Though David Foster Wallace is my favorite writer, I’ve never read his final, posthumously released novel, “The Pale King.” My friend Sajid lent it to me in 2011. I have moved to three different cities since then, and the borrowed book remains on my shelf, unread. (Sorry, Saj.) My reason is as simple as it might be obvious and ridiculous: Once I read it, there’s no more Wallace to discover.

I thought about this as I watched “The Old Man and the Gun.” The quiet, unassuming movie about an elder gang of bank robbers stars Robert Redford in what he has claimed will be his final performance.

If it’s truly Redford’s swan song, then it’s a fitting one. The movie feels like a 1970s throwback, with close-ups of his weathered face capturing the camera as his old-world charm imbues the audience with a calm satisfaction. Most importantly, it isn’t showy. The message is simple: Some of us were made to do certain things. In the movie, his character is made to rob banks. In real life, Redford was made to act.

Redford is one of the primary reasons I write about popular culture for a living. One of the first movies I remember truly loving was “Three Days of the Condor.” The image of him in a phone booth, desperately shouting, “Everyone! Everyone is dead!” thrilled me and led me to seek out his other movies. It was the beginning of a lifelong love affair, so the idea of it ending has naturally provoked a multitude of feelings.

I imagine many culture fans are experiencing these feelings lately.

First, there’s the recent spate of celebrity deaths, including David Bowie, Anthony Bourdain, XXXTentacion, Mac Miller, Burt Reynolds, Tom Petty, Fats Domino and so many more. Then, there’s the artists who have announced retirement: Neil Diamond, Joan Baez, Elton John, Ozzy Osbourne and Lynyrd Skynyrd, to name a few. Paul Simon recently completed his final tour and gave a lovely send-off performance on “Saturday Night Live.”

Others seem close to the finishing their careers. Bob Dylan’s inclusion of the usually rare “Like a Rolling Stone” in his newest set lists has prompted some to think he might be wrapping things up. When I see him in concert in November, I’m certainly going to treat it as such.

But is it actually a swan song, or is just another tour for the tireless musician?

The phrase “swan song” is thought to derive from an ancient myth that the birds, silent throughout their lives, belt out one beautiful song. In pop culture, they’re a way of bookending a career, finishing a lifelong story, offering closure to fans. Given that “retirement” can be a fickle thing, we don’t actually have that many. Even an artist’s death often isn’t the end, as greedy record companies dig up old demos and, with no one to stop them, drop them in the public consciousness for a few bucks.

When a swan song is planned (and works), though, it can be transcendent.

Warren Zevon and Leonard Cohen fit into that rarefied category. Both men seemed to know the light was fading, and both wanted to issue one final artistic statement.

When Zevon, the virtuoso songwriter behind tunes such as “Werewolves in London” and “Lawyers, Guns and Money,” was diagnosed with mesothelioma and given a few months to live, he immediately began writing his final collection of songs, “The Wind.”

The album was Zevon giving himself a eulogy. His twisted sense of humor remains present, particularly in his purposely on-the-nose cover of Dylan’s “Knockin' on Heaven’s Door.” You can hear his fading voice faltering in every song, as musicians like Petty, Bruce Springsteen and Jackson Browne help fill in the cracks. On his last song, that black comedy dissipates, and he simply begs his fans to “keep me in your heart for a while” and hopes “sometimes when you’re doing simple things around the house / maybe you’ll think of me and smile.” It’s sad, poignant and real. And he wanted everyone to hear it. According to his biography, he called his manager and said, “I’m giving you permission to use my illness in any way that you see fit to further my career right now.”

Cohen, meanwhile, wasn’t sick — but he prepared for the end as he crafted his 14th album, “You Want it Darker.” Weeks before its release, he told the New Yorker, “I am ready to die. I hope it’s not too uncomfortable.” Weeks after its release, he fell and subsequently died in his sleep.

Perhaps he didn’t know exactly when he’d pass this world, but his final record sure sounds like a final record. Pitchfork’s Stacey Anderson wrote that it “feels like a pristine, piously crafted last testament, the informed conclusion of a lifetime of inquiry.” Throughout, Cohen wrestles with God, former lovers and himself with his startlingly sepulchral baritone, but always offering his sly, signature wink.

The emotional impact of both albums derives in some part from the fact that we know they’re final. They’re the last chapters of two very different books, written by their subjects.

Others are not so lucky.

Prince, for example, left behind a literal vault of material when he met his untimely demise. There’s no goodbye, no final chapter, no self-stylized eulogy to come. Just the slow release of decades’ worth of songs he wasn’t ready to show the world. They’ll pop up on social media outlets with increasingly less fanfare, until they simply become commonplace, as if he were still alive and releasing music.

And consider Carrie Fisher’s fate. The actress died unexpectedly in December 2016, not long after reviving her most iconic character, Princess Leia, for the new Star Wars trilogy. Now, footage she filmed before her death is reportedly being used in the next installation of the series. Regardless of what she might have wanted, she had no control over the end of her artistic narrative.

Examples of both scenarios abound. I don’t know which category “A Pale King” falls into, as Wallace took his own life and left the manuscript with a two-page suicide note for his wife Karen Green, likely in hopes that someone would publish what he’d written. But who can ascribe intention?

After seeing “The Old Man and the Gun” and ruminating on the ways our favorite artists decide to bid farewell, I found an interview in which Redford said that he might not be retiring. It’s a familiar tale. After all, how many retired artists return? Eminem, Jay-Z, Tina Turner, Amanda Bynes and even Audrey Hepburn have made their way back to the spotlight. The problem with living is you always want to say more, even if you’ve got nothing left to say.

It’s a strange feeling to hope one of your favorite living artists chooses to retire before time’s march makes that decision for him. More Redford, at least for this film fan, seems like a good thing.

But the idea of swan songs is they only happen once. Otherwise, they’re just songs.