There's a scene in David Mitchell's coming-of-age novel, Black Swan Green, which is easy to miss unless – like yours truly – you have spent much of your life fascinated with the work of Ursula K Le Guin.

Black Swan Green's 13-year-old protagonist, Jason, wanders into the home of a desiccated but still glamorous aristocrat of the old school who offers to tutor him in poetry. "Tell me," she asks, "Who are your teachers … what are the writers you revere most greatly?"

Instead of offering Proust or Rilke, Jason tosses out, "Isaac Asimov. Ursula Le Guin. John Wyndham." (Not exactly what she was looking for.)
"But have you read 'Madame Bovary'?" she shouts. "This is your culture, your inheritance, your skeleton! You are ignorant even of Kafka?"

I love this scene not only for the way it's drawn, but for what it tells us about its author. It illustrates a journey – from the disreputable world of SF and fantasy to what we still call "literary" work – taken by many readers, including me. More important, it expresses a crucial shift that's gone on among the writers born in the 1960s: the movement to claim pop culture – sci-fi, comic books, pulp detective novels – as an influence on par with Flaubert or, in the States, Fitzgerald.

Black Swan Green sits somewhere between novel and memoir, and It's easy to see how Asimov, Le Guin and Wyndham provided some templates for Cloud Atlas, my favourite British novel of the last few years, with such a range of voices and genres – seafaring yarn, thriller, post-apocalyptic tale, and so on – as to be almost frightening. (It can seem as if each section is taking one phase of Le Guin's complex career as a model, then another - but let's come back to her in a minute.)

Mitchell's writing patrols what Michael Chabon has called "the borderlands" between the settled metropolis of realism and genre's wild frontiers – along, it seems to me, with all the most vital writers of my generation. Besides Cloud Atlas, the masterpieces seem to me to be Chabon's The Amazing Adventures of Kavalier & Clay, Jonathan Lethem's Motherless Brooklyn, and perhaps the short stories of Kelly Link. And it seems no coincidence that each of these writers is a dedicated follower of Le Guin's: Chabon is partial to The Lathe of Heaven, Lethem to the story Those Who Walk Away From Omelas. Virtually every dedicated reader I know loves The Left Hand of Darkness and The Dispossessed.

In the case of Le Guin – whose latest novel, Lavinia, recently arrived in paperback, and who turns 80 this October – realism has always been something she approached with suspicion. As a kid, she read science fiction in pulps like Astounding and Amazing Stories, but put them aside as a teenager. Tolkien was an early and enduring influence she never abandoned. In college she studied Romance languages and literature, not the literature of her own language. "I didn't want to be told what to read in English," she explained when I visited her last summer in Oregon. Italo Calvino and Jorge Luis Borges, writing from traditions that saw "realism" as a complex question, swept her away.

Whatever direct impact Cromwell and the Puritans had on the British Isles, it was, I'll wager, more temporary than their effect on the US. The country Le Guin and I were born into was founded by Puritans, not by tragic Celts or misty Arthurian heroes, and it will take centuries more to get them entirely out of our system. Le Guin addresses this sensibility in her 1974 essay, Why Are Americans Afraid of Dragons? As she points out, "in the old, truly Puritan days, the only permitted reading was the Bible," and today, she writes, many Americans, especially men, "have learned to repress their imagination, to reject it as something childish or effeminate, unprofitable, and probably sinful".

Because fantasy – like comics, SF and other pulp fictions – often appeals to children, it's often written off as childish. As she writes near the end of her essay, "I believe that maturity is not an outgrowing, but a growing up: that an adult is not a dead child, but a child that survived … So I believe that we should trust our children."

And this generation of writers, now mostly in their 40s, can be viewed as Le Guin's children. They will only get deeper and deeper into the project she helped begin.