Awful charms of an imaginary Bedlam

The Dumb House by John Burnside, Cape, pounds 8.99; Roz Kaveney interprets a terrifying fable of western reason run amok

The whims of absolute power are as terrifying as its policies. Various legendary rulers investigated the origins of language by having children reared by mutes, presumably - though the legends never state as much - mutes forbidden to sign. We know, from children reared lovingly by animals or abusively by humans, that to fail to acquire language is to fail to acquire thought. There is some damage that cannot be undone.

The narrator of Burnside's terrifying little story is no stranger to damage. His vague father and self-dramatising mother keep him at home and desocialise him to the point where, once they are dead, no one else is real. The damage he does is a requital of subtler damages done to him.

He acquires an interest in language; it might have been anything, strictly speaking, and he would have found ways of turning the pursuit of know- ledge into the abuse of power. Language, though, is a novelist's business, and Burnside shows the perversion into monstrosity of his own natural curiosity. And Burnside's own reading in popular linguistics and cognitive studies is rehearsed at a length which never quite becomes tedious because it's represented as the symptom of a dangerous monomania.

The narrator's quest for knowledge leads him to a mother whom he repeatedly rapes when she is drunk, and a child whom he brutalises. The child is speechless, but not without a certain knowingness; the narrator breaks his fingers for dumb insolence, the first indication that the resistance of the powerless will has its price.

He pursues knowledge with the ferocity of the hobbyist and the autodidact. Burnside's intense cynicism about the rational is crude enough: it is in a branch library that the narrator catches sight of two of his victims. The vulnerable innocence of one, the almost mindless Lillian, is signalled by the fact that she goes to the library not to read, but to look at pictures.

The narrator is not, ever, in control. When he brutally murders Lillian's beggar boyfriend, it is through a misunderstanding. Lillian dies in childbirth under his inexpert care - there are some things you cannot just look up in a book. His experiment with the twin children she bears him is endlessly frustrated; he played them non-vocal music and they develop a private language of chant and singing. Even toddlers can frustrate him.

But of course he has more power than the twins. He severs their vocal chords and then, satisfied at having suppressed their singing, poisons them. He has got away with it, and will do it again. It is at this point that we realise most fully that what we have just been harrowed by is fable as much as novel. If the narrator is not intended to be the western rational mind in semi-allegorical action, he bears a more than passing resemblance to it.

This is a powerful addition to that sub-genre of fiction which consists of Theophrastian portraits of the dangerously mad: a sub-genre that includes, for example, Iain Banks's The Wasp Factory and John Lanchester's The Debt To Pleasure. To add moralising to the pleasures of the sub-genre is bad faith, though. Surely our pleasure in visiting such imaginary Bedlams is itself a symptom of the whimsical, all-powerful rationality that Burnside so much dislikes.