As a budding writer in the mid-1960s, Paul Auster decided to keep a diary, but he "stopped after just two days," he says in his new book, "feeling uncomfortable, self-conscious, confused about the purpose of the undertaking." A half-century later, he's long since overcome his youthful reticence.

Auster is best known for his unsettling and addictive novels, but over the past 30 years, he's also written nonfiction about his career's slow start, his love life and his experiences with randomness. In 2012, he published a memoir titled "Winter Journal," which deals with the physical experience of growing older, and this fall he's back with another memoir about the first two decades of his life.

"Report From the Interior" is divided into three parts. In the first section, the book's strongest, Auster surveys his 1950s preadolescence. He's motivated to do so, he writes in the second-person voice he uses throughout the book, "not because you find yourself a rare or exceptional object of study, but precisely because you don't, because you think of yourself as anyone, as everyone."

Though this seems like a rather lifeless conceit, it makes for a funny, touching and winningly unsentimental 100 pages. Auster recalls his first efforts to craft a poem ("a wretched piece of dried-out snot that began with the couplet: Spring is here, / Give a cheer!"); the gulf between white New Jersey suburbanites like the Aus­ters and the African-American families that rented apartments from his father ("you only had to lift your head and look around you to realize that the world was unjust"); and the understanding that the stories we tell one another are full of partial truths (a local businessman promised to introduce young Paul to Whitey Ford, but the man who he passed off as the Yankees pitcher didn't quite resemble his baseball card).

The book's middle is devoted to two films that altered Aus­ter's worldview — 1932's "I Am a Fugitive From a Chain Gang" and "The Incredible Shrinking Man," from 1957. "Chain Gang," he says, awakened him to a host of social justice issues, and "Shrinking Man" made him ponder existential questions. This is a nifty piece of film criticism — enthusiastic and highly personal — although Auster's long plot summaries tend to drag.

Finally, the book's last third is its weakest. In the past 10 years, I've read every bit of prose he's published in book form since the early 1980s — the vast majority of which I'd swear by — and this isn't among his best work. Titled "Time Capsule," the section revisits his epistolary courtship of Lydia Davis, the novelist who would become his first wife, quoting at length from the letters he wrote to her decades ago. He views the garrulous letters as "the only door you have ever found that opens directly onto your past." Reprinting them here, however, does little but confirm that Auster, who would become an economical storyteller, wasn't always so concise.

Kevin Canfield is a writer and critic in New York City.