Dr Wee Teck Young sits in a corner of a quiet cafe in Holland Village, mulling over mortality.
"I know I may die any time. I may not have another conversation with you," he says dispassionately.
Noticing the grimace on my face, he smiles and continues serenely: "It's not morbid. That's the reality. But it doesn't stop me from enjoying our conversation."
He is not being melodramatic. For more than a decade, the 48-year- old's chosen home has been Afghanistan, a country ravaged by an international conflict triggered by the Sept 11 attacks of 2001.
Kabul, where he lives and runs a number of humanitarian programmes, is a battlefield. Civilian casualties from attacks by the Taleban and other militant groups such as the Islamic State in Iraq and Syria (ISIS) are an almost daily occurrence. According to figures released by the United Nations earlier this month, 1,662 civilians - a record number - were killed in the first six months of this year. Another 3,581 were wounded.
"I no longer make long-term plans and I'm comfortable with that," says Dr Wee, who was back in Singapore earlier this month to see his ageing parents.
Tanned, with a beatific face and a toothy grin, he radiates calm but is prone to loud guffaws.
Compassion probably runs in his veins. How else does one explain why he gave up a cushy medical career and the comfort of family, friends and familiarity to risk life and limb in the service of others?
His beginnings were humble. The younger of two sons of a salesman and a domestic helper, he spent his earlier years living in a three-room flat in Commonwealth with his widowed paternal grandmother and several relatives. His parents later bought their own three-room Housing Board flat in Holland Village, where they still live.
Dr Wee completed his primary and secondary education at Anglo- Chinese School before doing his A levels at Raffles Junior College.
The self-starter excelled in science, and went on to study medicine at the National University of Singapore.
The urge to help the needy and vulnerable surfaced early.
In his teens, he gave tuition and worked with drug addicts as a volunteer at Teen Challenge and the Singapore Anti-Narcotics Association.
"I don't think I have anything special. I believe everybody is kind and wants to help. They look for opportunities to help, just that some don't take the extra step of pursuing these opportunities," he says.
He recalls a former teenage addict he tutored for nearly three years, and who was on track to enter the polytechnic.
Unfortunately, the rehabilitated teen went out with some friends one night and got involved in a fight at Tampines Mall. In the ensuing fracas, someone pulled a knife.
"A boy was killed," recalls Dr Wee.
After hiding for several days, his student called him and they met at a cafe.
"He said, 'I thought my life was a rainbow and at the end was a pot of gold. It's all gone now.' He said he was going to turn himself in and tell the truth."
Dr Wee helped his charge's seamstress mother to find a lawyer for her son, even contributing to the legal expenses. The teen was charged with manslaughter and sentenced to seven years in jail.
"He decided to continue his studies so I wrote to the prison on his behalf. I heard that he finished his studies at NUS."
Unfortunately, Dr Wee has lost contact with him.
URGE TO HELP
I don't think I have anything special. I believe everybody is kind and wants to help. They look for opportunities to help, just that some don't take the extra step of pursuing these opportunities.
DR WEE TECK YOUNG, on helping the needy and vulnerable .
"I've tried looking for him but I guess he doesn't want to remember too much of his past. But I want to look for his mother, I want to find out how she's doing.
"I tried to get his contact again from a halfway house but they don't have it anymore," he says of his recent effort.
After graduating from medical school in 1993, he developed an interest in helping the disabled after reading an article about volunteers taking a group of quadriplegics for a day out.
He started a tetraplegia workgroup when he realised that hospitals here did not have such a database.
"Many of them were stuck in their rooms for years and were dependent on caregivers. I compiled a list by finding out from them who else they knew were in the same situation. After work, I would visit them to do a survey to find out what sort of support would help them most."
He says: "This wonderful lot of people taught me a lot - including not saying no to hope, never mind that it may be a false one."
His career, meanwhile, went well and he started a private medical practice with a group of friends.
However, the idea of taking his skills elsewhere had started percolating, especially after a backpacking trip through countries in Central Asia, including north Pakistan, Kazakhstan and Kyrgyzstan.
One day, a patient came to his clinic and told him that a non-governmental organisation (NGO) was looking for medical personnel to help Afghan refugees in Quetta, near the Pakistan-Afghanistan border. The Sept 11 terror attacks had triggered incessant bombings in Afghanistan.
The patient passed him a photo of two members of the NGO, a former Afghan general and his daughter.
That photo sat on his desk while he found out more about the work involved.
