For Saul Bellow, 1964 was a breakthrough year. With the publication of his sixth book, Herzog, Bellow went from being a favorite of the critics and a select circle of readers to the ranks of novelists whom the public knows and likes.

Herzog earned Bellow his second National Book Award to go along with the one he had received a decade earlier for The Adventures of Augie March. But it was a commercial success as well, staying on the New York Times bestseller list for 42 weeks and reaching number one soon after its 1964 publication.

After years of failing to earn out his advances, Bellow was, as his biographer James Atlas has noted, suddenly a wealthy man. The 142,000 hardcover copies that Herzog sold even increased the demand for paperback rights to Bellow’s earlier books.

Today, few doubt that Bellow merited the Nobel Prize he received in 1976, but on Herzog’s 50th anniversary, it’s worth considering why this particular Bellow novel achieved such popularity. Andy Warhol’s “Brillo Boxes,” Lyndon Johnson’s war on poverty, and the Mississippi Freedom Summer were all part of the nation’s culture in 1964. In that innovative company, Herzog was decidedly old fashioned—and by most measures not a book likely to generate blockbuster sales.

Bellow’s novel revolves around Moses Herzog, a middle-aged former professor struggling to cope with a life that has gone horribly wrong in his eyes. Divorced from a wife who has slept with his best friend, uncertain of whether he will ever get back into the academic world he abandoned, and living apart from a daughter he deeply loves, Herzog is filled with anxiety.

“If I am out of my mind, it’s alright with me thought Moses Herzog,” are the opening lines of Bellow’s book, and they are followed by a description of Herzog’s day-to-day life. “He had fallen under a spell and was writing letters to everyone under the sun,” Bellow observes. “Hidden in the country, he wrote endlessly, fanatically, to the newspapers, to people in public life, to friends and relatives, and at last to the dead, his own obscure dead, and finally the famous dead.”

The letter writing, a variation on the 18th-century tradition of the epistolary novel, reminds the reader that Bellow is not trying to be innovative with the structure of Herzog, nor is he seeking to make Herzog a hero with whom it is easy to identify. Moses Herzog lacks the common touch as well as the capacity for high drama.

Yet, despite his Ph.D.-heavy interior life, Herzog’s problems captured the interest of the book-buying public in 1964. The novel’s popularity led Pete Hamill to profile Bellow for the New York Herald Tribune and Gloria Steinem to do the same for Glamour.

What made the appeal of Herzog so wide ranging were in no small measure Herzog’s insights into ’60s culture during the period between the assassination of John Kennedy and the nation’s full-scale involvement in the Vietnam War. Herzog’s descriptions are mini-critiques of his times.

In the New York City courthouse, while waiting to meet with his own lawyer, Herzog sees one poor defendant after another railroaded by the justice system. During a visit with his daughter, who now lives far away from him in Chicago, he experiences the price sexual freedom exacts on the children of divorce, and noting the growing impact of money on politics, he realizes with great sadness how intellectuals like himself are increasingly “lost in the arms of industrial chiefs and billionaire brass.”

The result is the kind of overview of the country missing in so many novels that revolve around a vulnerable, central figure absorbed by his own troubles. In this case the overview of the novel reflects Herzog’s desire to reach beyond himself. “He must live. Complete his assignment, whatever that was,” Herzog tells himself as he starts to get over the depression into which he has fallen.

Herzog belongs to a long line of American intellectual heroes who come to look down on the purely intellectual life. Like Ishmael in Moby Dick, who asserts that a whale ship was his Harvard and his Yale, and Thoreau in Walden, who finds his bean field endlessly fascinating, Herzog opts for a life built on contact with the everyday. He is not satisfied to end up as a recluse.

By the last scene in Bellow’s novel, Herzog has stopped his compulsive letter writing. His difficulties have freed him, not imprisoned him. At the country home in Massachusetts that he previously abandoned, he is waiting for the arrival of the woman who has become his new lover, and to welcome her, he has gone into his garden and picked a bouquet of roses and day lilies.

Herzog’s decision to pick the flowers rather than worry over what will happen next is clarifying. He has not, like a modern Emerson, surrendered himself to nature, but he has, at last, found his instincts worth trusting. “At this time he had no single message for anyone. Nothing. Not a single word,” Bellow observes.

The result is a meaningful silence and moving conclusion, and in accepting the National Book Award for Herzog, Bellow spoke directly about the value that becoming invested in daily life held for writers like himself. “Literature has for several generations been its own sources, its own province, has lived upon its own traditions, and accepted a romantic separation or estrangement from the common world,” he declared. “Without the common world the novelist is nothing but a curiosity and will find himself in a glass case along some dull museum corridor of the future.”

Bellow’s call for personal engagement was very different from the call to political engagement that during the ’60s led the young to join the civil rights movement and later the anti-Vietnam War movement. The triumph of Herzog was that it let readers see that such personal engagement was equally crucial to the well-being of the country.Nicolaus Mills is professor of American Studies at Sarah Lawrence College and author of Winning the Peace: The Marshall Plan and America’s Coming of Age as a Superpower.