Side Effects
by Adam Phillips
336pp, Hamish Hamilton, £25

Adam Phillips has had enormous success over the years with his urbane mixture of psychoanalysis, literary criticism and commentary on everyday life. You may have had reservations about these elegant disquisitions about flirtation and kissing and so on, and wondered quite how urgent or relevant they really are - but one good thing about Phillips is that he takes it all seriously without ever becoming too po-faced. As he puts it, winningly, here, psychoanalysis should be "a pleasure worth having rather than the terrible and absurd institutionalised seriousness it has become".

One of the more enjoyable things about his earlier books was the way that he flickered from case studies of his clients to close reading of his psychoanalytic precursors, so that the arguments had concrete touchstones. Sometimes his reported responses to those clients were not exactly convincing, but that didn't seem to matter: these were vivid moments - the little girl who dreamt of spiders as a way of funnelling her rage, the little boy who said that worries were farts that don't work. They came across like characters in fiction, and he also went to fiction in his work to make some of his most interesting points. So I was particularly intrigued by the promise held out by this book, that it would go on investigating the relationship between psychoanalysis and fiction.

It is in this investigation, however, that the book disappoints. I was puzzled by an essay tantalisingly called "Making the Case: Freud's Literary Engagements". This begins with the strangely obvious: "The literary engagements of psychoanalysts are legion," and ends with the strangely vague, "For psychoanalysts, at least, the literary represents something. This is what the psychoanalyst faces if she thinks of herself as a writer. Because in writing the psychoanalyst threatens to stray from something or other." Although in between Phillips covers quite interesting ground - such as that Freud was worried about getting too close to literature and too far from science, or that psychoanalysts tend to go to literature to confirm rather than challenge their thoughts - I felt frustrated by the way the essay, like others here, tended towards abstraction and lacked the concreteness of an energetic engagement either with literature or with everyday, observed life.

When Phillips examines literature head on he is similarly prone to oscillate between the obvious and the vague. I fell eagerly upon his discussion of Jane Austen's Pride and Prejudice, because I feel that she is a writer whose suggestive lacunae are very much suited to playful excavation. But Phillips first tells us something that nobody has to be told about Pride and Prejudice: "It is as if they have to understand something, to learn something about their first impressions of each other in order to get on," he says, and goes on stating this obvious point in different ways for a couple of pages. Then he drifts into a dismissal of this great writer, apparently scorning her lack of psychological realism: "We may be charmed but we are not fooled." I wasn't charmed by this judgment; does Phillips mean that we aren't convinced by Austen? And if so, don't we need more examination of what it is that stands in the way of us and her happy endings? Who is this "we" to whom Phillips refers so often, and so airily?

That is not to say that there are no memorable nuggets in this book of disconnected essays and reviews. I liked one short essay on the family very much. It's only three pages long, but it puts across some good observations about how family is basically about just two things - about having children and regulating sexual desire, and how the two aims of the family are at loggerheads: "In our erotic lives we abandon our children, and in our familial lives we abandon our desire." This makes the children "both the objects and the saboteurs of their parents' desire".

But the pleasure of this little essay was swamped, overall, by the lack of focus of some of the other chapters. Obviously, a writer like Phillips is going to wear a tangential, diffuse style like a badge of pride, and indeed he puts at the beginning of one of his essays this rebuking epigraph for the impatient reader: "Tyrants always want language and literature that is easily understood."

But there is also a tyrannical aspect to a writing style that insists on not being easily understood even when its insights are not that complicated. Although Phillips never says anything controversial, he always approaches his material as if it was about to go off like a bomb, approaching it tentatively, sidling up to it, and using a great deal of hesitant throat-clearing, as though the direct truth is almost too inflammatory to handle: "as if to say ... could be described ... one could say ... in a certain sense ... as it were ... it would be more exact to say ... so to speak". As the book went on, I started to find this stylistic quirk more and more irritating.

So I was intrigued when I got to the chapter called "Nuisance Value" in which Phillips quotes Richard Rorty saying that interesting philosophy is a "contest between an entrenched vocabulary which has become a nuisance and a half-formed new vocabulary which promises great things ..." Because Phillips's own work had now become for me, that "entrenched vocabulary which has become a nuisance", I wondered if this essay would enlighten me about why his style had started to grate. But it only ended up strengthening my feeling of impatience.

We travel through Rorty to Orwell and then to Winnicott to hear about different kinds of nuisances - irritating style as nuisance, beggars as nuisances, and of course children acting up - but these were never really brought together, they were simply connected by a series of tangents. And the ending then returned to the beginning without having moved on very much. "And yet nuisance, by definition, creates a resistant, if not actually hostile, environment, it invites the avoidance it fears. Perhaps being a nuisance is wanting to start again; or nuisance is the sign of something that wants to get started. After all, an old entrenched vocabulary can be a nuisance, but nuisance always speaks in an entrenched vocabulary." In this way Phillips seems to be suggesting that anything that feels like a nuisance is of value in laying the ground for something else to happen. And yet, there is also the possibility, so to speak, after all, that in other words, to put it more exactly - it is simply a nuisance.

· Natasha Walter's The New Feminism is published by Virago.