When Franz Kafka’s name mutated into an adjectival cliché it ceased to be connected in any significant way to his tremendous vision. I can recall precisely when and where the willy-nilly tossing around of his name turned ridiculous: It was the summer of 1995 in a movie theater in central Jersey. The movie was a menagerie of mental defects based on a novel of galactic stupidity—Congo by Michael Crichton. In a plot that involves homicidal gorillas, one cipher says to another cipher that their circumstances are Kafkaesque, by which the hamstrung scriptwriter—Crichton himself—presumably meant “strange.” Aside from the clangorous dropping of Kafka’s name, I don’t remember much about the movie, but I’m certain there was nothing truly Kafkaesque about it. Poor Franz—the inimitable seer of modernity without whom twentieth-century European literature would be a weakened affair—had come to be associated with either mere strangeness or else with killer apes.

"The deeper realm of sexual life is closed to me,” Kafka wrote.

Of course the promiscuous use of “Kafkaesque” was common long before Crichton and has continued long after. In 1974, Philip Roth wrote that the great man’s name “is plastered indiscriminately on almost any baffling or unusually opaque event that is not easily translatable into the going simplifications.” Just two weeks ago in The New York Times, a reviewer tried to get away with saying that a first-time author’s work contains “a realm of blackness reminiscent of Kafka.” One might as well liken the writer to Dante—such facile vagueness can mean nearly anything and so instead means nothing. There are myriad and overlapping hues of darkness in Kafka, along with myriad and overlapping hues of comic irony—he is much too multitudinous for the haphazard applying of his name whenever a situation isn’t sunny.

Kafka’s genius is easily snatched for misappropriation because it asserts itself in shadows. A vision of existence as seemingly cryptic and complex as Kafka’s inevitably becomes a strip of flypaper to catch any interpretation that buzzes by it. In 1952, literary philosopher William Hubben wrote of Kafka that “there remains something enigmatic about him that eludes classification,” and in the ensuing decades he has become, with Samuel Beckett, the go-to guy whenever someone wishes to comment upon enigmas. In his introduction to Kafka’s Complete Stories, Updike contends that it is Kafka’s “extrapolations from his experience of paternal authority and naysaying … that define the word ‘Kafkaesque.’ Like ‘Orwellian,’ the adjective describes not the author but an atmosphere within a portion of his work.”

But what about the other portions, those not easily connected to patriarchal terrorizing? Unlike “Orwellian”—which has as its principle source only two slim and unambiguous novels—“Kafkaesque” must pull from scores of stories, fables, parables, and aphorisms, three incomplete novels, 3000 pages of letters and diaries, and, contrary to Updike’s opinion, forty years of the author’s heart-wrecked life—one reaved by hypochondria, insomnia, acute sensitivity of hearing, and the tuberculosis that killed him. In Franz Kafka: The Poet of Shame and Guilt, the Pulitzer-winning Holocaust historian Saul Friedländer reassesses those letters and diaries, emphasizing “the personal anguish” that informed Kafka’s singular canon. Friedländer’s concise new book, born of both sorrow and affection, is an ideal place to begin among the hulking alps of Kafka studies. In a touching introduction Friedländer outlines the parallels between Kafka’s life and his own, “all these hidden links” that give his delving into Kafka’s work a visceral pitch absent from much of the Kafka industry. With his attention to those lines in Kafka’s letters and diaries that were excised by Kafka’s friend and puritanical literary executor, Max Brod, Friedländer does a lovely service to the real Franz Kafka.

The autopsy of a writer’s personal papers is normally a tedious endeavor, but as Friedländer makes clear, Kafka’s diaries are evidence that he was incapable of a quotidian thought; his letters are astonishing documents with an intellectual and stylistic register to rival Keats’s. (As Brod put it in 1937: “He never spoke a meaningless word.”) His famous, almost fifty-page “Letter to His Father” is an incomparably naked confession of familial truth, a cathartic eruption written just four years before Kafka’s death. Any son with volcanic feelings for his father cannot fail to be awe-smacked by this letter—a letter that never reached its target because Kafka’s mother, ever protective of Hermann Kafka’s frangible sense of self, never delivered it.