As far as schools go, there was nothing remarkable about Tuol Sleng. The building stood unobtrusively along an avenue in Phnom Penh. But it was in its ordinariness, in the way it became part of Cambodia’s urban landscape, by not drawing any attention, that the school gave meaning to Hannah Arendt’s chilling phrase, the banality of evil.

Tuol Sleng had, at one time, been the torture chamber of the Khmer Rouge, whose murderous rule lasted from 1975 to 1979 in Cambodia. In July, an officer of the Khmer Rouge known as Duch was sentenced after the tribunal adjudicating war crimes committed in Cambodia found him guilty for his pitiless reign over that building. That sentencing won’t offer salve to the wounds of any of the thousands of victims who had been in the jail. But its intent was to offer a sense of closure, or completeness, to those who were jailed, beaten, tortured, and killed for crimes they didn’t commit.

The rooms inside were filled with ordinary objects—a bed made of iron, on which victims were tied and their arms and legs stretched to inflict maximum pain. The beds were rusted. There were dark blotches on the wall. I didn’t need a guide to tell me it was blood—and not one person’s blood, but of many, mingled together in pain, splattered on the wall, frozen in time. There were other tools—some used to dig, some used to cut, some used to sharpen, a few to drill walls, some to push nails through walls. But none had been used for those intended purposes; each had been used instead to savage human bodies, to cause wounds, to puncture skin, to let blood pour out.

To avoid that, people were willing to admit to anything. I read confessions, written in crooked, shaky handwriting, by young men, many of them foreigners, saying they had plotted to overthrow the government. The sheets on which the confessions were written had faded, as had the ink, but the desperation was apparent—the unsteady hand suggested how the people were willing to confess to whatever the man with the iron chain demanded, if only to stop the beatings. But the pain only ended with their death.

Haunted memories: Cambodia’s Tuol Sleng facility is a museum to the victims of Khmer Rouge’s brutalities . Bjørn Christian Tørrissen/Wikimedia

In the hall before I left the school, now turned into a museum commemorating the Khmer Rouge atrocities, was a large map of Cambodia on the wall, made entirely of skulls. I left speechless, which was the intended effect. Words were not necessary; silence—out of respect for those who died, and out of the sense of horror over those responsible—was the only response.

Many years later in Berlin, as I walked through another memorial built to mark another colossal atrocity—the Holocaust, at the Jewish Museum—I experienced something similar: the silence that cries out for some sound of love or hope. The museum in Berlin had stark lines and tilted walls. There were large pillars that rose and fell. As their height reduced, the ground beneath your feet seemed to rise, making you feel as though you were sinking in a tunnel that was getting narrower, squeezing you. But just as you adjusted to that level, it would change again, altering the topography, confusing you about where the ground lay, where the sky reached, and where you stood, within that space.

Disorientation is a complex idea—it is not easy to describe it; but most of us have felt it sometime. What that spatial experiment achieved was what no photograph, no testimony could: It disturbed your sense of certainty, of your moral universe. This was Germany, the land of philosophers such as Kant and Schopenhauer, and authors such as Goethe, Mann and Schiller, the home of abstract ideas. But also the land which, driven by an insane, messianic zeal, devoured millions of lives. That space symbolized the lives cut short, and how that destabilized the moral universe, as if you were alone aboard a ship tossing in waves.

What happens after such a ghastly experience? A tragedy on such a scale evokes mixed responses. Some seek justice, failing which they want revenge. Some find the adequacy of justice itself insufficient, and want to plunge back into violence. Forgiveness can heal, but before the survivors can forgive, those who committed those evil deeds have to express remorse. Many find it hard; they return to pointing fingers—you did it first.

There, the Apartheid Museum in Johannesburg shines: It forces you, almost by design, to be what you are not, and experience history through the lives of others. The ticket assigns you an identity—you are white. Or non-white. You are suddenly separated from those who came with you. And you discover the world through eyes not your own.

Understanding the horrors of the past century is not easy. But reality is different when you look at those horrors not as a film on a giant screen, but through a different pair of eyes, of the person struggling to emerge out of the stamped boot. It explains why people seek justice. And it brings us closer to the meaning of remorse and forgiveness.

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