http://www.psychologytoday.com/blog/your-online-secrets/201409/internet-trolls-are-narcissists-psychopaths-and-sadists

Psychopaths? No. Narcissists and Sadists? Yes.

"Psychopath" is a problematic term which stigmatizes (or even taboos) undesirable behavior but also suggests that those individuals are unfit to live as they are in their "natural state." No. Internet trolls are people who know exactly what they are doing, and find pleasure in it. We could go full on latent sexual pleasure if necessary, but I don't find the proliferation of schadenfreude something that needs to be diagnosed or treated.

DO NOT FEED THE TROLLS
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