The original publication of Gunter Grass' "Peeling the Onion" in Europe in 2006 created a firestorm in the international literary community. At issue was not so much the revelation that the Nobel Prize-winning author of more than two dozen works -- including "The Tin Drum" and "The Flounder" -- had served in the Waffen SS while a young man, a fact for which he offers a convincing circumstantial explanation. More puzzling, and for some unforgivable, is the fact that he waited until now to come clean and that he occupied for long decades a moral pulpit to which he was not entitled. Responses ranged from bitter excoriation from some to near exoneration from others, notably Grass' fellow Nobelist and moral spokesperson Nadine Gordimer.

Tempting as it is to take a deep breath and wade back into the debate here, it seems more useful to ask the interested reader to Google the controversy and to consider the memoir as the intriguing and wide-ranging literary document that it is. The issue is, on the author's own admission, not just laid to rest or sequestered from any other developments of his life, which he tracks from his early childhood to his postwar embrace of his literary vocation.

Grass' title is also the book's logic, the structural metaphysics of his self-accounting, for though he hews to a basic chronology in his narration, the procedure is complicated and enriched at every turn by his persevering effort to unpeel the layers of the life-onion, a process yielding ever deeper inquiries into emotional and character formation -- and often enough bringing him to tears. "But what do I see," asks Grass at one point, "when I hold up the lone tank gunner by half-moonlight and view him as an early edition of the man to come? He looks like a character who has escaped from a Grimm's fairy tale. He is about to cry. He clearly doesn't like the story in which he appears."

At heart, Grass is a robust maximalist, a metaphor-spinner to whom little that is human is alien. He does not linger long with handkerchief pressed to his face -- he has a rich, ruminative and ribald tale to tell.

He writes first of his boyhood years in Danzig, the Baltic port city that was largely destroyed during the war, to emerge later rechristened as Gdansk; of his constricted family horizons and the first expansion of those horizons by way of collecting the reproductions of masterpiece paintings that came with cigarette packs (if literature proved to be his major, then art was, through his early years, a strong minor). First, though, came the long and collectively traumatic digression of war: conscription into a labor force, chaotic years of military service, ragged sojourns through the ruined landscape of postwar Germany. Then his earlier obsession led him to become a stonemason's apprentice working mainly on gravestones and to studying sculpture. Only later did he begin the literary efforts that eventually unlocked the floodgates to the epoch-making prose of "The Tin Drum."

One of the many fascinations of "Peeling the Onion" is Grass' way of intercutting his narration with unobtrusive but illuminating asides, pointing out when it is relevant just how an event was later incorporated or transformed into literary expression.

At one point, he describes a dinner party scene: "... the family gathering round the table was still in full swing ... when a boy about three years of age, the son of my clear-sighted moviegoer friend's sister, entered the smoke-filled room with a toy drum hanging from his neck and struck the round sheet of tin with wooden sticks ... It was a scene that left its mark, a picture that stayed with me. But it would be a long time before the bolt slid open, the flood of images was released and with the images, words I had been saving since childhood."

We see not only the peeled back essence of the inner and outer, but also feel, throughout, the potency of the shaping imagination. Whether this is enough to fully exonerate the man who kept such long silence is a matter for his readers to decide, but I will attest that the gathering of evidence is rarely dull, is almost never without some higher artistic gratification. Grass comes through on every page as a man to whom it has been given to make powerful and controversial art.

(Sven Birkerts is the author, most recently, of "Reading Life: Books for the Ages." He edits the literary journal Agni at Boston University.)