CARPENTER'S GOTHIC. By William Gaddis. Viking/Elisabeth Sifton. 262 pp. $16.95.

IT'S EXACTLY 30 years ago that William Gaddis published his vast and remarkable novel about fiction and forgery, The Recognitions. It showed a world of dark and complex plots where the faked and the forged seemed the basic conditions of human existence. To a number of critics, including myself, it was the starting place for a whole new direction in contemporary American fictional experiment, opening the path for Thomas Pynchon and the modern labyrinthine novel. We waited for Gaddis' second novel; but over 20 years were to pass before he came out with JR, another extraordinary book, about a sixth-grader who masters and manipulates the plots and systems of conglomerate capitalism.

The critics tried to find the right words for Gaddis' special qualities. This was the "cybernetic" novel, committed to the styles and techniques that could capture the noise and the redundancy of a technetronic age. His style, like Pynchon's, was the "paranoid" style, a way of writing of a world so made of plots and conspiracies that the individual is swamped by external systems and discourses. The terms are useful in catching at Gaddis' complex and baroque method, though they hardly suggest one of his strongest qualities: his enormous satiric vitality. What is clear is that Gaddis is one of the great talents of the recent American novel, though his books remain still something of a cult item. Happily they are now being reissued in Penguin paperback, to coincide with the appearance of his third novel in 30 years, Carpenter's Gothic.

At a mere 262 pages, Gaddis' new book is, in his terms, hardly more than a novella, lacking the overwhelming mass of the two earlier novels. But it shows no lack of his striking and baroque technique, or his talent for constructing labyrinthine plots and vast conspiracies. The direct action of the story is held over a few days in and around one single rented house up on the Hudson. Here lives Liz, the book's passive "heroine" and still center, the heiress to a corporation fortune which is still in litigation. Here comes and goes her husband Paul, an opportunist media consultant who is wheeling and dealing in the world of international corporations, law, Washington politics and fundamentalist religion. Here too, in a locked room, are the papers of the owner of the house, the geologist McCandless. Liz, damaged after a plane crash, consoles herself with Gothic fantasies, especially images from Orson Welles' film of the finest of Gothic novels, Jane Eyre. But meanwhile the world enters, endlessly, through the telephone's ceaseless ringing, the mailbox, the newspaper headlines (TEARFUL MOM), TV and the unstoppable, incomprehensible penetration of the corrupt political, commercial and religious practices of hyped-up, born-again America.

The house, appropriately, is built in carpenter's Gothic, the American domestic style based on the European Gothic forms, but using the skills and materials locally to hand. "All they had were the simple dependable old materials, the wood and their hammers and saws and their own clumsy ingenuity bringing those grandiose visions the masters had left down to a human scale with their own little inventions . . . a patchwork of conceits, borrowings, deceptions," recalls McCandless, returning to his house. These houses were built from the outside and the inside rooms filled in later -- an unmistakable parallel for those who live there now, trying to sustain their own "conceits, borrowings, deceptions" against the pressure of the world. Like Pynchon's Oedipa Maas (in The Crying of Lot 49), Liz can only struggle to find some way of making sense of random interruption and disoder in a world of vast systems, picking up loose connections from the words in dictionaries, the images in books and films, and a brief love-affair with the decent but defeated McCandless, lost amid the disorder of his own papers.

THE GOTHIC novel was imported to America by Charles Brockden Brown, who saw it as a way of dealing with American sentiments and the national weaving of myth and history. American Gothic, he said, would not need to use European castles or feudal manors, but could be based on "a series of adventures growing out of the conditions of our country." Gaddis' carpenter's Gothic novel is itself concerned with the conditions of the country, which are dark and destructive, and impose terrible pressures on the mind and sensitivity. The world outside and beyond Liz is a world of dark imperialism, shrouded in the ignorance of an age of raging fundamentalist faiths. Paul promotes the cause of the media evangelist the Reverend Ude, who attacks evolution and science, abortion and Marxism, in a mission that is a cover for the exploitation of mineral resources in Africa. The old Heart of Darkness is as dark as ever, a continent where fanatics from every faith conduct their jihads in a new era of mindless revealed religion, as if hungry for apocalypse.

As in Gaddis' earlier novels, the characters are ritual talkers, makers of tales and interpretations which compete to structure the accumulating plots and conspiracies of life. All stories conceal some falsehood. Liz herself seeks "some hope of order restored, even that of a past itself in tatters, revised, amended, fabricated in fact from its very past to reorder its unlikelihoods, what it all might have been . . . ." Both Liz and McCandless write fictions, but they are powerless before the fictions of life, the conspiracies that do have power, and in their ever-unravelling complexity take us to the book's bleak ending.

But, like Gaddis' other novels, Carpenter's Gothic has a marvelous stylistic precision and a sharp satirical bite. Gothic fiction has always been about reason's struggle with extremity. It has also shown the power of as well as the defeat of the inventive process of fiction. Gaddis' own fine patchwork of "conceits, borrowings, deceptions" has rebuilt the form to write a novel of our own irrational fundamentalist and apocalyptic age. This fine and tightly-made book shows again that Gaddis is among the first rank of contemporary American writers.