Psychologists like to tell this joke at parties: how many psychologists are needed to change a light bulb?
Answer: One. Provided the light bulb is willing to be changed, says Mr Jansen Ang, senior principal psychologist in the Singapore police force.
The point he is making is this - psychologists can only change a detainee's mind if he is willing to listen and change.
Mr Ang, 43, is currently the deputy director in the Home Team Behavioural Sciences Centre. He tells this joke during an interview on his work with Jemaah Islamiah (JI) detainees. The JI clandestine terror network was smashed in two security clampdowns in 2001 and 2002.
Since that first arrest, over 60 terrorists have been detained in Singapore. Of these, more than two-thirds have been released.
In 2002, Mr Ang and three other senior psychologists were asked by the Internal Security Department (ISD) to understand the mind of a JI terrorist and what motivated him to use violence in the name of religion.
Under the ISD's rehabilitation programme, detainees are helped to cut their ties with JI and start afresh with a new job and family support.
Mr Ang reveals that psychologists drew up profiles of the detainees based on information gathered during the interviews. Many of the detainees were very intelligent and fully understood what they were dabbling in.
They chose terror because they wanted to fight for Muslims whom they felt were being persecuted in other parts of the world.
"Some have deep-rooted ideas on their work in JI. It is very tough to change someone who is not willing to change,'' he says.
Read the full interview in The Straits Times today.