When the American poet Louise Glück was awarded the Nobel prize for literature in 2020, the Swedish Academy commended her “voice that with austere beauty makes individual existence universal”. They might have added that she makes the individual female experience universal, joining it to the canon of male mythology in ways even her titles make clear. The Seven Ages, from 2001 – a stunning reflection on human destiny – was preceded by both The Triumph of Achilles (1985) and Ararat (1990), for example, and followed by Averno (2005), named after the traditional site of the entrance to hell. While her earlier work explores family psychodrama, these books portray the emotional violence of mid-life. In 13 poetry collections and two volumes of essays, Glück’s emotional intelligence never surrenders to cosy consolation, yet the writing remains exquisitely beautiful. None of this has changed in her first published fiction. Marigold and Rose can be devoured in a single sitting, and that’s probably the best way to enter its tonal world, which is strangely hypnotic, in part because the mood never swings to violent intensity, and in part because of the orderly rhythms of Glück’s prose. Ten short chapters tell us – though not in exact chronological order – about the first year in the life of twin girls, the eponymous Marigold and Rose. During this period their grandmother dies, their mother experiments with going back to work, and they are “distracted, like all babies, by feelings of triumph. First crawling, then walking and climbing, then talking.” The book might sound limited or even, given its subject matter, twee. Being Glück, it is nothing of the sort. Instead, like her poetry, it gains its force from acute observation. In the final chapter, for example, as the protagonists attend a celebration for their first birthday, “Marigold … looked grimly out at the party from her high chair. Chaos and imprecision, she thought. Grown-ups were milling about … Meanwhile people they didn’t know were touching them and calling them lambs and chickens though it was perfectly obvious they were human babies. Aging human babies, Marigold thought.” Which is funny, in a wryly goth way. But humour isn’t this book’s endgame. Readers familiar with Glück’s writing will be reminded of the spare poetic diction she developed in her breakthrough second collection, The House on Marshland (1975), with its fine-drawn narratives of family life. As if to underline the resemblance to her verse, each chapter of Marigold and Rose is divided not into paragraphs running discursively from one to another, but into linked blocks of text separated by what elsewhere in her work we would call stanza breaks. And indeed these text blocks do work rather like the discrete stanzas of a poem. Each acts as a kind of choreographed freeze-frame within the story: juxtaposed, they resemble a frieze. This way of writing brilliantly evokes the timelessness of early childhood, and indeed of babyhood, before a child has even adapted to her own circadian rhythms. There is that sense of suspension, of living without past or future, which is the superpower of infancy: “Outside the playpen there were day and night. What did they add up to? Time was what they added up to … At the other end of time your official life began, which meant that it would one day end.” All this creates a subversive vision in which adults are imprisoned by time, and also by language. And it’s here the author is at her most transgressive, clothing the nuanced reactions of the babies in sophisticated language – even while acknowledging that they don’t have such words. Indeed, only Rose has learned to speak by the end of the book: “Since she had started talking, Rose felt she was turning into a tyrant. And Marigold was quieter than ever … studying the alphabet book for clues.” Readers wedded to realism may find this strategy irritating, but it’s a way to explore the prelinguistic life of an infant without reducing it to incoherence. And, after all, clothing the hidden inner lives of others with words is what all fiction does. We learn, piecemeal, that Marigold is the smaller, frailer twin, as well as the second-born, and that the pair started life in an incubator. There are reflections on unity and individuation: punningly, on their first birthday the monozygotic twins wonder how they can “turn one” when they already “had been, Marigold knew. Long ago, when they were an egg.” Rose is a gregarious extrovert, while “next to Marigold’s name there were a lot of needs improvement boxes checked”. But the book isn’t hung up on the occult nature of twinship. Instead, its identical twin girls feel more like a way to imagine two simultaneous versions of the (female) self. The twins observe each other’s vulnerabilities and triumphs with the protectiveness of allies. Rose worries about Marigold’s unworldliness. “And then, because she was like her name, steadfast and true, she united herself with her sister, as though they were a single story to which Mother and Father were just witnesses.” This novella offers a tender examination of alternative ways into girlhood, one of which is by way of being a writer. “Marigold was writing a book. That she couldn’t read was an impediment. Nevertheless, the book was forming in her head. The words would come later.” A portrait of the artist as infant twins? I think so. And for this consummate dive into the multiple possibilities of selfhood, we should be grateful. Fiona Sampson’s Starlight Wood: Walking back to the Romantic Countryside is published by Corsair. Marigold and Rose: A Fiction is published by Carcanet (£12.99). To support the Guardian and Observer, order your copy at guardianbookshop.com. 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