The root of the word catastrophe is Greek, katastréphō, and means to overturn. Ten years ago, on December 26, 2004, in the Indonesian province of Aceh, the Indian Ocean tsunami brought tens of thousands of people to their deaths, with waves so wild and vast they seemed to overturn the sea.

I was at home in Indonesia’s capital, Jakarta, when images of bodies and debris began to appear on television. They were shown in slow, fragmented loops, like dreams. In layers they gathered force. On screen, people’s bodies clogged up rivers, their limbs and heads bulbous like rag dolls. My mother asked how anyone could celebrate the new year with death so close.

The images disturbed me. When I learned that a friend of mine, Monica Tanuhandaru, was in Aceh working on the relief effort with the Indonesian government, I joined her.

In Aceh, I met a man who suffered terrible nightmares. Nek Beng and his wife lived in the ruins of the only house to survive the waves in Calang, a town down Aceh’s west coast. Their neighborhood was once a lively town center of about a thousand people, but I was told that only seventeen had survived. In colonial times, Dutch merchants drove through the streets smoking cigars, and later, when Nek Beng was growing up, the town was full of traders, fishermen, and thieves from Java and other parts of Sumatra.

When I visited, nothing of the original town was left but rubble and asbestos. Mounds of earth dotted a field nearby. They were burial sites, some the size of children, marked with white pebbles and faded scraps of cloth on sticks. Dry grass blew silently among the graves. And yet, life persisted. Disaster agencies had put up tents and wooden shacks, and tsunami survivors from elsewhere had moved in. The front part of Nek Beng’s house had been turned into a restaurant. Every evening it was full of people laughing and smoking cigarettes. Curries were piled up in large bowls by the window, and people sat eating noodles and gossiping under a bright electric light.

I wanted to know more about this—about life returning when the waters had scarcely retreated—and went to visit one afternoon with a student from the local university. The restaurant was closed, so we picked our way round to the back. Inside, a large set of stairs led up to the second floor. The banisters had been destroyed, leaving only rough cement steps; above them, a light bulb swayed from a wire. The waves had punched large holes in the walls, through which I could see palm trees and blue tarpaulin.

Nek Beng shuffled downstairs wearing sandals and a checked sarong. He told us that on the day of the tsunami, he had been up in the hills. “I ran up the mountain when I saw the sea rise, and so I was saved,” he said. For days afterward, he lived in the hills with other survivors, eating bananas and drinking coconut water.

When he returned, he found his hometown flattened. For two weeks, Nek Beng wandered about, searching for his wife and children. But he found no one. Dead bodies that had been discarded by the sea covered the ground. They were soft and swollen, and stank. It was hard to recognize people. When the human heart stops beating, the body is seized with rigor mortis, and then begins to bloat. The skin becomes black; the body putrefies. When the nose decays, it leaves a hole.

Later, Nek Beng learned that his wife and son were alive, but that his daughters and four of his seven grandchildren were dead. None of the rest of his extended family had survived. “No one,” he said. “All ninety-six of them died.”

He showed me a small, faded photo album. In it, under cracked plastic sleeves, were photographs of his daughters, Zuriyah and Darmawati. They posed on motorbikes and in front of buildings. Zuriyah, his eldest daughter, had been a nurse. She was a kind, devout girl, he told me—more devout, in fact, than the rest of the family. She and her husband had been members of Jamaah Tabligh, the pacifist Islamic spiritualist group. By the age of thirty-three, she’d had five children, two of whom survived the waves.

Nek Beng traced his finger along the album. “I dream of my daughter at night,” he told me. “It keeps me awake. It is almost as if she is alive.” He rubbed his eyes, which were milky and tired. “She asks me to raise her children.”

When I left, he gave me his address. “Nek Beng,” he wrote in small, careful script in my notebook. “Desa Bahagia, Calang.”

Desa Bahagia means “Happy Village.”

Calang sits on a low, hot peninsula about sixty miles from Banda Aceh, the capital of Aceh province. The towns are connected by a coastal road, which snakes its way over muddy rivers and limestone cliffs that drop into the sea. Before the tsunami, the trip from the provincial capital to Calang took four or five hours by car. But a year after the disaster, the road was still in ruins, so the only way in was by helicopter or boat.

