Random House/National Gallery of Art

“I paint flowers so they will not die,” Frida Kahlo once said, speaking for many an artist driven to wrestle with mortality yet also escape the time-bound realm. In Ali Smith's dizzyingly ambitious new novel, How To Be Both, a 15th-century painter, Francescho del Cossa, is yanked through time and space to invisibly observe a grieving 16-year-old in contemporary England, a creative and pedantic soul named George who seems to be quietly imploding from loss. In the wrong hands, such a device could be twee at best, Lifetime movie-ish at worst. But Smith is endlessly artful, creating a work that feels infinite in its scope and intimate at the same time.

How the reader experiences the novel depends on chance: Half of the copies are printed so that George's story occupies the first section of the narrative, and the other batch starts with Francescho's violent journey back from death to a ghostlike state that’s assumed to be some sort of “purgatorium.” Regardless of the order, the book requires at least one-and-a-half readings to appreciate clues in either half that resonate only after having read the other. This is the sixth novel from the Scotland-born, Cambridge-based Smith, who’s played with structure and time before. In her 2001 novel, Hotel World (which, like How To Be Both, was shortlisted for the Man Booker prize), she explored the wages of grief through the prism of five characters, one of them a ghost. How To Be Both pushes the theme, and the formal invention, to new extremes.

The book's other trick, deftly revealed by Smith 20 or so pages into each half, is that both characters are in fact female. Francescho, whose artistic talents become obvious in early childhood, is grieving for her dead mother, wearing her too-big clothes and hiding in a trunk, when her father persuades her to dress as a boy so that she can be apprenticed to a painter. (The alternative is living out the rest of her days in a nunnery, painting religious scenes no one will ever see.) When first "shot back into being like an arrow" into a gallery where George is staring at one of her paintings, Francescho assumes that George, a slender figure in jeans, is male. But Georgia, her real name, is a bereft daughter, mourning a mother recently dead of an allergic reaction to antibiotics. George (the name she goes by throughout) betrays no awareness of the presence accompanying her, but she becomes fixated on Francescho’s work as a way of staying close to her mother, who took her to see the del Cossa frescoes she loved in Italy shortly before she died. (Francesco—no "h"—del Cossa was a real artist whose work hangs in Europe as well as Washington's National Gallery of Art, although there’s no argument outside of this book that he may have been female.)

The parallels between the two characters, and the possibility that Francescho is either some sort of guardian angel or a spirit who’s unconsciously been summoned, could seem contrived. But Smith’s deliberate obfuscation of what, exactly, is going on makes the novel feel less mawkish and more metaphysical. It’s like a mystery to be marveled at rather than solved. Her writing is crisp and elegant throughout, elevating Francescho’s anachronistic observances of 21st-century life from predictably comic to poetic. "Look boy," she tries to tell an unobservant George, "cheerful thing: spring flowers in a sort of bucket hanging off the top of a metal pole stuck in the side of the roadway." A nearby blackbird's beak is "a good Naples yellow," and around George's eyes is "the blackness of sadness (burnt peach stone smudged in the curve of the bone at both sides)." The iPad George uses to snap pictures and watch pornographic videos, meanwhile, is assumed to be "a holy votive tablet" through which she witnesses "frieze after frieze of lifelike scenes of carnal pleasure-house love enacted before our eyes."

Where Francescho is arrogant and bold and fearless, George is numb, occasionally caustic, and often tender, like a bruise under the skin. "How can it be that there's an advert on TV with dancing bananas unpeeling themselves in it and teabags doing a dance, and her mother will never see that advert?” she wonders as she sits in front of the screen. “How can the world be this vulgar?" George watches pornography, it becomes clear, not for enjoyment, but because she's haunted by one particular video of a dazed, very young girl and an older man. She promises herself that she will watch it each day "to remind herself not to forget the thing that happened to this person," as if by paying tribute to one neglected soul she can excise some of her own pain. Artistic tendencies emerge as she creates murals in her bedroom. The memory lingers of her trip with her mother to the Palazza Schifanoia: There she was struck by how the bright blue of the sky in one of the frescoes—del Cossa’s, of course—"gives you a breather from the things happening above and below it," and by how a figure strangling a duck is "an amazing way to show how ordinary cruelty really is."

Is Francescho's spirit sent to George by design, or is George imagining Francescho's story to make sense of her own life? There’s a chance that both—the titular both—may be true. Smith has said that the duality of the novel, in which stories run over and alongside each other, is inspired by frescoes, which often bear layers of drawings underneath what’s visible. Among the questions she sets out to explore: how to be both male and female, how to laugh while in pain, how to know who you are and be able to escape that identity, how the past lives on in the present. The book is also full of hints about walls as barriers and enablers: Francescho paints on walls, her father builds them, and George crafts them out of photographs she takes, with each image becoming a brick in the final construction. Perhaps, Smith seems to suggest, every circumstance or obstacle can be subverted and become its opposite at the same time.

George's therapist, the aptly named Mrs Rock, tells her that "the word mystery originally meant a closing, of the mouth or the eyes. It meant an agreement or understand that something would not be disclosed." In How To Be Both, Smith manages the rare feat of conjuring up opaqueness and clarity. There are mysteries and unanswered questions, but also hints that parallels and connections abound, that everything in the world is related. Eyes that look beyond mortal surfaces, Francescho says at one point, may discover enduring fragments of spirit in even the most ordinary objects:

It is a feeling thing, to be a painter of things: cause every thing, even an imagined or gone thing or creature or person has essence: paint a rose or a coin or a duck or a brick, and you'll feel it as sure as if a coin had had a mouth and told you what it was like to be a coin, as if a rose told you first-hand why petals are, their softness and wetness held in a pellicle of color thinner and more feeling than an eyelid, as if a duck told you about the combined wet and under dry of its feathers, a brick about the rough kiss of its skin.

As Francescho crafts worlds and characters and stories from the raw materials of paint and canvas, Smith does the same in her chosen medium. What matters, she seems to say, is not so much how and why her characters come together, but rather the enduring impression that each is able to imprint upon the other, and upon the reader.

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