The birds are singing outside; a warm, spring wind is gently drifting into the living room from the garden. An old man -- tall and powerful-looking with white hair and blue eyes -- sits in an armchair next to a fireplace. Three carved angels displayed on the mantel.

The man rests his right leg on a stool. He is very calm and speaks quietly -- and tells the story of the man he once was.

"A new shipment had arrived. I had been assigned to ramp duty, and it was my job to guard the luggage. The Jews had already been taken away. The ground in front of me was littered with junk, left-over belongings. Suddenly I heard a baby crying. The child was lying on the ramp, wrapped in rags. A mother had left it behind, perhaps because she knew that women with infants were sent to the gas chambers immediately. I saw another SS soldier grab the baby by the legs. The crying had bothered him. He smashed the baby's head against the iron side of a truck until it was silent."

The man looks out of the living room window, almost entirely motionless. His thumb swings back and forth over the edge of the chair like a metronome. Outside, the sun shines on neat rows of brick houses surrounded by carefully tended, weed-free gardens. Oskar Gröning lives in a well-ordered world.

He unbuttons and rolls up his left sleeve. "Here," he says, "look at this."

There is a tiny blue dot above his elbows, the remainder of a tattoo. "It was poorly executed," he says. It was supposed to be a zero, representing blood type O. Everyone in Auschwitz was tattooed, prisoners and guards alike. Jews were tattooed with their inmate number and SS guards with their blood type. Oskar Gröning was a member of the SS in Auschwitz for two years.

His dreams often end in screams. The screams turn into thunder, the thunder into humming and the humming into silence. They are the sounds of death from the gas chambers.

An organized world amid terror

Gröning, though, didn't kill anyone. He didn't pour Zyklon B into the shafts or burn the piles of dead. He watched. He stood there, shocked at first, then indifferent. It became a routine.

He lived in an organized world and its order ensured that the terror of the concentration camps could be compartmentalized, kept apart from the foundations of civilization. The terror was subject to clear command structures and tightly regulated service schedules, assignments of duties and positions, making one man a torturer and another a bookkeeper.

Gröning was a bookkeeper, and a conscientious one. He counted the Jews' money, sorted it and locked it into a safe. He was a bookkeeper of terror.

There is a photo album on the coffee table -- Gröning's life in pictures. Two-thirds of the photos are in black-and-white, the last third in color. But the pictures are unrevealing. Gröning just wants to talk, for hours, days, "it doesn't matter how long," he says, "talking helps."

Oskar Gröning, born in 1921, is one of the few members of the SS still alive today. His history, a German history, is a story of seduction and fanaticism, of perpetrators and their accomplices, of living with guilt, and of the search for other concepts of guilt. It is the story of a man's attempt to overcome a past so dark that it can never end.

He opens the album, the thin sheets of vellum between the pages rustle, and he leafs through family photos of his father, grandmother, grandfather, Aunt Marie, pictures of baby carriages and bike rides, until he reaches the images of men in uniform. His father was a member of "Stahlhelm" (Steel Helmet), a paramilitary group of German nationalists who fought against the Treaty of Versailles, against demands for World War I war reparations, and later against the Weimar republic between the two wars and against democracy.

"Father performed in nationalist plays in assembly halls behind local bars," says Gröning. In one play, a German was shot by Frenchmen because he resisted France' post-war occupation of Germany's industrial Ruhr region. "Discipline, obedience, authority -- that was how we were raised," says Gröning. His mother died when he was four.

The Jews were the "pig merchants"

He continues leafing through the album, clearly searching for something. "Here," he taps a photo with his finger, "look at the way we used to march."

The picture, taken in 1933, shows a group of children wearing military uniform, marching behind a flag. A flag displaying a swastika hangs from a house. Young Oskar, marching in the first row, is twelve years old and a member of the youth wing of "Stahlhelm."

Was did the uniform mean to you?

"It fascinated me. Even today, when I hear military music," his voices trembles and breaks. "Forgive me, but it's such an experience for me, so uplifting, even today."

Next to his father's house was an iron goods shop owned by a Jew named Selig. He had a daughter, Anne, and the two children used to play marbles on the street. One day men from the SA were standing in front of the shop, holding up a sign that read: "Germans, do not buy from Jews." After that, Gröning and Anne began playing in the courtyard, instead of the street.

What were you thinking when the men from the SA held up the sign?

"Nothing, nothing at all," says Gröning. His voice is quiet and firm once again.

A door opens and his wife places a tray of cake on the table. The tray is covered with plastic wrap. "For later," she says. Then she leaves the house. She prefers not to listen.

He waits until his wife has closed the front door behind her. Then he says: "You see, for us the Jews were the pig merchants, the lawyers who always had a shady reputation when it came to money. People used to say: The Jews are taking the Christians for a ride. It's just their way."

