THIS slim volume of 121 aphorisms may come as a surprise to enthusiasts of Adam Phillips's previous work; On Kissing, Tickling and Being Bored and, more recently, On Flirtation, danced with the author's inquisitive mind and leaped with his uncanny ability to argue points with persuasive dexterity. Monogamy, however, is an entirely different type of fish. In it, there is none of the joyous yet strenuous and completely satisfying argument which has become Phillips's trademark. It does not dance; nor does it leap. Still, there are many fine salmon which elude the eye at river's edge and this small book is just that. It swims strong and well from the deep source of Phillips's intelligence, but it is not easily caught.

Monogamy (note the absence of the characteristic "On" in the title), says Phillips in his preface, "is an enquiry into the word we". At first blush, though, Phillips appears to be doing anything but enquiring; he posits, yes, and suggests and claims and even insists, but he does not explicitly enquire. Indeed, aphorisms by their very nature are inquiring only by the reflexive response they might provoke.

Loosely, monogamy is viewed by Phillips as an ideal which "makes the larger abstractions real, as religion once did", and he contrasts it "not with bigamy or polygamy but with infidelity, because it is our secular religion". Despite the ambiguous use of "it" in this instance (for it is unclear as to whether it refers to monogamy or to infidelity), Phillips gradually but tentatively emerges as a proponent of infidelity.

In aphorism 48, for example, Phillips refers to his pluralistic partners. In aphorism 56, he claims that, "Most infidelities aren't ugly. They just look as though they are". In 74, he insists that "there is nothing more terrorising than the possibility that nothing is hidden. There's nothing more scandalous than a happy marriage". And, in 121, the last aphorism, he posits: "Monogamy and infidelity: the difference between making a promise and being promising."

There are many memorable - aphorisms here and just as many which we have heard innumerable times before expressed in different ways. Phillips succeeds in his unusual turning of cliches, but it seems unlikely that someone with so fine an intelligence as his would swim the murky waters of monogamy equipped only with aphorisms without good reason. There is, there must be, some underlying current.

Phillips frequently seems overwhelmingly sceptical, even cynical, about monogamy. In aphorism 2, for example, he suggests that we are incapable of thinking clearly about monogamy because we take it for granted. Similarly, in No 42, he claims that "the problem with monogamy is that we have never found the words for it". One rather suspects that, had he the brass neck, he would have ended it in the same enigmatic way that Wittgenstein ends his Tractatus: "What we cannot speak about we must pass over in silence."

Deep waters are being fished here, it is true, but this reviewer believes that Monogamy cannot be fully appreciated unless it is viewed in the framework of his previous work, specifically "Karl Kraus's Complaint" in On Flirtation. There, he reviews both Edward Timms's book, Karl Kraus: Apocalyptic Satirist (1986), and Kraus's accomplishments and shortcomings. A contemporary of Wittgenstein's, Kraus was among other things a journalist and a satirist who displayed a scathing contempt for Viennese society in the early part of this century. And, like Phillips in Monogamy, he employed aphorisms to turn "empty phrases inside out" and tended to "stand disdainfully aloof from the nexus of human society".

In this essay, Phillips is profoundly sympathetic towards Kraus, but has his reservations about Timms's book. "Karl Kraus's Complaint" closes with Phillips's speculation that "Timnis' book will be indispensable when we have that most unlikely thing, an English Kraus". Perhaps, then (with the most delicious irony), Phillips is putting himself forward as "that most unlikely thing" with these 121 aphorisms on that elusive ideal that is monogamy.