Recently, the parents of Cheng Chieh, the 21-year-old Taiwanese undergraduate who stabbed four people to death and wounded 24 others, made a very public apology on their knees. There was a wave of anger towards the parents.
The general sentiment in Taiwan over last month's incident was that Cheng Chieh's parents were responsible in some way, and should be held culpable. In the words of the mother of one of the victims, they "did not teach him well".
Holding parents accountable does not appear to be merely a Chinese predilection.
Take the Columbine High School shooting in the United States in 1999, in which a pair of young gunmen killed 25 people and injured 24 others, before turning their guns on themselves. A subsequent poll found that 83 per cent of Americans believed the parents of the two shooters were partially responsible because they failed to teach them "proper values".
It is perhaps understandable that in such nightmarish situations, we need to explicate the incomprehensible so that the world would at least seem less arbitrary, frightening and senseless. At the same time, there is also a need to have an identified source at which that collective sense of outrage can be directed. But the inconvenient truth is that such things are never that simple.
Coming on the heels of that murderous spree in Taiwan was the similarly murderous rampage by 22-year-old Elliot Rodgers, who last month killed six people in California.
Then there was Adam Lanza, who one day in December 2012 shot dead his own mother, 20 schoolchildren and six adults in an elementary school in Connecticut before shooting himself in the head, as did Rodgers.
From the accounts that emerged subsequently, it was apparent that both Rodgers and Lanza had been mentally unwell since they were very young.
Lanza was diagnosed with Asperger's syndrome - a disorder that the American Psychiatric Association has recently subsumed into the wider category of autism spectrum disorder. The same diagnosis was suggested for Rodgers.
The parents of both these young killers, though divorced, were certainly very much involved in their upbringing - the mothers, in particular, went to great lengths to do what they could to help their sons.
Cheng Chieh, by his own admission, found life "empty and not worth living" but was too fearful to kill himself. With that warped and perverted logic, he proceeded to kill enough people so that he would receive the death sentence.
Professor Paul Appelbaum, a forensic psychiatrist at Columbia University, sees such cases as "suicides with murder as an epiphenomenon, rather than murders that happen to end in suicide".
Mass killings are relatively rare. As the number of mass murderers is small, and most either kill themselves or are killed by the police, it is difficult to make any proper study of them. In grappling for an understanding, one usual and almost reflexive postulation is that the perpetuator is mentally ill.