WASHINGTON — Washington.--RABBIT HAS COME to rest as he should have from heart failure at an early age, a death brought on by his undisciplined surrender to the temptation of petty indulgences. The question is, is Rabbit us?
''Rabbit at Rest,'' John Updike's fourth and final novel about Harry ''Rabbit'' Angstrom, begins at a Florida airline terminal. Rabbit, 55 years old and 40 pounds overweight, is suffering intimations of his terminal illness -- chest pains -- and an irresistible craving for a candy bar. The book ends, many such surrenders later, with Rabbit hospitalized, sagging toward a death that might have been forestalled by sensible habits or serious surgery, which he rejected.
The preceding installments in this unique literary genre -- this epic of the mundane -- were ''Rabbit, Run'' (1960), ''Rabbit Redux'' (1971) and ''Rabbit is Rich'' (1981). Mr. Updike is not a novelist of ideas but of mingled domestic atmospheres and social intimations. But the mingling makes it reasonable for the readers who have made these books best-sellers to ransack them for social diagnoses. Mr. Updike's timing causes them to be seen as summations of decades.
When we first met Rabbit, he was 26. It was 1959 and Mr. Updike remembers that ''Kerouac's 'On the Road' was in the air, and a decade of 'dropping out' about to arrive, and the price society pays for unrestrained motion was on my mind.'' Mr. Updike kept returning to Rabbit to explore America's ''unease.''
The Rabbit we now rejoin (it is December 1988) is preoccupied with disasters, such as the terrorist destruction of the airliner over Lockerbie and, later, hurricane Hugo. ''He, too, is falling, helplessly falling, toward death.'' Death by potato chips.
The unbearable heaviness of being Rabbit is both physical and spiritual. He is fat, emotionally logy and oppressed by his vulgar gluttony. He has taken to the desultory reading of history, ''that sinister mulch of facts our little lives grow out of before joining the mulch themselves, the fragile brown rotting layers of previous deaths.''
Mr. Updike has now written 1,700 pages about this emotionally stunted, intellectually barren, morally repulsive egotist whose self-absorption lacks even the fascination of large scale. His life's work is an inherited Toyota dealership (''Who could ask for anything more?'') that is taken from him by the no-nonsense Japanese after his son embezzles from it to feed his cocaine habit. That addiction is convincingly depicted in all its hair-raising squalor, but it is, in a sense, less unnerving than Rabbit's collapse of will as he nibbles himself to death.
Rabbit, like all of us, is moved by a mixture of physical and moral promptings. But in Rabbit, the latter are so weak and the former so base, it is a tribute to Mr. Updike's craftsmanship that we want to watch as Rabbit becomes a comprehensive failure, as husband, father, businessman, man.
Mr. Updike is a realist in the American tradition of Theodore Dreiser, Sinclair Lewis and, recently, Tom Wolfe. Mr. Updike does not believe, as many less-read writers seem to, that American life is so absurd that it defeats the conventions of realism.
Realism can be angry, but only up to a point. There must be a residue of caring, even affection, to move a writer to engage reality. Sinclair Lewis may have loathed George F. Babbitt and his hometown of Zenith, or the smallness of Gopher Prairie's Main Street, but Lewis was angry because they fell short of hopes he had and standards they should have had.
However, realism is not literary photography: It need not be literal, or even in a sense, realistic.
The New York Times reviewer calls ''Rabbit at Rest'' Updike's ''powerful critique of America'' and also a ''supremely eloquent valentine to his country.'' The Washington Post reviewer calls it ''a happy book; an exultant hymn to the inexhaustible vitality of America.'' Well.
Mr. Updike calls it ''a depressed book about a depressed man, written by a depressed man.'' John Updike knows that a novel is like a child: It has life of its own. The author cannot control how it and the world affect one another. Toward the end, the author has Rabbit leading the Fourth of July parade dressed as Uncle Sam, and Rabbit occasionally lets loose political sentiments, about falling bridges and rising debts. But Mr. Updike may not have much on his mind other than the literary challenge of casting a cool eye on the life, and now the death, of a middle-class man.
But not a representative man -- not a metaphor for America. Perhaps ''Rabbit at Rest'' can be read as a cautionary tale for America the sclerotic, its arteries clogged by dumb consumption. But Mr. Updike, who is one year older than Rabbit and grew up where Rabbit lived, in southeastern Pennsylvania, may just be interested in, and perhaps depressed by, mortality.
Is America mortal? Maybe, even probably, but not imminently. As Mr. Updike once said, ''People run down, and they confuse their condition with the world's.''