Levels of Life, By Julian Barnes

Like its author's heroes, this hybrid work of fact and fiction touches both heights and depths

Julian Barnes would appear to be the quintessence of O Lucky Man, but there are highs and lows in every life. Levels of Life reveals the rich geology of Barnes's soul and excavates the darkest emotional depths.

In his novel Arthur & George, Arthur's Mam acquires a lodger: the poet and scholar Bryan Charles Waller, a man "far too easy and charming with life itself, dammit". Barnes's early novels are a bit like this. Metroland and Before She Met Me, bristling with artistry and promise, gained him a call-up to the 1983 squad of Granta's Best of Young British Novelists. There he is in the team photo, centre back row, suavely resplendent, wearing a wryly subversive thin red tie, next to a butch Adam Mars-Jones, but far enough away from troublemakers Ian McEwan and Martin Amis - who seem to be discussing a bigger-league game plan.

As the 2013 youth team of British "Best ofs" prepares to take its position next month, it's interesting to note how many of the first intake have become household names, none more so than Barnes. After being short-listed three times, he won the Man Booker Prize in 2011 for The Sense of an Ending, a novel about memory, fallibility and history. Barnes has never been one to respect the cane-wielding authority of History - "the lies of the victors" (interestingly, "the lays of the victors" in Metroland), "the self-delusions of the defeated" or "a raw onion sandwich, it repeats, it burps" - but in The Sense of an Ending, History is given a magisterial bloody nose.

From the sharp-witted vitality of his schooldays, Tony Webster's "peaceable" life turns into a "short history of humiliation" as an entirely unforeseen narrative emerges from a small, reckless act. As his brilliant but suicidal friend Adrian Finn puts it: "history is that certainty produced at the point where the imperfections of memory meet the inadequacies of documentation". Tony is floored by the deceptions of memory, punch-drunk with grief and remorse, unloved, left with the dregs of "great unrest".

In Barnes's debut Metroland, narrator Christopher Lloyd's glass is overflowing with the uniqueness and aspiration of a priapic 16-year-old: "there were more meanings, more interpretations, a greater variety of available truths. Things contained more". His Paris jaunt is a journey to discover "a vivid, explosive, enriching self-knowledge". It is May 1968, and the Paris students are threatening to burn down the city, an event that shook the world, while Christopher is quietly losing his virginity to a French girl. Broader politics are of no interest to him, only Art and the "imaginative sympathy" of love, or as Barnes puts it in "Parenthesis" in A History of the World in 10 1/2 Chapters: "this tiny precise pleasure of the night".

In Arthur & George, Barnes's historical recreation of a miscarriage of justice and an unlikely relationship between two late 19th-century British gentlemen, Arthur's method of controlling narrative is to conceive the ending of a story first: "how can you make sense of the beginning unless you know the ending?" The Sense of an Ending is bleakly elegiac, almost cruelly final. Blood cannot flow backwards; time cannot be reversed unless it's a trick of nature like the Severn Bore, running upstream creating a temporal illusion.

With sudden new memories, however, fresh narratives emerge and perhaps the morbid winter of Tony's soul should be read in the context of Metroland's spring, and Christopher's resolute, conclusive happiness: "People say that happiness is boring. Not for me"; and "perhaps it really was all all right?" Or perhaps not. There are no easy answers; our certainties are merely whimsical, and all we can say about history is "something happened".

Our fluid, slippery, metamorphic state and life's potential for catastrophic breakdown are explored in Levels of Life, a synthesis of history, fiction and memoir. The book is a meditation on perspective, emotional and physical, and explores man's early attempts to escape gravity by ballooning at a time when flight was deemed a sin. The aeronaut was visiting God's space and attempting to colonise it, looking down at earth from a great height. Ballooning was enlightening, progressive, a "sudden superiority", and allowed us to "look at ourselves better, with increasing truth".

But, like memory, height can be dangerous. You can crash and burn. As with Arthur & George, Barnes is meticulous with historical detail, taking delight in unexpected connections with history's eccentric mysteries, and seamlessly creating vivid narratives which are fictional embellishments.

We witness Colonel Fred Burnaby, 17-stone "balloonatic", falling hopelessly in love with the French actress Sarah Bernhardt and being liberated by the weightlessness of love which confers the "uttermost freedom" in a "silent moral space". Love gives air, exaltation, uplift; we aspire to the heightened state and yet "when we soar we can also crash". Bernhardt finds this stiff, comically diffident Englishman faintly ridiculous and she cannot accept a proposal of marriage from someone emotionally heavier than air. Fred is ill-equipped to deal with his plunge into despair.

"Every love story is a potential grief story". It is the third and final section of this compact, precise and beautiful book that hits you in the solar plexus and leaves you gasping for air. "The Loss of Depth" is Barnes's account of losing Pat Kavanagh, his wife of 30 years: "the heart of my life; the life of my heart".

Grief is banal and yet unique, and pain beyond words can only be expressed metaphorically. In ballooning's infancy, a historian recounts the impact of a young man who had dropped to his death from a height of several hundred feet.

Barnes describes his loss in the same way, as a long falling, "conscious all the time", and landing "feet first in a rose bed with an impact that has driven you in up to the knees and whose shock has caused your internal organs to rupture and burst forth from your body". Memory fails as "grief reconfigures time, its length, its texture, its function".

Two people come together and the world is changed. When one of them is taken away what is lost is greater than the sum of what was there. Barnes mourns Pat "uncomplicatedly and absolutely", and misses her "in every action, and in every inaction".

It's an unrestrained, affecting piece of writing, raw and honest and more truthful for its dignity and artistry, every word resonant with its particular pitch. It defies objectivity. Anyone who has loved and suffered loss, or just suffered, should read this book, and re-read it, and re-read it.