Generally speaking (exceptions may exist), when you think that someone is evil,
you won’t try to understand the mind of the wicked from his/her stance.
However, if you cannot see the mind of the evil, you cannot understand the motive of the killer,
namely the real cause of the homicide.
And if most members of a society including yourself do not understand the mind of the murderer
i.e the motive of the murder, there emerges the risk that the prevention of the murder will become difficult
(if it is a democratic nation, there may be an even bigger risk).
In addition to that, it will become difficult to love a murderer.
For the ones who believe that not to love your enemy is a sin, this may also be dangerous.
Of course, I am talking about a risk = the possibility only.
By the way, you can decrease the degree of danger by just simply imagining that "the one is not evil." But it is not easy to imagine that he/she is not evil, not even for a short while.
Whatever called, he/she is really a cruel killer!
"I have absolutely no idea how I can think that the one is not evil!"
There may be such readers.
So, I would like to show an example of thinking here, which enables you to regard him/her not being evil.
Please do not misinterpret this. The writer does not have any intention to say, "You should adopt the following sort of thinking."
It is not my aim. Please take the following just as a methodology, showing the possibility of seeing a serial killer as not bad if you think of it in this way.
By the way, the theme of this book is not about criminal psychology, so the following explanation is very simplified.
(If you are interested in psychology of serial killers more, please read the books written by Mr. Ressler, who is a veteran of FBI, who developed the method of criminal personal profiling.)