no more books on the subject of Christian apologetics.

The second way of accounting for Lewis’s dramatic change of heart involves such intimately personal matters that they can only be discussed with a certain reticence. Had not Lewis immortalized them in one of his last books, they could not with propriety be discussed at all.

With his apologetic books behind him, Lewis’s subsequent writings on religion took on a different character. The ambitious scope and extrovert manner of the old days is replaced by a noticeably smaller-scaled and more piecemeal approach together with a correspondingly quieter tone and tree-ripened meditativeness. If there was any single problem that preoccupied (and finally haunted) him, it was the problem of contrary evidence—evidence that casts doubt on Christianity and calls Christian belief into question. And if there was any single event that unleashed this problem in its full fury, it was the death of his wife.

Lewis’s worries about contrary evidence were already apparent in his 1955 essay “On Obstinacy in Belief.” Although he had tackled this problem in The Problem of Pain, the arguments and assurances of that book are conspicuously absent. So is the earlier strategy of Mere Christianity in which religious doubts were traced to “mere moods” and religious doubters banished to the ranks of those who “dither to and fro” with their beliefs dependent “on the weather and the state of [their] digestion.” Here Lewis is no longer amused but uncommonly sober, on the defensive, and willing to make unheard-of concessions. It is no longer atheism but his own previous position that is “too simple.” The honest inquirer must now candidly acknowledge that the evidence for theism is, at best, “mixed” and that considerable ingenuity is required if the believer’s position is even to be “rendered tolerable.” The “philosophies for the nursery” have proved to be more troublesome and resilient than anyone would have ever guessed and, in waging his polemical warfare against them, the apologist must employ heavier artillery than in bygone years. Throughout the essay, it is noteworthy how far Lewis has retreated and how meagerly his apologetic arsenal is now stocked.

But the worst was yet to come. A few years later Lewis was plunged into sorrow and overtaken by religious doubts of such paralyzing magnitude that he experienced a crisis of faith. Although he recovered, he was never the same again.

In 1956 at the age of 58, Lewis married Joy Davidman. It had been clear from the beginning that she was suffering from bone cancer and that her days were apparently numbered, but their hopes had been revived by an unprecedented event that Lewis described as the closest thing to a miracle that he had ever seen. His wife’s condition began to improve. She progressed from being bedridden to being able to get around in a wheelchair to walking with a cane. And the person who had taken the X-rays marvelled that her bones were as solid as rock. Lewis’s touching expression of his heartfelt gratitude can be found in “The Efficacy of Prayer.” A holiday to Greece was arranged, one of her lifelong dreams and a trip that provided Lewis with “the last great days of perfect happiness.” The essay on the efficacy of prayer appeared in 1959. Less than a year later Joy Davidman Lewis was dead—a victim of the very cancer they thought had been miraculously cured. And Lewis’s faith came crashing down “like a house of cards.” As a “safety valve against total collapse,” he wrote A Grief Observed.

There is no case for Christianity in this book. Gone are the persuasive arguments, the apt analogies, the sustaining consolations. Gone, too, is the already ebbing confidence of the essay on obstinacy. The apologetic arsenal is now empty and the apologist himself has been stripped naked. What remains is only a lonely and grief-stricken widower jotting down his thoughts and second thoughts in occasional notebooks.

A Grief Observed is an unflinching book, a book of many moods, the case history of a bereavement. No one—whether friend or foe—has penetrated to the bedrock Lewis who ignores or trivializes its disturbing revelations. First of all, there is undisguised grief in this book. Lewis had no patience with “pious jaw” about God’s way being the best way, and he recoiled from “all that stuff” about reunions on that other shore. His wife had died and he mourned for her. But there are also doubt and rage in this book. Seldom has a religious writer assumed such freedom in refusing to pull punches. Others have undergone similar experiences, but few have been bold enough to contradict Psalm 91, as Lewis did when he bitterly demanded to know why God is so very absent in time of trouble. This little book is a remarkable document in which a morally outraged believer storms the heavens for an answer to the problem of suffering.

