The Great War between Lewis and Barfield was a prolonged, often face-to-face and written intellectual dispute that began when Barfield embraced Anthroposophy. Although Lewis met that turn with shock, disgust, and resentment, Barfield’s counterarguments permanently unsettled two foundations of Lewis’s thought: his assumption that modern ideas were superior simply because they were modern, and his attempt to ground truth and value in a universe known only through the senses. The dispute was not a personal quarrel, but it became one of the turning points of Lewis’s life, moving him away from materialist realism without making him an Anthroposophist.

The shock of Barfield’s conversion

Lewis’s resistance took shape against a background of competing intellectual authorities. As a boy, he had been troubled by the treatment of Pagan religion in his classical education: religious ideas in Virgil were presented as illusion, while Christianity was accepted as the lone true exception without an explanation of why it deserved different treatment. Later, his materialist outlook began to waver when W. B. Yeats’s prose disclosed a serious belief in magic, and when Maurice Maeterlinck introduced him to Spiritualism, Theosophy, and Pantheism. Lewis did not assent to these beliefs, but their presence in the work of writers he regarded as responsible authorities introduced a disturbing possibility: there might be something beyond the material world, without that possibility necessarily belonging to Christian theology.

That earlier attraction made the news about Barfield especially difficult. As Lewis and Barfield’s generation of returned soldiers began to pass, Oxford filled with new faces and the question of a career grew more pressing. Then A. C. Harwood, followed by Barfield, embraced Rudolf Steiner’s doctrines and became Anthroposophists. Lewis felt that ideas he had tried to expel from his own life had reappeared in his closest friends. He thought Harwood too immovable to be susceptible and regarded Barfield’s free-thinking upbringing as protection against what he considered superstition. Barfield, Lewis noted, had encountered Christianity at school through a dictated list of Parables Peculiar to St. Matthew.

Lewis’s first response was not a careful appraisal of Anthroposophy but a fearful recognition of its familiar territory. He associated it with gods, spirits, afterlife, pre-existence, initiates, occult knowledge, and meditation—the very interests he had once found exciting and then tried to exclude. His reaction exposed how much he still relied on chronological snobbery: he used the word medieval as a term of abuse and regarded the spiritual as a dark departure from the modern outlook he called the New Look. He assumed his friends were driven by the same appetite for occult thrills that might once have drawn him in. In later reflection, he acknowledged that the evidence had been against this assumption. He saw Anthroposophy as difficult and, to him, reassuringly Germanic in its dullness, not a system catering to seekers of excitement; he also observed that it had not damaged the character of its adherents and had, in one instance, improved it.

An argument without a quarrel

Lewis later described his initial judgments as hard, unjust, and bitter, and offered his account partly as belated amends to his friends. Barfield’s conversion began what Lewis called the Great War between them, but he distinguished it from a quarrel. The dispute could have become personal, he wrote, had Barfield answered with anything like the violence Lewis allowed himself. Instead, the conflict took the form of almost incessant disputation, conducted both by letter and face to face, and continued for years. Its persistence mattered: this was not one decisive exchange but a sustained test of the assumptions through which Lewis interpreted belief and knowledge.

The first lasting result was Barfield’s attack on chronological snobbery. Lewis defined this as accepting the intellectual climate of one’s own age without examination and treating an idea as discredited simply because it had gone out of date. Barfield’s challenge required a different question: had the older position actually been refuted, and, if so, by whom and how conclusively? If it had merely fallen out of fashion, its disappearance proved nothing about its truth or falsity. That test also turned back on the present. The modern age, Lewis came to see, was itself a historical period, with characteristic illusions most likely to persist in assumptions so widespread that people neither thought to defend them nor dared to question them.

The crisis of realism

Barfield’s second major counterattack concerned the theory of knowledge implicit in Lewis’s earlier materialism. Lewis and Barfield had been realists in the technical sense: they treated the universe disclosed by the senses as the ultimate reality. Yet they continued to claim that disciplined abstract thought could yield indisputable truth, that moral judgment was valid, and that aesthetic experience was valuable rather than merely pleasing. Lewis recognized that these claims sat uneasily beside a worldview that made consciousness a subjective by-product of a fundamentally sensory universe.

The difficulty was not only theoretical. If Lewis kept the sensory universe as the sole reality, he would have to accept a more thoroughgoing account in which logic, ethics, and aesthetics were explained through behavior. He found that alternative literally impossible to believe, not merely unattractive or improbable. Barfield’s argument therefore compelled him to give up realism, a position he had defended since he began reading philosophy. Lewis admitted that his resistance had partly been cussedness: Idealism was dominant at Oxford, and he was inclined to oppose the prevailing school. Realism had also met an emotional need. He wanted Nature to exist independently of observation, indifferent and self-sustaining, and valued the encounter with sheer external fact that he associated with A. K. Hamilton Jenkin.

Once that position could no longer stand, Lewis felt driven toward a universe that was ultimately mental: mind could not be a late-arriving by-product, and logic had to participate in a cosmic Logos. He remained, at this stage, able to distinguish that conclusion from Theism. He saw the Absolute of English Idealist philosophy as a way of speaking religiously about an ultimate reality while keeping it impersonal, remote, and incapable of making claims on him. Such a quasi-religion offered a sense of transcendent reconciliation but, as Lewis later recognized, required no obedience. Its Heaven existed beyond the reach of human beings, who remained appearances rather than inhabitants of that reality. Lewis nevertheless valued having passed through this outlook and retained its central maxim: “It is more important that Heaven should exist than that any of us should reach it.”

A turning point, not a conversion to Anthroposophy

The result of the Great War was a change in Lewis’s intellectual ground, not his acceptance of Barfield’s Anthroposophy. Barfield never made him an Anthroposophist; he did, however, destroy the confidence with which Lewis had treated the modern intellectual climate as self-validating and the sensory universe as a sufficient basis for knowledge. The distinction is essential to the dispute’s outcome: Lewis could reject his friend’s particular doctrine while accepting that his own previous framework was inconsistent.

Lewis connected the change to other steps in his developing thought. He credited Henri Bergson with showing him necessary existence and said that Idealism brought him nearer to understanding the words of Christian thanksgiving for divine glory. The Norse gods had first suggested that glory to him, though he had not believed in them; he did believe, as far as one could believe in an unreal thing, in the Absolute. In retrospect, Lewis cast this intellectual movement as an unseen advance whose destination he did not yet understand. The conflict with Barfield thus prepared a wider reconsideration of religion: Lewis later described Pagan myth not simply as falsehood opposed to Christianity, but as a possible preparation whose hints might find their maturity elsewhere. The long argument did not settle every question, but it broke the intellectual barriers that had made such a reconsideration impossible.

The event’s significance

The Great War joined friendship to sustained disagreement without collapsing into estrangement. Its significance lies in the way Barfield’s challenge worked through Lewis’s own standards of evidence: it made him ask whether an old belief had truly been disproved, and whether his confidence in reason, moral judgment, and aesthetic value could survive his materialist account of reality. The answers did not immediately yield Christian belief. They did make Lewis less certain that modern materialism could explain what he continued to regard as real, and they left him more open to the religious history he had once dismissed.

In Lewis’s retrospective narrative, the dispute is a hinge between two forms of resistance: first, the dismissal of spiritual claims as obsolete or irrational; then, the recognition that the supposedly neutral modern position had its own period-bound assumptions and unresolved commitments. Barfield’s role was not to supply Lewis with a finished creed but to make his former intellectual shelter untenable. That is why Lewis remembered their years of argument as a turning point rather than a victory over his friend’s beliefs.