At the time, the town was not much to look at. There were clusters of newly built houses with zinc roofs, a network of dirt roads, and a smattering of wooden shacks covered in tarpaulin. But the setting was spectacular. The peaks of the Gayo Highlands rose abruptly in the distance, and the earth, rich and volcanic, sprouted banana trees and coconut palms. Seen from the air, the ground was a mass of inky green. Yet on patches of the coast nearby, the tsunami had left the landscape looking strange and prehistoric. Dark pools of water lay stagnant behind the beaches. In a field outside town, wizened, leafless trees with ashen bark stood twisted in contorted forms. Nearby, on a large rock by the sea, someone had painted “Hollywood” in bold white letters.

The water was alive, and sped toward land at the speed of 450 miles an hour. It was hot, and sounded like thunder.

Before the tsunami, Calang had been a busy town of about 8,000 people, the capital of the district Aceh Jaya—“Glorious Aceh.” It had schools, mosques, and a busy marketplace. At one end of town was a Dutch cemetery with white and gray tombstones. Toward the other, past the telecommunications tower, was the district regent’s office, a two-story building overlooking the sea.

At 7:58 on the morning of the tsunami, about a hundred miles from Calang, where the India and Burma tectonic plates meet deep in the Indian Ocean, the seabed began to rupture. The earthquake, which lasted four minutes and measured 9.0 on the Richter scale, caused one plate to jam up violently over the other, dislodging billions of tons of water. It unleashed the energy of 23,000 Hiroshima bombs. The water was alive, and sped toward land at the speed of 450 miles an hour. It was hot, and sounded like thunder.

When the wave approached land, the swell sucked the ocean out by hundreds of meters, leaving fish floundering on the exposed seabed. Then it rushed in, obliterating everything in its path. It was not the gargantuan arc of mythical tsunami drawings. Instead, the seawater was like a rolling tide, one that uprooted cars, buildings, and trees in its wake. Someone described the force of the impact to me this way: Imagine you are driving, and flies hit your windscreen. Now imagine those flies are trees.

Aceh, closest to the epicenter, was hit first. The waves then struck the coasts of Malaysia, Thailand, Sri Lanka, India, and the Maldives. They rolled outward with brutal rhythm, ravaging the coastline of the Andaman and Nicobar Islands and reaching as far as the Horn of Africa. By the time they subsided, more than 227,000 people had been killed. More than two-thirds of the dead were in Aceh.

Calang, the only town on its promontory, was hit from all sides. The water crashed over the Dutch tombstones into the heart of town, wrecking the district regent’s office and reducing the telecommunications tower to a twisted heap of metal. And it wiped out the population. When the waves receded, three in five people were dead.

I was twenty-eight when this happened, and knew little of death or grief. A friend of mine had died, years before, but that was a smaller, personal thing. Grief of the kind faced by people in Aceh, a loss that seeped into everything, was unknown territory to me, and nothing I had seen then—or in the years since—could have helped me understand its enormity.

At first, the sorrow around me was hidden behind the hustle of the everyday. Monica and I worked for the Indonesian minister in charge of the relief effort. We lived and worked out of the pendopo, the old Dutch governor’s residence, which had been turned into the headquarters of the emergency response. There, in the large hall hung with chandeliers and furnished with shellacked, ornately carved wooden chairs, starting at 6 a.m. each day and ending at midnight, the minister held meetings to coordinate the relief effort. Every night, he met with the military, the national disaster agency, and officials from the UN; every day, he met with representatives of humanitarian organizations, religious groups, and businesses, and received journalists, politicians, celebrities, or visiting heads of state. On the grounds outside was a large tent, cluttered with plastic chairs and makeshift tables, jumbled with extension cords and cables, notice boards and maps. At all hours people flowed in and out. There were media briefings and delegations. Bill Clinton and George H. W. Bush came by to visit; charity agencies arrived in the dozens to deliver assistance; scientologists opened a booth offering massages to survivors. The sky was filled with helicopter staccato. A US aircraft carrier was deployed in waters off the coast.

Amid the chaos and the noise, there were photos. Faces stared from everywhere on white photocopied sheets of paper. These were tacked onto notice boards and walls, on doors and gates outside. Some had fallen to the ground; others fluttered on trees. Underneath the faces were phone numbers scrawled in pen. There were portraits of people alone or in pairs; students in graduation robes; mothers with their babies; wedding photos; snapshots taken at picnics and at the beach. But many were of large groups. These were usually formal and more somber portraits of families taken in studios, with fathers in suits and mothers in headscarves, high-backed and proud, sitting with their children, often in matching clothes, staring in anticipation of the photographer’s flash.

I knew these photos. Hung on the walls of my family home in Jakarta were photos like these, of my parents and my brother and sisters and me, wearing batiks and kebayas, arranged by height and staring stiffly at the camera. There were similar photos too in the long wooden houses in my mother’s village in West Sumatra.