In 2002, at the age of 33, he packed his bags and left for Quetta - which he says was "a dusty no man's land, a Wild Wild West".
Taleban insurgents with walkie-talkies were everywhere.
"I saw misery and sheer human resilience. It was a shock to the system. How could people live this way and why?"
The situation became personal when he made friends with Najib, a young Pashtun orphan boy. Najib fled to Quetta with his grandmother after his parents were killed when the bombings began.
"He collected trash for a living. In the afternoons when he was done, he would often swing by to see me. One day, he came to me with his hands bloodied. The sack he was carrying was filled with glass syringes used by drug addicts. I tried to explain to him he shouldn't do it but I didn't succeed because to him, glass fetched more.
"Maybe I should have been more imaginative. It made me realise how uneducated I was."
One day, he invited Najib and his grandmother over for some Pakistani mangoes.
"His hands and feet were grubby so I scrubbed him down. Before we ate the mangoes, I took a photo and asked him to smile. His grandmother was very angry. 'Why are you asking him to smile? He has no reason to smile,' she said."
Najib came to visit him one afternoon a couple of months later.
"He told me he was leaving the day after and spent 10 minutes crying. He was going to Iran. I don't know if he made it safely. If he is alive, he could have joined the Taleban," he says quietly.
After two and a half years in Quetta, Dr Wee - named Hakim (doctor) by the Afghans he helped - decided to move into Afghanistan.
"Many of the Afghan refugees had decided to go back. I wanted to know what the journey was like," he says.
He ended up in Bamiyan province working for an international public health NGO. Bamiyan is the home of Buddha statues, once the world's tallest, carved into a cliff more than 1,500 years ago. These statues were destroyed by the Taleban in 2001.
Nostalgically, he recalls how he went to Bamiyan and walked into the city's only inn, which had just two rooms.
"It was called Map Copo hotel. The owner meant Marco Polo, whom he had heard about from travellers. He said he could make eggs in any way I wanted; he couldn't. He said it was very clean; it wasn't."
But the two struck up such a firm friendship that the owner invited Dr Wee to live with him, his mother and his two wives and half a dozen children.
"He took me in as his son, that was the only way I could get into an Afghan village. They don't like strangers, especially one who was a foreigner and an unmarried male," says Dr Wee, who remembers having to answer the call of nature at night by clinging onto trees on mountain slopes in minus 20 deg C temperatures.
He stayed in the mountainous village for seven years. His life took another turn.
"From my healthcare work, I began to learn about other areas including education, and community development," says the soft-spoken man, who also started conducting peace workshops for youth in Bamiyan University.
Inspired by the Afghans he had met, including Najib, he started, in 2005, A Journey To Smile, later renamed Afghan Peace Volunteers (APV).
In the beginning, the NGO comprised young Afghans - from different warring and ethnic groups - who wanted to speak out on issues, including their feelings about the strife and turmoil in their country.
The focus gradually changed. On its website, the group - which is not affiliated to any political group or religion - describes its mission as building "a critical mass of non-violent relationships for a green, equal and non-violent world without war".
Non-violence, he says, should be a way of life to show love towards other human beings and the environment.
Asked if that is a task too big and if he is setting himself up for disappointment, he smiles and says: "It's OK, I can handle it. It's not harming anyone."
Since its inception, APV has launched a number of initiatives, from social enterprises to schools to help vulnerable communities, including women, the illiterate, the poor and street kids.
The Borderfree Afghan Street Kids School, for instance, conducts lessons on reading, writing and mathematics for hundreds of children. There are also initiatives beyond Afghanistan, including a monthly Global Days of Listening programme, which connects people via Skype from conflict zones around the world.
APV has staunch support from many peace activists, including Nobel Price nominee Kathy Kelly, who founded Voices for Creative Non-Violence. It has also earned a string of humanitarian awards, including the International Pfeffer Peace Award - established by American humanist Leo Pfeffer and his wife Freda in 1989 - for Dr Wee in 2012.
The doctor, and other volunteers, are not paid any salary. The group only accepts funding for its initiatives from Afghans living abroad and Dr Wee's friends and supporters here.
"I don't need much. My funds come from the kindness of my medical friends and strangers," he says.
His parents are supportive of what he does but that does not make them any less anxious for his safety.
"I have asked for their forgiveness and come back to see them thrice a year," he says.
Dr Wee's idea of happiness is not about acquiring more and fancier things.
It is, he says, about spending more time on relationships and people, and healing the world with what it needs most: love.