PATRIMONY A True Story By Philip Roth Simon and Schuster. 238 pp. $19.95

ONE OF the central facts of contemporary American life is that both our living and our dying tend to be more prolonged than they were as recently as a generation ago, yet one of the oddities of our contemporary literature is that most of our writers shrink away from this important and provocative subject. Americans prefer to face the reality of death by denying it, by disguising it in euphemism and prettification; American writers, if we are to believe what they write, prefer to pretend it simply doesn't exist.

So quite apart from the merits of Patrimony, which in fact are considerable, Philip Roth deserves both praise and gratitude for meeting death head-on. This is a work of nonfiction by an author whose novels and stories have always walked a fine line between fiction and "fact," indeed at times have teetered so uneasily on that line as to raise serious questions about the territory they occupy. But in Patrimony, though it yields occasional evidence of poetic license, Roth is on firm ground; his subject is the death two years ago at the age of 86 of his father, Herman Roth, and he writes about it with his eyes wide open, facing the facts unflinchingly and unsentimentally.

Death is never pretty, but it's all the less so at a time when so many of us survive into a state of enfeeblement and then become the victims of afflictions that expose us to the various insults of institutionalization. Herman Roth never got so far as the nursing home or even a protracted hospital stay, but the brain tumor that finally killed him nonetheless exacted a dear toll in debilitation and loss of dignity. For his younger son, Philip, who was in his mid fifties as this process unfolded, being both witness to and participant in his father's dying was an almost unremittingly painful experience; in Patrimony he gives us the full measure of that pain, but he also alleviates and ennobles it by giving us the joy as well.

This is not to say that Herman Roth was a joyful man in the sense the term usually conjures up; he was cranky, stubborn, primitive, difficult. But he was also "talkative, energetic, gregarious, very much the forceful insurance man whose years in Newark as an agent and assistant manager had familiarized him with nearly every Jewish family in the city." Above all else he was alive, and in his son's portrait he emerges as one of the genuinely indomitable figures in American literature.

"Dying is fine," e.e. cummings wrote, "but Death? . . ." by which he meant that dying is a living process while death is merely dead. Roth understands this, and tells the story of his father's final months not as a dirge for the departed but as a celebration of living; following the writer's natural bent, he seeks to bring his father back to life -- to give him a kind of immortality -- through the printed word. Even when he tells the coldest truth about his father, he celebrates him:

"He could never understand that a capacity for renunciation and iron self-discipline like his own was extraordinary and not an endowment shared by all. He figured if a man with all his handicaps and limitations had it in him, then anybody did. All that was required was willpower -- as if willpower grew on trees. His unswerving dutifulness toward those for whom he was responsible seemed to compel him to respond to what he perceived as their failings as viscerally as he did to what he took -- and not necessarily mistakenly -- to be their needs. And because his was a peremptory personality and because buried deep inside him was an unalloyed nugget of prehistoric ignorance as well, he had no idea just how unproductive, how maddening, even, at times, how cruel his admonishing could be."

He was at heart a kind man, and he cared passionately about his family and his vast circle of friends, but his was a rough kindness that often left its recipients more bruised than bettered. Criticism and unsolicited advice flowed from his lips as water from a bottomless well, in particular if the beneficiary was a woman important to him: first his wife, Bessie, then, after her death, Lil, the woman with whom he shared his apartment. He was possessed by an irresistible urge to fix things up, to make things right, and it never crossed his mind that he was more a nuisance and a scold than a help. An especially lovely moment comes late in Roth's tale when, having been told by his father that Lil "can't even buy a cantaloupe," the son at last has it up to here and explodes:

"Look, a cantaloupe is a hard thing to buy -- maybe the hardest thing there is to buy, when you stop to think about it. A cantaloupe isn't an apple, you know, where you can tell from the outside what's going on inside. I'd rather buy a car than a cantaloupe -- I'd rather buy a house than a cantaloupe . . . I'll tell you about making a mistake with a cantaloupe: we all do it. We weren't made to buy cantaloupe. Do me a favor, Herm, get off the woman's ass, because it isn't just Lil's weakness buying a . . . cantaloupe: it's a human weakness."

That passage is one of several in which Roth simply cannot resist the urge to amuse; others include a geriatric musicale in Florida, a ride with a paranoid, parricidal cab driver in New York, and a dinner with a refugee from Nazi Germany whose memoir of the Holocaust turns out to be rank pornography. If these and other scenes are meant to lighten the way along Herman Roth's passage to the grave, even more they are meant to conjure up the energy and spirit of his life: to place him where he belongs, as one in the community of Jewish men and women whose "real work, the invisible, huge job that he did all his life, that that whole generation of Jews did, was making themselves American."

That comment, true though it most certainly is, comes during one of only two sections of Patrimony that ring false: a long telephone conversation with a friend that clearly was therapeutic for Roth but is largely a roadblock for the reader. The other is the book's conclusion, in which Roth resorts to dreams in an attempt to give his story conclusive meaning; what he seems not to understand is that the story contains its own meaning, and that explication -- especially through the clumsy use of dreams -- merely muddies it.

The point that matters is made more than 50 pages earlier. "He wasn't just any father," Roth writes, "he was the father, with everything there is to hate in a father and everything there is to love." It is the old universal story, and no dreams or exegeses are needed to tell it; all we need are the facts, and in the heart of his narrative Roth gives us these with clarity, understanding and love.