On the photos in Aceh, sometimes almost all the faces were circled missing. In these pen strokes there was desperation. When I looked at the photos, I saw people’s eyes. All of those eyes, staring out, stopped in time.

“I’ve seen famines, wars, everything,” said a British journalist I knew, “and the tsunami was, by far, the worst thing I have ever seen.” The journalist was in Banda Aceh to find locations from which to film a tsunami one-year special for TV and had identified a plum spot opposite Baiturrahman, the city’s main mosque.

“But people here amaze me,” he continued. “I remember one guy who lost everything—his family, his house. Within a month, he had opened up a coffee stall. Why? He knew eventually there’d be construction—and construction workers need coffee. And that street outside the mosque, that narrow one—that was death street. And now it’s a market.”

In Aceh, loss appeared to be everywhere and nowhere. In public, people did not weep. They did not lament. Many of the humanitarian workers I knew commented on the “extraordinary resilience” of tsunami survivors, on how calm people seemed, on the almost eerie extent to which they simply got on with their lives. They said, with some guilt, that they sometimes forgot things were not normal, because on the outside people around them seemed to cope so well.

The landscape in Banda Aceh was split between normalcy and ruin. Below the high water line, the earth was a wasteland.

I had the same thought when I saw a friend of mine, Rina Meutia, whom for some days after the tsunami I had feared dead. “Oh, don’t worry about me,” she said breezily when I first saw her. “I am fine.” I later learned that she had been at home when the earthquake came, and had survived the waves only by running with her family into a mosque.

The landscape in Banda Aceh was split between normalcy and ruin. Below the high water line, the earth was a wasteland. The landscape in the tsunami zone was low, with rubble piled only a few feet high, so that when I walked around it, and saw a motorbike perched atop the bricks, it looked garish and outsized against the sky. In the ruins of one of the houses, I saw a blue squat toilet, shiny and intact. In its brightness, it seemed naked and exposed.

People had died too, in this way, with the water ripping off their clothes, exposing their nakedness to the sun.

Above the high water mark, all was as before. In the untouched parts of town it was even possible to imagine that the tsunami had never happened. The gallows humor of survivors reflected this. One morning, about a year after the tsunami, Ben, an employee of the guesthouse I had moved into, gave me a ride to town on his motorbike. The previous day, he had shown me portraits from his wallet of his dead wife and children. That morning a friend of his drove up beside us. “Who’s this on the back of your bike?” he cackled, poking Ben in the ribs. “Your wife was killed in the tsunami, so now you’ve got yourself another one!”

In a famous, though contested, study from the 1960s, “The Rope of God,” anthropologist James Siegel notes that in Acehnese culture the ability to control one’s grief is not just desirable, it is a sacred duty, part of the essence of being human. For the Acehnese, he writes, man is distinguished from the animals because he possesses not just hawa nafsu (all things instinctive, such as hunger and desire), but also akal (rationality). Overcoming hawa nafsu through akal is what religion is all about: it is what makes one a fully realized person. He tells the story of Sjarifah and Abdullah, two parents whose son has died. Abdullah is able to control himself. “Whenever Abdullah felt himself about to surrender to the grief that arose within him, he prayed or read the Koran,” Siegel writes. But Sjarifah is unable to control her grief and mourns openly. This “was not considered a normal reaction,” he comments. “She was not supposed to grieve.”

No one I met in Aceh ever mentioned akal, hawa nafsu, or, for that matter, James Siegel to me. The book was about the past and other people. It seemed to have nothing to do with my friend Rina, whom I could not picture as an object of study, but saw simply as my friend: a person I loved and who had lived something. But some of what Siegel said rang true. He found what he saw jarring, or, at least, worthy of study; visitors to Aceh found what they saw “amazing” and unexpected.

I did not know how to comprehend what I saw. And most of the time, I did not know what to say. When people told me their families were dead, I said sorry, which felt feeble, but I had no other words. I did not know what to say to my friend Rina, whose family survived, but who lost others she cared about, and who, after the seawaters engulfed her piano, lost her music. Mostly we drank coffee and discussed Internet connections and lack of sleep, and laughed at the absurdities of humanitarian relief, a world where people might send ski jackets to a disaster zone in the tropics. When she said she was fine, I did not probe too much. But then I wondered if I was failing her in friendship, and failing to understand.

It was as if each person’s grief took the measure of itself and shrank to fit the space left over by the sorrow of others.

