The authors of both of these novels are sharp, confident, tolerant and civilised. They know their way around the American literary world (one is Arthur Miller's daughter, the other Paul Auster's wife) and they have earned their rightful place within it. They deal with big subjects: the unbidden ways in which the past intrudes into the present, the tug of earlier generations on those alive now, the unarguable fact of death, the stressful connections between New York and the wider United States. It should be enough to guarantee two fine novels, but in each case the last page is reached with a feeling of disappointment.

In Miller's book, Pippa Lee has moved to a retirement community with Herb, her elderly editor husband. She starts behaving strangely in her sleep and comes to realise that marriage (his third, her first) hasn't assuaged the troubles of her youth, only veiled them. As the narrative moves between first and third person, we meet Pippa's pill-popping mother, her lesbian aunt's lover who soon has her starring in porn films, her louche city friends, her conventional but unhappy neighbours, her twin children. There are affairs and suspected affairs, suicides and emotional tirades, intertwined with drunken dinner parties and curative encounters with nature.

Miller's experience as writer-director in the cinema shows in her skilful handling of a number of scenes. There's a fine moment when, in her teens, Pippa runs away through Manhattan to the East river, and stands in her thin coat watching “the boats go by, churning up water turned the colour of fire by the setting sun's reflection”. Her awkward daughter is recalled as a child giving an ice-cream to another girl, “angry at her own good fortune”. These striking episodes, however, are set within a less convincing and increasingly melodramatic narrative.

Pippa's concluding act is to drive towards “the clear distance” with a moneyless young man who is covered in a winged tattoo of Christ. Riding off into an untold story is an all-too conventional ending; it's no more plausible here than Pippa's teenage vision of a “feathered heavy” angel entering her bedroom. Earlier, she has hung out with “probably the finest fiction writer in the country” and a man who becomes “one of the highest-priced artists of his generation”. Even the cultural elite can sometimes be infected by the crass superlatives of Madison Avenue. Siri Hustvedt has written a mystery story that develops into a subtle and complex novel. Erik Davidsen, a New York psychoanalyst, tries to discover what lies behind a cryptic letter addressed to his recently deceased father. He is helped by his sister (the widow of a novelist) who is being harassed by a reporter with a nose for scandal. He is erotically obsessed by his new tenant, a young black artist - and she is stalked by her child's estranged father. The narrative moves across time to the Midwestern lives of Erik's Norwegian forebears and back to the present sufferings of his patients.

Hustvedt switches gracefully between her characters, involving them in each other's webs of grief and secrecy, confession and anger, lust and need. She weaves together family saga, comedy of manners and gothic horror, and seamlessly incorporates excerpts from her own father's memoirs, movingly evoking farm life during the Depression and the random violence of war. The book is concerned with the question of who owns the copyright in our sense of self - can it be found through art, therapy, memory or action? With great skill, she shows inner and outer worlds colliding with and penetrating one another.

Yet for all its factual ballast, the book feels more trivial than it should because, paradoxically, it strains so hard to be serious. The symbolism can become obtrusive; the tenant's embarrassingly cute daughter uses an entire ball of string to join Erik to his furniture because “that was my mission... to tie everything together”. Some sections seem to have been earnestly transcribed from a philosophical notebook; Descartes, Pascal, Kierkegaard and Wittgenstein all feature in a single paragraph. At one point, Hustvedt becomes a writer writing about a writer writing about a writer writing about a writer. Writers enjoy this; readers may be less enchanted.

The Private Lives of Pippa Lee by Rebecca Miller
Canongate £9.99 pp240
The Sorrows of an American by Siri Hustvedt
Sceptre £16.99 pp316

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