Those with whom Eisenberg first shared the story found it overbearing. “I know! I know! Don’t tell me!” is how she characterized their response. Critics were similarly resistant, and yet the book has outlasted these objections and feels especially prescient at a moment when America’s willful ignorance on every matter from climate change to its own racial history poses a civilizational threat. “I was born at a moment when the world thought, O.K., this is the end of fascism,” she told me. “I mean, it was a bit of a stupid thing to think, obviously, but I never believed that we would be seeing such a resurgence of it, let alone that America would be joining exuberantly in.”

One evening this summer, Eisenberg and Shawn went to see a new production of “Marie and Bruce,” Shawn’s play, written in 1978, about an operatically dysfunctional married couple, at Jack, a performance space in Clinton Hill, Brooklyn. Wedged in among the millennials, several of whom turned to steal glances at the author and his girlfriend, they were the oldest audience members by several decades. (They were also pretty much the only ones there without any conspicuous tattoos.) “If only we’d had a crowd like this at the premiere,” Eisenberg said before the performance began, making touching use of the first-person plural. Indeed, the couple seemed the inverse of the one on stage: mutually affirming and compassionate and bracingly preoccupied with matters beyond their own immediate well being. A few days earlier, Eisenberg showed me what she described, half-jokingly, as her shrine to Wally, a shelf in a narrow downstairs office that houses, among other pieces of iconography, a Wallace Shawn action figure still in its packaging, a Rex-the-dinosaur Pez dispenser (Shawn provides the voice for the character in the “Toy Story” movies) and a photo of Shawn in full costume — outsize ears, warty, wrinkled flesh — for his role as Grand Nagus Zek in “Star Trek: Deep Space Nine.” The original audience for “Marie and Bruce,” they explained, was older, stuffy and coldly unreceptive to Shawn’s vision of marriage as a Dante-esque ordeal. Tonight, as the lights came up and Marie (Theda Hammel) began unleashing her fire hose of invective against the timorous Bruce (Gordon Landenberger), the house was immediately overcome with laughter.

Eisenberg and Shawn do not have children, and it is tempting to draw a connection between this fact and their pronounced anti-curmudgeonliness: Perhaps those without a direct personal link to the next generation are naturally more interested in the perspective of the young. “Your Duck Is My Duck,” as you would expect of a book by a writer of 70-plus, is full of a sense of impending expiration; several of its aging characters, struck by the realization that very soon no one will remember the things that they remember, have become ardent students of their own pasts, sifting the years for a faithful account of what their lives will have meant. At the same time, it is also a book about the future and a yearning for, as Eisenberg puts it, “what was just about to be the world’s very latest moment,” a phrase that nicely captures the minute-by-minute anticipation with which ordinary life has been imbued.

These countercurrents merge in the collection’s final story, “Recalculating,” another late-career masterpiece. At a memorial service in London, a middle-aged dance instructor named Vivian encounters the nephew of her deceased former lover and later goes to bed with him. In lesser hands, the one-night stand might have been presented as a desperate and pathetic bid to recapture the past. Instead, Eisenberg shows us how Adam, the nephew, is equally drawn to Vivian, who embodies the world of his uncle, a man who escaped the stifling world of his Midwestern childhood, as Adam himself is now trying to do, and made a new life of sexual and artistic freedom abroad.

Vivian, who does not have children and whose early ambitions to become a dancer were never realized, is full of retrospective longing: “There was always the feeling that one would get around to being young again. And that when one was young again, life would resume the course from which it had so shockingly deviated.” But this sense of loss never curdles into resentment at those with more time than her. On the contrary, she recognizes that her young students, for all their vitality, harbor “sorrows that might still be reversed or at least compensated for.” In a shrewd twist, when Vivian and Adam meet again decades later, it is she who feels a twinge of pity for him, with his potbelly and thinning hair.

Eisenberg and Shawn were thrilled by the performance. After it was over, they stayed to praise and congratulate the young cast and continued to enthuse about it as they made their way to a nearby restaurant in the pouring rain. As they were approaching their destination, Eisenberg, who was wearing a black Issey Miyake trench coat she bought two decades ago (and for which she’d received several compliments that evening), stepped over a rain-swollen gutter into the path of an oncoming car. Shawn reached out to pull her back. “That would’ve been ironic,” she said a bit later, as though she were only now processing the incident. “If I’d been run over after watching ‘Marie and Bruce.’ ”

They made it to dinner in one piece. Eisenberg started with a martini (“You never know what you’re going to get with wine”); Shawn, who rarely drinks, had a seltzer. By way of the new collection they got on to the subject of aging. Eisenberg, who was well into one of the fallow periods that have punctuated her creative life, hadn’t written anything for more than a year. She wondered if she would ever finish another story. Who knew what would give out first — her body or the world? Still, for someone strapped to an explosive device, she was in a buoyant mood.

“People always talk about how horrible old age is, but I couldn’t disagree more,” she said, the candlelight glimmering on her inclined face. “I find age is as intense as adolescence. You know you could hurtle off a cliff at any second. And because of that there’s a sense of destiny, of apprehending things, of love that isn’t available — or wasn’t available to me — earlier. You feel: I’ve survived this ordeal, and now I don’t have to worry. I know how my life has worked out. All the anxiety that I put into the hard questions has fallen away. I can take my satisfactions where they are.” She looked down at her plate of clam toast with pancetta. “I can enjoy my supper.”