In her book Upheavals of Thought, the philosopher Martha Nussbaum argues that emotion is bound up with intelligence: it is not opposed to rationality but rather at its center. Feelings such as love and sorrow are finely tuned responses to judgments about what is true and valuable in the world. As such, our beliefs about the outer world can condition the experience of the inner: they affect not only the way we behave, but how we feel. If I believe in God and an afterlife, for example, I might feel grief differently from someone who does not. The name we give our emotion will be the same, but my grief may contain some hope.

I wondered if this might be true too about grief in the face of catastrophe. Was it that in the face of social expectation people in Aceh sought to overcome emotion and control how they behaved? Or did catastrophe overturn something about the emotion itself? I wondered if the vast weight of the tsunami made small the space for grieving. It was as if each person’s grief took the measure of itself and shrank to fit the space left over by the sorrow of others. And so the human spirit flourished instead, and in this there lived a kind of beauty.

Or perhaps I was simply deceiving myself, and it was not the size of grief that shrunk but my seeing of it. To imagine people were resilient was an easy way out, a way of finding strength and good in something whose scale of devastation and indifference was otherwise incomprehensible. Perhaps the simplest explanation for the way people seemed was post-disaster trauma and shock.

The truth was that I could not know. It was probably a combination of all of these things, or none of them, or something I had not thought of. The catastrophe destroyed houses, land records, personal items, photos, and everything else that might be important. It meant that everyone had to overcome grief, but no one’s grief was special. And who was I to understand this? I did not know how to begin.

Most people I met in Aceh told me the tsunami had come as judgment from God. The waves themselves had shown this.

“The water was churning,” one man in Calang, Nurdin, told me. He had watched the tsunami from the mountains above Calang. “At the top of the wave, it was like there was smoke. The waves came all the way from the middle of the sea. The first destroyed the buildings. The second killed the people. But the third was the biggest. I felt doomsday had come.”

His neighbor, Jasmaniar, told me that people in Aceh had been materialistic in the years before the waves and had begun to lose sight of who they were. It was not that they had not suffered. They lived through years of separatist war with the central government, years when soldiers took men away in the middle of the night, and in darkness only dogs roamed the streets. The war was still running when the waves hit.

In the highlands around Calang, I passed through villages where only shells of burned-out houses remained, and where white sun shone through the mist, and pampas grass grew through windows. People in Aceh were crushed by conflict before they ever saw disaster.

But still, people had begun to lose their path, said Jasmaniar. The disaster was a kind of judgment.

Along the entire western coastline of Aceh, mosques were often the only buildings left standing. Their domes rose high above the rubble, the only vertical structures for hundreds of meters around. To me, the explanation was simple: the architecture of a mosque, with a dome and open sides, provides strength, but enables water to flow through. But more commonly the explanation proffered was God. Flattened bricks, with a mosque soaring above them: people took this as evidence of the power of the Almighty. It was God, and the world of spirits, that shaped how people began to heal.

A few days after meeting Nek Beng, I went with a friend to Mon Mata, a village on the outskirts of Calang. The tsunami had left it a wasteland of debris and saltwater, but when we visited it was dotted with Oxfam wells, Islamic Relief shelters, and tents from the UN High Commission for Refugees. Behind their tents, most residents had built makeshift kitchens out of wood and plastic sheeting. Some had built their own houses with salvaged wood and scrap metal. On the road, Red Cross and Red Crescent trucks trundled past, high above the ground, with white canvas stretched over their frames.

That month, the village was busy with fasting and Ramadan piety. Each night, after breaking fast, groups of men with prayer mats slung over their shoulders ambled up to the meunasah, the local prayer house, followed by women in white prayer robes who tucked their sarongs around their ankles to prevent them from getting muddy.

When we arrived, a widow named Khairul Nisa invited us to stay with her. She slept in a white standard-issue UNHCR tent that she shared with her daughter. Inside, the tent was divided in two. Khairul Nisa slept on the floor in the back, next to sacks of rice on a wooden pallet and a plastic box for her clothes and bed sheets. The front of the tent, for visitors, was bare except for a roll-up mat and a hanger for her headscarves. On the wall, she had listed the names of her surviving family members, scrawled in tiny, scratchy capitals.

Khairul Nisa introduced us to her son-in-law, Yusran, a clean-shaven, wiry 39-year-old man who taught physical education to junior high school students. He wore a green and black nylon tracksuit and smoked heavily. We sat talking on his front porch after dinner while he flicked ash from his cigarettes into the candle. While we spoke, he occasionally fell silent, stared at me, and laughed slowly to himself. He did this when speaking about the power of religion against the supernatural—“I could show you if you were strong enough,” he said, over and over again—but its effect was to make it seem as if he might be playing an enormous joke.

