As an author of 11 books, Mr. Jay earned enthusiastic reviews. His last book, titled (in part) “Matthias Buchinger: ‘The Greatest German Living’” (2016), was pronounced awe-inspiring by The Los Angeles Times, beguiling by The New York Review of Books and tantalizing by Bookforum. Writing in The New York Times, Charles McGrath described Mr. Jay as the “master of a prose style that qualifies him as perhaps the last of the great 19th-century authors.”

Richard Jay Potash was born on June 26, 1946, in Brooklyn, the older of two children of Samuel Potash and Shirley (Katz) Potash and the grandson of Max Katz, a Hungarian-born accountant who was also an accomplished amateur magician. The family soon moved to Elizabeth, N.J.

Ricky first performed magic in public at a magicians’ association picnic in Sheepshead Bay, Brooklyn, at the age of 4. At 7, he appeared on a television show called “Time for Pets,” plopping a guinea pig into a top hat and appearing to turn it into a chicken. The sign behind him said “world’s youngest magician.”

“It’s safe to say that my parents just didn’t get it or didn’t get me, and we had no rapport,” he recalled in the film documentary and similarly in a 1993 profile in The New Yorker, explaining why he deliberately refused to talk about them or his childhood in any detail. His one warm memory of his mother and father, he said, was their agreeing to hire Al Flosso, a magician who was a hit on “The Ed Sullivan Show,” to perform at his bar mitzvah.

And then, thanks to “the audacity of youth,” he said in the documentary, he was gone. “I left home very early and basically never returned,” he said.