"Our society is run by insane people for insane objectives. I think we're being run by maniacs for maniacal ends and I think I'm liable to be put away as insane for expressing that. That's what's insane about it." -- John Lennon

This phenomenon exists and it is high time we recognized it for what it is.

I recommend the work of Sam Vaknin. This video that he made is most relevant to my current video topic:
Children Psychopaths? Conduct Disorder
http://www.youtube.com/watch?v=gBSi246iqJg

Please see:
Psychopath in the family
http://www.youtube.com/watch?v=lZP6YKnxMHk&feature=related

This article is also very informative:
Conservative estimate: 'One In 100 Children Is A Psychopath'
http://www.sott.net/article/250569-Conservative-estimate-One-In-100-Children-Is-A-Psychopath

Also see:
Deconstructing myths about psychopaths: What are they really like?
http://www.sott.net/article/252141-Deconstructing-myths-about-psychopaths-What-are-they-really-like

"Not only do psychopaths lack emotions of conscience and empathy, but research has shown that individuals with Antisocial Personality Disorder (APD) are also indifferent to the threat of physical pain and to punishment in general. Without fear of punishment, there is little to deter the psychopath from committing criminal acts, if those acts represent the fastest route to gratification (Hare 1999)."

http://suite101.com/article/can-psychopaths-be-rehabilitated-a28604

This is true from the time they are children.
A child who is more than willing to undergo punishment or lose something if that is what it takes to hurt someone else, is your budding psychopath. I think that is THE determining symptom.

"There have been numerous, intensive programs designed to rehabilitate incarcerated psychopaths, and according to Dr. Hare, no program has yet proven to be effective. He notes that, in many cases, therapy can even help psychopaths hone their manipulative skills. His recommendation -- we all should educate ourselves about psychopaths in order to better recognize and avoid these predators (Black 1999, Hare 1999)." ibid

There is a very strange dynamic between the Psychopathic child and his/her Parents.
They are so outrageous and outraging that they force us to delve into the outer reaches of our consciousness in order to find solutions.
So, they serve a purpose.

HOWEVER, to say that the existence Psychopathy produces a positive effect and is therefore a necessary and sufficient condition for delving into the outer reaches of consciousness is specious logic.
There are better and certainly more salubrious ways of doing the same thing.
We tolerate Psychopathy because the Psychopaths in generations gone by have conditioned us to believe that pain is the necessary price we must pay for moral/spiritual depth and advancement.