BERLIN -- More than 16 years after the wall fell, West Berlin and East Berlin have melded together enough that a visitor wandering around the city often can't tell which was which. But at a dingy gray building surrounded by concrete walls topped with barbed wire, there is no escaping the creepy feel of communism. This was a prison run by the East German secret police, the Stasi, which has been preserved as a memorial to the crimes of the past.
Our guide today is a paternal figure with the learned air of a retired college professor. Hans-Eberhard Zahn, who taught psychology at the Free University of Berlin, learned a lot about the human psyche right here - as an inmate.
The Stasi was one of the most ambitious and systematic instruments of totalitarian rule ever devised. Adolf Hitler's dreaded Gestapo terrorized a nation of 65 million with just 15,000 agents. The East German version, by contrast, had 85,000 internal spies - and more than half a million informers - to monitor, harass and intimidate a people numbering just 17 million.
It compiled dossiers on one of every three men, women and children in East Germany. Citizens later granted access to their files were shocked to find they had been betrayed by neighbors, co-workers, priests, teachers, friends - even spouses and children. As Anna Funder writes in her new book, Stasiland, "Everyone suspected everyone else, and the mistrust this bred was the foundation of social existence."
Mr. Zahn was arrested while visiting a fellow Free University student in East Berlin, in the days before the Berlin Wall cut off access. Originally suspected of being an American spy, he eventually was sentenced to seven years behind bars because of some articles he had written for a student publication that allegedly "endangered the peace of Germany and the whole world."
He explains how the Soviets, who first ran the installation after World War II, would torture inmates. Over here is a space about 5 feet high and a foot deep, where prisoners were enclosed for up to 72 hours. Over there is a cell that could be filled with 10 inches of water, so the occupant could not sit down.
But once the East Germans took over, they used a different approach. Mr. Zahn escorts a small group to the cell he occupied for 10 months in 1953 and 1954. It measures about 6 feet by 10 feet, and its only furnishings are a bucket and a wooden bed with no mattress.
It's not the Four Seasons, but he was never physically abused, much less tortured. He got plenty to eat, and the cell was well-heated in winter. "If I had a headache," he says, "I got a tablet."
The pressure was of a different kind: "There was nothing to read, nothing to write, no one to talk to." The light stayed on at all times. No prisoner was ever allowed to catch a glimpse of another prisoner.
He would sit in his windowless cell, behind a door whose peephole could be opened only from the outside, allowing guards to watch him unseen. "You were entirely alone but also permanently under observation," he explains.
The crushing isolation affected his mind in strange ways. He found himself yearning to be interrogated by his captors, or even beaten. Any interaction seemed better than none. When he was first questioned, Mr. Zahn broke into tears of gratitude at being addressed by name.
Treated with outward kindness by the officer in charge, "I thought, `This is my friend.' I regretted that I couldn't tell him what he wanted to hear."
At the end of the tour, an Australian visitor asks an obvious question: Does Mr. Zahn see a parallel between the prison and the U.S. detention center in Cuba? "No," he says firmly. "The inmates at Guantanamo Bay are very different from those here. We were not even suspected of being terrorists."
Still, it's hard to imagine any American visiting here without feeling that the similarities are too close for comfort. But what is most striking about the Stasi facility is that it was not an overreaction to a clear danger. It was a microcosm of an entire system that made paranoia about its people the central governing principle. Even East Germans who never saw the inside of this prison knew what it was like to live as an inmate: always alone, always under surveillance and always captive.
Steve Chapman is a columnist for the Chicago Tribune. His column appears Mondays and Wednesdays in The Sun. His e-mail is firstname.lastname@example.org.