The Last Supper, By Rachel Cusk

A high-minded novelist tows her kids round Italy

There's something about Italy that brings out the best, and the worst, in novelists. DH Lawrence, EM Forster, Barry Unsworth, Matthew Kneale, Muriel Spark – and I need scarcely add, myself – have all succumbed to the delights and perils of its art and beauty. Now there is Rachel Cusk, whose first travel book comes in the wake of six prize-winning novels and one highly controversial, bestselling book, A Life's Work, on the exigencies of motherhood.

As in A Life's Work, her journey begins with deep disquiet. The universal philistinism of the inhabitants of Bristol, and a desire for change from the "endlessly repeating blankness" of domestic life, means their house is put on the market. Soon Cusk and her accommodating photographer husband, plus two small daughters, are on their way to France, then Italy, their spirits rising with the temperature in time-honoured fashion.

Faithfully, she records how her family upsets one host after another, sometimes commenting on them with ironic perspicacity and sometimes clearly oblivious to the effect she, her smoking and her persona is having on them. Both intentionally and unintentionally, The Last Supper is as funny as Diary of a Nobody. I admired not only her toughness (how on earth did she get her daughters, aged five and six, to go round so many Italian museums and enjoy "the discipline of art"?) but also the bold way that she interleaves her journey with observations on particular Italian artists, linking them to the over-arching theme of great art, and the tug between "duty and desire". Cusk's brilliance at describing landscape, the "art in daily things", Italian cuisine and a series of vicious games of tennis is part of what makes her worth reading, though she is equally interesting on painters such as Piero della Francesca, Cimabue and Raphael. It's not only particular painters she's trying to penetrate but art itself. What is the morality of art? How can it reconcile her to the mundane, the temporal, the ugly?

These are not stupid questions, unfashionable as they are. The battle against "fixity and predetermination", the struggle to record the instant of reality, and her antipathy to the Catholicism in which she was raised are all part of the same restless probing. She grits her teeth, in the knowledge that she may be setting our own on edge.

One is made to feel a variety of strong emotions when reading Cusk. Her reputed snootiness reached a crescendo a couple of years ago in a piece decrying the middle-brow tendencies of a local book group which she joined, and it's still in full flow here. Yet all her work radiates a fine intelligence and the writer's equivalent to an exquisite singing voice. The Last Supper is written with characteristic wit, courage, curiosity and, I'm afraid, condescension to lesser mortals. It is predictable that, like EM Forster's sensitive travellers, she despises the package tourists who crowd museums. Are they merely "a thick, hot cable of bodies", afraid of beauty, or are they "an overgrown humanity trying to fit into the narrow, beautiful past"? A third possibility – that they might be on a budget, or unable to take three months off to learn Italian, or are even more overwhelmed by their families than herself, never strikes her.

After A Life's Work, Cusk was judged and found wanting both as mother and writer by people unable to understand how, for a woman artist, these forms of creativity are particularly hard to reconcile. Here, though she mentions her daughters' innocent bewilderment at being uprooted first from Bristol and then from the Tuscan house where they spend some weeks, she portrays herself as tender and exemplary, singing every song from The Sound of Music, telling them the plots of Shakespeare plays and regularly baking bread. It is the fate of many outstanding young artists to come under assault at the start, but the way forward is not to become paranoid, defensive or craven. It is to find a different way of maintaining integrity with an individual vision, and to recognise, as she almost seems to do at the end when encountering a spooky doll-maker, that every artist has the choice: between increasing nuttiness and isolation or, as all the greatest have consistently done, by taking succour from kindred spirits and becoming less remote. Artists need to find out not only the truth about themselves, and art, but the imaginative sympathy that reveals how all human beings possess an inner life, and dignity. If The Last Supper is a farewell to more than the dream of Italy, and what it represents at its silliest, it is a significant step in a long journey.