In 1936, F. Scott Fitzgerald's career was on a downward slope. His fourth (and final) novel published two years earlier—Tender Is the Night, which he considered his greatest achievement—was met with middling reviews and sales. Afterward, he was burnt out on writing, worried that he'd peaked at a young age, and feeling unfulfilled both creatively and personally. Fitzgerald was 39. He'd begun to crack up.

So Fitzgerald's writing turned inward. In "The Crack-Up," published as a trio of essays in Esquire in early 1936, the struggling author analyzed everything in his life and psyche holding him back. He described himself as "a cracked plate, the kind that one wonders whether it is worth preserving."

Seventy-seven years later, Robin Pecknold, the 27-year-old frontman of Fleet Foxes, stumbled upon the essay for the first time, buried in a collection of the famed author's assorted work. "It was just kind of tucked in there with 25 other essays," Pecknold tells me of the book in which he first found "The Crack-Up." "There's a lot that resonated with where I was at in my life around that time... [H]im feeling tired or wrecked, or having to over-perform in daily life, and finding new things to care about." Fitzgerald's very personal words rang true for Pecknold, who just a year before had put his critically acclaimed band on hold at the peak of their career.

Shawn Brackbill

In 2008, when Pecknold was just 22 years old, Fleet Foxes' self-titled debut was met with critical acclaim and commercial success, eventually earning Gold status five years after its release. Its influence on the culture was more immediate; it represented the natural course for the subgenre of "indie folk," which had begun simmering in the late '90s and early aughts. Fleet Foxes ushered it into the mainstream with a simple authenticity and vocal harmonies that returned the genre to its more natural roots. The band followed that up with the equally stunning Helplessness Blues in 2011, which hit No. 4 on the Billboard 200. But after touring that album, Pecknold started to break—and Fleet Foxes followed suit with an indefinite hiatus in 2012.

"I [had been] playing music basically from age 14 to 26," Pecknold says. "Then I was going back to school, and I was looking for other things besides music to do, because I've been really one-dimensional up to that point. I guess I was wondering if if I would ever make music my main focus again." Lost in his own head, Pecknold retreated from the public eye, focusing on himself independent from his music that made him an indie hero. "Why would music ever give someone trouble?" he asks. "It's just, like, sound. But the other stuff around it can make you—or at least made me—wither a little bit and want to retreat."

"Why would music ever give someone trouble?" Pecknold asks. "It's just, like, sound. But the other stuff around it can make you—or at least made me—wither a little bit and want to retreat."

It was during that retreat from music, when he enrolled at the Columbia University School for General Studies, that he first read Fitzgerald's essay. He read and re-read the piece. He keeps a marked-up version at home, and has a copy of the original issue of Esquire in which the essay first appeared—a gift from his girlfriend at the time, who bought it for him for his 30th birthday.

One idea in particular that inspired Pecknold is Fitzgerald's notion of the duality of life. "The test of a first-rate intelligence is the ability to hold two opposed ideas in the mind at the same time, and still retain the ability to function," Fitzgerald wrote. It's one of the most famous lines from the essay, it it was something Pecknold had been thinking about music, too. "Sometimes my emotional response toward music validates it," Pecknold says. "Other times I'll think, 'Everything has been done. I should do science.'"

At times Pecknold felt like there was no way to move forward with music, but then he'd feel the exact opposite—that if he was being creative and the music felt right, then that was the only justification for writing songs. He'd found some comfort in a conclusion Fitzgerald reaches in his essay. "I realized I needed to find a middle ground," he says. "I'm just here to experience things. Just an arrow—like [Fitzgerald] said—like an arrow shot from nothingness to nothingness. And I think you have to find some middle way to move forward. You have to hold those two ideas in balance."

After four years away from the band (during which former drummer Josh Tillman launched his own successful career as Father John Misty), Pecknold finally returned to writing songs with Fleet Foxes. The result is a new Fleet Foxes album, out Friday. Crack-Up takes its title from the essay that served as an emotional and philosophical guide for Pecknold, and the band returns as one shaped by Pecknold's chaotic mental state over the last six years. It's a complex album—in no way the pretty, accessible folk music the band was making nearly a decade ago. There are false endings, neurotic song changes, juxtaposed melodies and rhythms. These are songs made by a man who had been considering the textbook theories of music (Pecknold took some music classes at Columbia). Quite specifically, Pecknold incorporated Fitzgerald's concept of duality into his songs.

"A lot of the polyrhythms in the album come from that idea," Pecknold explains. "There'll be one rhythm in the left speaker and one in the right speaker—like a six-pattern and a four-pattern played against each other. I was just trying to have little musical references to that idea that I encountered in the essay. And then there's a lot on the record about perception, and that I feel like what that essay is mainly about is 'life is as you perceive it' or 'life is as you make it.'"

Having stepped away from professional music and done the opposite of what he was doing with Fleet Foxes, Pecknold was able to do what Fitzgerald never did—repair his crack-up. "I feel like I have a lot of stored up vitality, or energy for it—I don't feel worn out," Pecknold says. "I wanted to get better, and I didn't feel like continuing to do it as we were doing. Now, I'm seeing things in less of a black-and-white sense. You have to delude yourself into thinking that what you're doing is valuable to have the vitality to keep doing it. And that's not a bad thing."

A version of this article appeared in the June/July '17 issue of Esquire.