But there is something else in this book—the loss, if not of faith, then at least of a belief in faith’s intelligibility. Lewis did not cease to believe in God, but he found it very hard to believe that God is good. What disquieted him most of all was not just his wife’s death, but the circumstances that had preceded it: the false hopes, the “miraculous” cure, the sense of having been toyed with. Unlike the evils discussed in The Problem of Pain, those which had brought his faith down like a house of cards were of a kind in which God seemed directly implicated: trickery, deceit, even cruelty.

Throughout his apologetic writings Lewis had insisted that God’s goodness must be understood in terms of our ordinary moral standards. God must be regarded as good “in our sense,” for only then will it be a goodness that we can recognize. Christianity does not require us to reverse our moral standards and resign ourselves to the fact that our “black” may be God’s “white.” Yet when in his hour of need Lewis applied these same moral standards to God, he found him wanting. Thus the Apostle to the Skeptics became a skeptic himself—if not about God’s existence, at least about his nature.

In the end, Lewis extricated himself from this skepticism. Having registered his protest against God, another possibility occurred to him. Perhaps his faith had been imaginary all along. If so, God could not allow him to labor under the delusion that it was true faith. He had to knock Lewis’s house down in order to bring about this terrible but necessary realization. So God is good after all.

This, of course, is no solution. To exchange one view for another simply because it enables you to retain a belief that you want desperately to retain is a sure indication that rationality has been sidestepped. Lewis did not show us that God is good in spite of appearances to the contrary and then conclude that his faith had been imaginary. He did exactly the opposite. He assumed that his faith had been imaginary and then concluded that God is good for having driven this point home. That is not an argument but a case of special pleading. At the same time, it is not hard to understand why Lewis grasped at this unlikely straw. Any other assessment would have required him to say that his faith had been real but unfounded—that the God he had believed to be good is really evil. The later Lewis had lost not only his wife, but with her, his composure and the will to argue. Our last glimpse of him is that of a man determined to believe in spite of himself and whose commitment to divine goodness had outrun his comprehension of it. By this time there were no longer battles to be won but promises to be claimed and hopes to be kept alive like the precariously flickering embers of a dying fire. Lewis claimed that his faith somehow survived. I am sure that it did. But it no longer invited the assent of the rational man.

I am touched by C.S. Lewis in his twilight years. Chad Walsh reports that when he visited Lewis for the last time, he found him “subdued and at loose ends.” The apologist who had launched his career by declaring that he was not asking anyone to accept Christianity if his best reasoning tells him that the weight of the evidence is against it finally arrived at precisely this impasse. And in order to move beyond it, he felt compelled to confess publicly that his faith had been imaginary.

A Grief Observed reveals many things about Lewis but none more important than that he was ultimately undone by the problem of contrary evidence and left with a deity of dubious moral character. After reading it, we can no longer read Lewis’s earlier books as we once read them. We now know that he came to have grave doubts about many of the views that he had so confidently and joyously defended in them—doubts out of which he could not find his way. This fact casts an eerie retrospective light over his entire career as an apologist.

Although there have been Christian apologists of far greater philosophical stature than Lewis, I know of no apologist of any age who struggled with the difficulties involved in Christian belief in so grippingly visible a way and at such personal cost. Read Lewis’s books desultorily and you will readily discover why his critics find them so facile and cavalier. But read them chronologically and attentively, and you will also understand why they continue to attract so vast an audience. A mentality is at work in these books that is more than the sum of its often troublesome parts. Yet toward the end it becomes a divided mentality, a mentality at odds with itself. The later Lewis had felt the full impact of religious doubt and although he could not abandon his faith, neither could he claim a greater certainty than he had attained. His perplexities remained, and he acknowledged them with a degree of intellectual integrity that is as remarkable as it is rare. The Lewis of the ’60s is no longer the Apostle to the Skeptics, acutely surveying the present state of the evidence, but the Reminder to the Forgetful, humbly searching for just enough light to face the day that lies ahead. Yet this is the Lewis of greatest personal stature, the Lewis who survives the collapse of his own arguments, and the Lewis who remains worthy of our highest and unqualified respect.

Dr. John Beversluis is a professor of philosophy at Butler University. He has recently written C.S. Lewis and the Search for Rational Religion published by Eerdmans. This article treats some of the themes developed in more detail in that volume