The bloody subway attack in Taipei last month initially created panic and shock among the public in Taiwan.
The subway operator said there was a sharp reduction in the number of passengers using the system in the first week after the killings.
This panic now appears to have subsided, but nervous passengers riding the subway in Taipei no longer spend their time surfing the internet on their smartphones or taking a short nap, but remain in a high state of vigilance.
Tunghai University student Cheng Chieh stabbed four people to death and injured 24 others when he ran amok on a train travelling between the Longshan and Jiangzicui stations on May 21.
The reason he gave to police and prosecutors for his random killings was: "I don't want to live because life is full of pain and pressure."
He wanted to do "something big'', he said, and as he did not have the courage to take his own life, he hoped the killings would lead to him to getting the death penalty.
His confession drew mixed public reactions, with some calling him a cold-blooded killer as he stabbed his victims in the heart or neck without hesitation.
Cheng told police he picked that route because the long distance between stops would allow him to have more time to kill.
The case, intensively covered by Taiwanese media, prompted non-stop discussions and analysis on TV talk shows.
Bizarrely, the intense media attention also encouraged so-called "fans" of Cheng to voice their support for his actions.
Some wrote posts on social media praising the killer, with some saying he had "taught the authorities a lesson".
The police have arrested at least 14 people for allegedly threatening to carry out similar attacks.
Amid all the debate and discussion it is clear that more can be done to ensure that similar tragedies never happen again. This includes asking teachers and parents to pay more attention to youngsters who show signs of being psychologically disturbed. So much emphasis is placed on young people's academic success these days that their emotional wellbeing is often neglected or ignored. In Cheng's case, he was described by his parents as a quiet child who was an excellent pupil at primary and high school, but struggled to keep up with classmates at university.
It is not clear how much this added to Cheng's sense of frustration or alienation or why he became obsessed with violent video games as he grew up.
What does seem apparent is that his parents cared little.
To the surprise of the public in Taiwan, Cheng's parents have yet to visit him in detention and in a letter of apology on behalf of their son they even asked the judicial authorities to quickly give Cheng the death sentence so he could "become good" in his next life.
A network needs to be set up so citizens can report people whose mental health poses a potential risk to others.
The expense may be great, but the need is clear.
Cheng told his high school friends he wanted to kill, and on several occasions he wrote about plots to carry out murders.
One friend alerted Tunghai University, but a college counsellor was later told by Cheng that his writing was just a plot for horror stories.
The university scheduled a more formal consultation with Cheng, but the appointment was never kept and the student went on to kill.