I don't think Lewis was by any means a natural storyteller, and all of his fiction suffers to one degree or another from his shortcomings in this regard. Every time he sat down to write a story he was moving outside the sphere of his strongest writerly gifts.
What were those writerly gifts? Above all he was a brilliant satirist and parodist — abilities bolstered by his greatest more-generally-intellectual gift, a prodigious memory — and the master of a familiar, trust-inducing essayistic tone. (A tone that, by the way, he put to excellent use in his scholarly work, which is why The Allegory of Love and his OHEL book remain so exceptionally readable.) Now, his fiction sometimes benefits from these skills. For instance, consider the just-right pitch of this passage from The Lion, the Witch, and the Wardrobe —
I hope no one who reads this book has been quite as miserable as Susan and Lucy were that night; but if you have been – if you’ve been up all night and cried till you have no more tears left in you — you will know that there comes in the end a sort of quietness. You feel as if nothing was ever going to happen again.
— or the terrific parodies of administrative jargon in The Screwtape Letters and That Hideous Strength.
But in the basics of the kind of storytelling he liked best — creating vivid characters and keeping a lively plot moving along — Lewis struggled, and I think at times he knew it. Note how in That Hideous Strength he has to pause to tell us what we are supposed to believe about his two protagonists: “Jane was not perhaps a very original thinker”; “It must be remembered that in Mark’s mind hardly one rag of noble thought, either Christian or Pagan, had a secure lodging.” Apparently we might not have figured out those points without explicit direction.
Think also of the palpable creakiness, the lumbering joviality, of the whole Bacchus-and-Silenus passage in Prince Caspian; and the still more lumbering, and for CSL unusually mean-spirited and score-settling, assault on Experiment House at the end of The Silver Chair; and the endless explanatory talkiness, even long after the main plot points are settled, of Perelandra. (His dear friend Owen Barfield — one of the few people regularly to stand up to Lewis in dialectical situations — rightly commented that in writing fiction CSL was afflicted by an “expository demon.” To Lewis’s credit, he told this story on himself.)
There are far, far too many such passages in Lewis’s fiction. In my view, his only novel that’s free of these faults is The Horse and His Boy (and even then the allegorical treatment, near the end, of how God is present with us in our suffering is almost too much of a good thing). In my view, neither Lewis’s detractors nor his devoted fans have taken these limitations seriously enough. It’s a problem for his fans because they remain puzzled when other readers don’t like Lewis’s fiction as well as they do, and tend to attribute any dislike to some kind of spiritual dysfunction. It’s a problem for his detractors because they tend to attribute to malice or ethical narrowness what might just be lack of competence: maybe, as I suggested the other day, Lewis fell into The Problem of Susan not because he was anti-woman or anti-sex but because his desire to make a certain theological point was stronger than his storytelling common sense.
And yet, despite these flaws, all his novels possess a remarkable, but hard to define, vitality. I say “novels,” but in at least some of them, certainly each of the Ransom books, the vitality stems from the fact that they’re not novels at all. Lewis may not have realized it, but in those books — and even in some of the Narnia books, especially The Magician’s Nephew — he was writing Menippean satires.
What is a Menippean satire, you ask? Well, please see this definition from Northrop Frye’s Anatomy of Criticism:
The Menippean satire deals less with people as such than with mental attitudes. Pedants, bigots, cranks, parvenus, virtuosi, enthusiasts, rapacious and incompetent professional men of all kinds, are handled in terms of their occupational approach to life as distinct from their social behavior. The Menippean satire thus resembles the confession in its ability to handle abstract ideas and theories, and differs from the novel in its characterization, which is stylized rather than naturalistic, and presents people as mouthpieces of the ideas they represent. . . . The novelist sees evil and folly as social diseases, but the Menippean satirist sees them as diseases of the intellect.
See also Mikhail Bakhtin, in the revised version of Problems of Dostoevsky's Poetics:
In the menippea there appears for the first time what might be called moral-psychological experimentation: a representation of the unusual, abnormal moral and psychic states of man — insanity of all sorts (the theme of the maniac), split personality, unrestrained daydreaming, unusual dreams, passions bordering on madness, suicides, and so forth. These phenomena do not function narrowly in the menippea as mere themes, but have a formal generic significance. Dreams, daydreams, insanity destroy the epic and tragic wholeness of a person and his fate: the possibilities of another person and another life are revealed in him, he loses his finalized quality and ceases to mean only one thing; he ceases to coincide with himself. . . .
Characteristic of the menippea is a wide use of inserted genres . . . [and] its concern with current and topical issues. This is, in its own way, the ‘journalistic’ genre of antiquity, acutely echoing the ideological issues of the day.
Can you imagine a better description of the generic tendencies of That Hideous Strength than these two critics offer? And these traits are prominent in all of Lewis’s fiction, even the books for children. He tried to write novels, but his deep scholarly knowledge, his polemical temperament, and his marvelous abilities as a parodist and satirist led him to write Menippean satires instead. I think this goes a long way towards accounting for Tolkien’s distaste for Lewis’s fiction: he himself, a born storyteller if there ever was one, knew that on some level Lewis was faking it, was writing not so much stories as extremely clever imitations of stories, fantastically skillful mechanical models of stories. And given his narrow tastes he couldn’t abide what his friend was doing.
But if we realize the kinds of books Lewis was (willy-nilly) writing, then many of the faults — faults primarily according to the canons of novelistic narration — do not exactly disappear but slide into the background. Lewis then emerges as someone who was a successful writer of fiction after all; just not the kind of fiction that he tried to write and wanted to write.