Tom Wolfe, the best-selling alchemist of fiction and nonfiction who wrote “The Bonfire of the Vanities,” “The Right Stuff” and countless other novels and works of journalism, died of pneumonia in a New York hospital Monday, said his longtime agent Lynn Nesbit. He was 88 years old.

Mr. Wolfe was a nattily clad Southern gentleman, whose trademark white suits and polite demeanor shrouded a rapier wit, a relentless work ethic and an unquenchable curiosity about human nature. For nonfiction and novels alike, he threw himself into...