BOOK REVIEW / SHORT STORIES : Facing the Realities of Aging, Death : THE AFTERLIFE AND OTHER STORIES <i> by John Updike</i> , Alfred A. Knopf $24, 316 pages

John Updike a geezer? Impossible. Only yesterday, it seems, he was a boy wonder fresh out of Harvard by way of the New Yorker, dazzling us with moves in prose as fluid as young Rabbit Angstrom’s on the basketball court.

Yet Rabbit is dead, after faking and dribbling his way through four novels, and I realize that I have been reading Updike, his creator, all my adult life. “Born in Shillington, Pa., in 1932�--that standard biographical line has appeared in each of Updike’s 40-plus books; now, in his 11th collection of short stories, it tells a tale of its own.

Updike, in these 22 new stories (17 of them reprinted from the New Yorker), faces up to the inexorable arithmetic. Most of his protagonists, too, are in their 60s. Sex and death are still his preoccupations--as they must be for a WASP male writer denied more specialized sources of material--but the balance has clearly tilted toward death.

Sex is recalled like a delirium after the fever has passed. Updike’s men try to remember the visions love brought to them, but the only solid evidence is the debris littering the sickbed: children, ex-wives, divided property, self-distrust, regret. Death, on the contrary, is close and real, though often oddly reassuring in its approach.

“Perhaps an object could travel faster than the speed of light, and we each have an immortal soul. It didn’t, terribly, matter,� one character muses. “The headlines in the paper, trumpeting news of campaigns and pestilences, seemed directed at somebody else, like the new movies and television specials and pennant races and beer commercials--somebody younger and more easily excited, somebody for whom the world still had weight.�

Updike expresses this lightening, this shuffling-off of mortal avoirdupois, by revisiting places and people we have seen before. The town of Olinger; the city of Alton; a Massachusetts beach settlement like the Tarbox where “Couples� cavorted, now haunted by AIDS and outbreaks of tick-borne Lyme disease; above all, the 80 Pennsylvania acres where “The Centaur� and “Of the Farm� took place--each is viewed from a new angle.

“A Sandstone Farmhouse,� the longest story here, is a meditation on the transience of people, the mutability of places and the stubborn bonds between them. The aging narrator’s aged mother dies--a sign that he must follow. Yet her life seems more meaningful to him than it did before; the religious impulse to sum things up is incorrigible in Updike’s characters, whether or not God, too, is keeping score. The mother’s house in the country, which the son once was glad to escape, now “needed him. Only he understood it. . . . He had always wanted to be where the action was, and what action there was, it turned out, had been back there.�

Richard and Joan Maple, long divorced and remarried, meet again to witness the birth of their first grandchild, and the erotic, contentious past they have shared crackles to life in the brush of their contact, like static electricity. Allen Dow, the mother-fixated teen-ager in Updike’s 1962 story “Flight,� is now hollowed out by his mother’s absence. Fat and lonely at 60, he eats compulsively to still “the suppressed panic� inside him, “not so much the fear of death as the sensation that his life was too small. “

Dread appears elsewhere in this collection--few stories express the horror of a comfortable but loveless old age better than “Short Easter.� More typical, though, is the playful title story. The “afterlife� could be a couple’s post-retirement idyll in England; it could be the heightened sense of life a visitor experiences after a near-fatal fall down a flight of stairs; but it could simply be old age itself, a release from the pressures and worries of overextended youth.

Are Updike’s powers aging along with him? Not much. We have come to take his stylistic brilliance and structural ingenuity for granted, and some of his habitual gestures--the Greek mythology, the swatches of travelogue, the cool, brittle encounters between lovers--seem like tics.

Still, the golf story here, “Farrell’s Caddie,� is a classic of its kind; and it’s worth noting that Updike does his best work in “The Afterlife� not when he repeats himself, in the sexual comedies, but when he bravely surveys the narrowing new territory that the years have left him.