214 pp. $5.95.

"AT LEAST some of the time, the world appears to me as a painting by Hieronymous Bosch; were I to follow my conscience then, it would lead me out into the desert with Marion Faye, out to where he stood in The Deer Park looking east to Los Alamos and praying, as if for rain, that it would happen:'... let it come and clear the rot and the stench and the stink, let it come for all of everywhere, just so it comes and the world stands clear in the white dead dawn.'"

wow.

How do you live with that?

But then you don't. And neither do you kill yourself. For the matter is not, as they would have us believe, one of life and death. It is all only the difference between death in death, death in life. In that, there is no difference.

You just Play It As It Lays. Which is the title of Joan Didion's new novel. In which she follows the conscience ( conscience? try consciousness, a better word it seems, though not one she would use) that leads her to rip open, ever so neatly, ever so tellingly, a world whose center no longer holds, America in its southwestern and Californian apocalypse, the source for most of her essays in her brilliant collection, Slouching Towards Bethlehem, and now the setting for the new novel.

Play it as it lays, Harry Wyeth told his daughter. Wyeth, a gambler in the respected, dead-end tradition of the pioneer. Losing their home in Reno, he moved his wife and child to Silver Wells, Nevada, there built a motel "that would have been advantageously situated at a freeway exit had the freeway been built." Maria grows up, in turn loses, in Los Angeles, in Vegas, in Marriage and at motherhood. Ends up in Neuropsychiatric. "I was raised to believe that what came in on the next roll would always be better than what went out on the last. I no longer believe that."

Her father's exhilaration and hope. Her mother's pain. Her own despair. Are all behind Maria. She is so much the anesthetist's victim that her only sense of being alive comes from "the physical flash of walking in and out of places, the temperature shock, the hot wind blowing outside, the heavy frigid air inside."

THERE is simply no other evidence that Maria's world-full of Hollywood-types that "registered on her only as a foreigner or a faggot or a gangster"-is capable of supporting any deeper sense of life. The very superficiality of its pretended pain mocks any postures of feeling it cares to feign.

"'BZ, you've planned this to torment me,'" a homosexual masseur protests. "He stood on the deck, holding a plastic lemon at elaborate arm's length. 'You couldn't possibly buy artificial lemon juice, someone left it here, it's a bad joke.'"

"Leonard's in New York for ten days," Helene complains to Maria. "I don't mind if I'm out of town, but if I'm in town, and Leonard's not, I feel almost... frightened." Leonard is Helene's hairdresser.

But somehow Maria jumps the track, junks the game.

"'You've been brushing it wet,' the hairdresser said, lifting a strand of Maria's hair and letting it drop with distaste.

"'I guess so.' Maria could never keep up her end of the dialogue with hairdressers."

"At a dinner party, a group of friends." Maria's estranged husband, a film director, lets go with a few complaints of his own. "Maria would say that they were not her friends, but Maria has never understood friendship, conversation, the normal amenities of social exchange." And later. The two in bed, he shouts at her, "Well go to sleep, cunt. Go to sleep. Die. Fucking vegetable." Fucking vegetable, he shouts at her in bed, little realizing that in her catatonia Maria is only holding a mirror up to the more frenetic stiffs surrounding her.