Did Anne Selig's father take advantage of people?

"I didn't think so at the time."

Oskar Gröning removes his leg from the footstool, sits up straight and begins to sing, quietly at first, then louder. "And when Jewish blood begins to drip from our knives, things will be good again."

"My honor is loyalty"

The distinctions between the man of today and the man of the past blur for a moment, but then he returns to the present and says: "Back then we didn't even think about what we were singing."

He continues leafing through the album. He has written "1941, with Aunt Anna" in blue ink beneath a photo with jagged edges. It depicts the young Gröning, tall, blonde and wearing a uniform with the letters SS stitched into the collar. He sits on the arm of a chair and smiles, obviously very proud of his uniform.

He had seen images of the SS in weekly news reports. He thought they were smart, the smartest unit of all. He volunteered in 1940.

Why?

"It was spontaneous enthusiasm, a sense of not wanting to be the last one in the game, when the whole thing was practically over."

For two years, Gröning worked in a paymaster's office. In October 1942, he received new orders. A senior officer told him that he had been assigned to a special task, one that was of great importance for the German people, for Germany's ultimate victory. He was told that he should think of his oath, of the words inscribed on his sash. "My honor is loyalty." And, finally, he was told that he could never reveal the nature of his new assignment to anyone, for as long as he lived.

A clock in the living room chimes. It's six o'clock, and Oskar Gröning has been talking for the past five hours. He has eaten cake and continued talking. At this point in his story, the young Gröning has arrived in Auschwitz. Perhaps the elderly Gröning would like to take a break?

"No, no, it doesn't bother me at all," he says. He fetches a bottle of mineral water from the kitchen. His wife hasn't returned yet.

Gröning is 21 when he arrives in Auschwitz on an October day. He gets there on a train from Kattowice, and is taken to his quarters in the administrative barracks. Others, who have been there longer, begin laying out their dinner on the table: sardines and ham, vodka and rum.

The SS is comfortable in this camp. But there must be something special about it, Gröning thinks. They drink a lot. Then, the door opens and someone announces that a new transport has arrived. Three men jump up, tie on their sashes and take their pistols along.

Counting the money of the dead.

Gröning wants to know what this means. Someone says: "Jews have arrived, and they are now being admitted to the camp. If they're lucky, that is."

"What does that mean?" asks Gröning.

"It means that some of them will be exterminated," says another man.

Gröning is taken to an office the next morning where he informs the superior officer their that he has been trained in banking. He is assigned to "Inmate Money Administration." An aide instructs him on his new duties and informs him that the Jews are required to surrender their money when they arrive in the camp. It is placed into a wooden box, and Gröning's job will be to sort it and, from time to time, deliver it to the main administrative office for Berlin.

He also learns that most Jews are sent to the gas chambers. The next day, Oskar Gröning begins counting money.

He believes in Adolf Hitler and Joseph Goebbels. He believes that it is the Germans' duty to destroy global Judaism. He believes that Germany lost World War I because of the Jews. And he wants Germany to win this war.

He eats well, works diligently and sleeps well. The men in the SS sleep in comfortable beds covered with soft, checkered quilts. They once belonged to the Jews.

After two months in the camp, Gröning is given an additional task. More and more trains are now arriving at the ramp, and someone has to stand guard to make sure none of the luggage is stolen. It is on the first day of his new assignment that he witnesses the baby's head being smashed into the truck.

He lies in bed at night, unable to sleep. You've gotten yourself into a vile situation, he thinks. He draws a line between individual excesses and mass murder committed by the society as a whole. He believes the excesses are barbaric, but the mass murder legitimate.

He goes to his commanding officer and says: "If this is always the way things are done here, I would like to be transferred." The officer replies: "What you saw the other day certainly was out of the ordinary. But you signed a letter of commitment. Everyone serves where he is assigned."

Sorting the money of the dead

Gröning returns to the order of terror. He is promoted from troop leader to deputy company leader. He guards the ramp when he is assigned there, and he counts the money when the wooden boxes arrive. He calls it "money without owners." He sorts Polish Zlotys, Greek Drachma, French Francs, Dutch Guilders, Italian Lira -- the plundering of a global community.

In the evening, when he has completed his duties, Gröning takes his dinner to the barracks, plays cards and games with his comrades and with his commanding officer. Sometimes his comrades are drunk by the time they are ready for bed and they use their pistols to shoot out the light. Gröning gets together with his exercise group on weekends, and they play games not far from the ramp and the gas chamber. They have a lot of fun together.

One night he wakes up to the sound of whistles. Jews have broken out. He runs through the dark until he reaches a farm, where he sees corpses littering the ground. He watches as naked people are herded into the farmhouse and sees a senior officer shut the door, pull a gas mask over his head, open a can and pour the contents into a hatch. Then he hears screams. The screams turn into a thundering noise, the thundering becomes humming, and then it is quiet.