That night a girl shuffled in carrying some washing. Yusran pointed to her. “That is Ani,” he said. “After the tsunami, her body was taken over by spirits. She became weak and stiff for months, and spoke with a dead girl’s voice.” He rolled his eyes back into his head and mimed rigor mortis.

“The voice was her best friend I’in’s,” he continued. “I’in died in the tsunami but her parents never found her body, and wouldn’t give her a proper burial. So I’in’s spirit entered Ani. She told us she was dead, and that her body was stuck in some rubble. She wanted her parents to accept her death, and to pray to protect her soul.”

Yusran told us that the souls of students in his school were troubled. They were quick to get angry, and were lazy and didn’t learn. Some of them had stopped going to school. The only thing that helped the students control themselves in public was religion. “There are different kinds of recovery,” he said. “There is mental, physical, emotional. We try to give them spirit with religion and exercise, so that they can recover more easily.” He told me that quite a few students had been taken over by the spirits of dead people, mainly of close friends and relatives. Mostly, though, the students just had gangguan jiwa: they had their souls encumbered. The spirits disturbed them.

When I asked him to elaborate, he told me that in fact it wasn’t dead people’s souls that had entered, but djinn. In Islam these are spirits, born of flame, who can possess people, what I have seen described as the “spirits that live alongside people.”

When I was first in Aceh, I didn’t think much about ghosts. We slept on the floor in a side room in the pendopo, surrounded by laptops perched on cardboard boxes, drinking out of plastic water bottles and eating instant noodles. The pendopo was a beautiful Dutch building constructed in the days of empire and decorated with sepia photographs of governors past. After the tsunami, its verandah was used as a place on which to pile bodies, one on top of the other.

Feeling fear would have been to deprive the dead of dignity.

We slept in the room behind that verandah. If I had been at home, and knew that a body had lain outside my room for days, glazed with the startled shrunkenness of death, I would not have been able to sleep. But in Aceh I was not afraid. This would have been to see them as monsters, somehow malevolent and outside the realm of the human. Feeling fear would have been to deprive the dead of dignity.

One night as I was sleeping, I heard rattling and dogs howling outside. I felt hands pressing down on my chest. I dreamed I was in a car and someone was trying to touch me and wouldn’t let go. When I awoke no one was there.

Later, I thought more about ghosts—not about the spirits of the dead, but the spirits of the living, their memories and imagined futures. Nek Beng had told me that he never found the bodies of his daughters and grandchildren. He’d told me that he couldn’t look at burials on TV anymore, because if he saw one, he started crying and couldn’t stop. Eid was coming up, and he and his wife had nowhere to go. “What is there to hope for now?” he’d asked me.

Before I left Aceh, I went to see the head imam of Baiturrahman, the grand mosque of Banda Aceh. The mosque was built by the Dutch in 1879 to replace the destroyed Grand Mosque, which was originally built during the reign of the seventeenth-century Acehnese ruler Sultan Iskandar Muda, the “Young Alexander.” It is white, with sweeping black domes. At its entrance, I recognized a man who, in January, had hung around the airport selling maps to aid workers. He now sold postcards from a wooden bench. I flicked through his selection. There were postcards of the mosque, and several of bloated corpses clogging up the river.

People told me that during the tsunami a hundred bodies were washed into the gardens of the mosque. But the mosque itself was spared. The waters only reached the top of the steps, so the people who ran inside to seek shelter were saved. That had added to the mosque’s mystique. I heard many stories of people inside the grounds being lifted up and saved. People said they had seen angels.

I went inside. The head imam, Dr Teungku Haji Azman Ismail, had a modest office around the back on the second floor. Outside his office, there was a large room with several desks and a small waiting area for guests. It looked like an administrative office in a district civil service, except for a noticeboard on the wall with a list of upcoming weddings.

The imam welcomed me. He looked tired. “We try to help people with their problems,” he said. “We use this mosque as a center for counseling people.” The mosque had its own radio station, Radio Baiturrahman, and, although the equipment was destroyed in the tsunami, the imam had met with Indonesia’s vice president, Jusuf Kalla, who’d helped them to restore it.

“We used that radio to give counseling,” he said. “We invited different ulama to preach about the tsunami every night in February, and broadcast it on the radio between evening prayers and morning prayers. I hope people were able to find solace from it.”

He leaned back in his chair. “Before the tsunami, people thought human beings could conquer the environment,” he said. “In the past, our rice fields had to wait for the sun and rain. Then we discovered irrigation. People used to think we were bigger than nature. Now we know we are not.”