He returns to his barrack with another man. The other man says: I know a shortcut. Along the way, the other man tells Gröning what happens when corpses are burned on grates. They bodies straighten and the men's penises become erect, he says.

The shortcut takes the two men past a pyre where corpses are just being cremated. Gröning moves closer to see what happens when human beings burn.

He submits another transfer request, and then another. In September 1944, he is discharged to a field unit and fights against the Allies during the Ardennes offensive.

Evening has begun to cast shadows in Oskar Gröning's garden. He has told the story of his life in Auschwitz, soberly, as if narrating a documentary. He gets up to fetch more mineral water. "Go ahead, ask me questions."

A horrible but necessary thing

What did you think when you found out that Jews were being gassed in Auschwitz?

"That it was a tool of waging war. A war with advanced methods."

But you weren't in the war. You were in a factory where systematic murder was being committed.

"If you are convinced that the destruction of Judaism is necessary, then it no longer matters how the killing takes place. As early as 1939, Hitler said in speech that if the Jews were to force a new war on the Germans, it would mean the end of Judaism in Europe."

But there is a difference between cheering for Hitler as part of an anonymous crowd and working in a killing machine.

"Yes, there is a difference. But, unfortunately, it just happens to be the case that they took me, Oskar Gröning, to this camp where the things that everyone was cheering about were actually happening. And then, at some point you are there and the only thing left is the feeling: I am part of this necessary thing. A horrible thing -- but necessary."

What did you feel when the Jews were taken to the gas chamber?

"Nothing, I have to say. Because the horrific wasn't obvious. When you know that killing is going on, you also know that people are dying. The horrors only dawned on me when I heard the screams."

Would it be correct to say that you became accustomed to Auschwitz?

"I settled in over time. Or perhaps better put: I became a part of internal emigration. Part of living in Auschwitz was perfectly normal. There was a vegetable shop where you could also buy soup bones. It was like a small city. I had my unit, and gas chambers were irrelevant in that unit. There was one side of life in Auschwitz, and there was another, and the two were more or less separate."

It's 8:30 p.m. The front door opens, and his wife walks in. She asks whether she should make cheese sandwiches. She suggests that she could set out the sandwiches and go the neighbor's for a while.

When Gröning returned from a British POW camp in 1948, he said to her: "Girl, do both of us a favor: Don't ask." She still doesn't ask.

Gröning offers to continue the interview at a hotel. He wants to move forward. He wants to settle scores.

The next morning he says that he slept soundly. He took a sleeping pill. His wife has already left the house. There is a bottle of mineral water on the coffee table. The photo album is gone, replaced by documents, documents that could exonerate him. Something like Oskar Gröning's certificates of achievement.

A tiny element in the structure

One document bears the reference number VP-55b/9.44/Zö/IG. It is a letter from SS headquarters in Berlin confirming his transfer. "The aforementioned has volunteered to serve at the front," the document states.

The second document is a letter from the Duisburg district court. The letter states that Gröning is being summoned to testify as a witness against a member of the SS accused of having murdered inmates at Auschwitz.

Oskar Gröning has underlined six words in this letter with blue ink.

"Summoned to testify as a witness." Not as a defendant. He is innocent, at least under the law.

When Gröning returned from the P.O.W. camp, he lived with his father's in-laws. One day they were sitting at the table, eating dinner, when the father's mother-in-law said: "How do I know that I'm not sitting here with a murderer? Or with a potential murderer?"

He slammed his hand onto the table and said: "I am sitting here because I am not guilty. I was not a perpetrator, and in this respect I am an honorable human being."

Oskar Gröning the human being, a tiny element in the Auschwitz hierarchical structure. That was how he felt, and that is how he feels today. But few would agree with him.

On the previous evening, when Gröning was already asleep, a British documentary about the liberation of the concentration camps was broadcast on TV. The film did not distinguish between those who committed murder and those who counted the money of the murdered. It showed men in SS uniforms and mountains of corpses. Monsters and their victims.

"I don't watch that sort of thing. It doesn't bring me any further. I know what corpses look like," says Gröning. His voice is cool and absent. A tear gathers in his left eye.

The images tell a different story. They say he is guilty. The pictures Gröning presents are softer, less radical, not as clear. They say he is innocent.

Gröning must continue his life when he returns from the P.O.W. camp in 1948. He wishes to remain undisturbed.

Since then, he has never watched anything, listened to anything or read anything that would take him back to the camp. He doesn't know about the Auschwitz trial that began in 1963, a trial that introduced the young German democracy to the details of the extermination machine for the first time. "I don't know anything about that," he says.