Robert Hare's links page:
http://www.hare.org/links/index.html ; Dr Hare's book "Without Conscience" is excellent, and available in paperback. Also: Is Psycopathy and Adaptation? at
http://human-nature.com/nibbs/01/psychopathy.html, an interesting article by Arianna Huffington at
http://archive.salon.com/news/col/huff/2002/08/02/ceos/ . Also
http://faculty.ncwc.edu/toconnor/428/428lect16.htm ,
http://www.thedubyareport.com/bushnuts.html There's tremendous diversity in human intelligence. And some humans have evolved to prey on other humans -- in biological terms, it's just another evolutionary strategy. One researcher (it may have been Hare) noted that humanity is at the top of the food chain, and evolved its' own own parasites. Their job is to prey on other humans -- same as a cat's job is to prey on mice. And they have no more conscience than a cat. Their thinking is directed at conning, deceiving, stealing, killing; and if they can do those things well, they do not need to worry about consequences -- because they can always con, deceive, or kill their way out of them...
And they feel the same sense of satisfaction in a good con, a good rip-off, a good killing as we feel in a job well done; most of humanity evolved to work; they evolved to prey on us.
Again, a successful sociopath does not suffer consequences; he goes unscathed thru life exploiting, ruining, maybe killing others. Some become criminals, some become managers and CEOs, some become crooked cops, some try and take over the government.
To a sociopath, other people are objects -- other people are just so many pieces of meat to them. They have no empathy, no remorse, no conscience. It's all manipulation, violence, getting the upper hand, and ripping people off.
As for the overreaching; sociopaths have no empathy for their prey (us), and therefore have no natural sense of when they've gone too far. And no matter how much they steal, it's never enough. (Just like a cat will kill mice even when it isn't hungry.)
About 1% of the population is sociopathic; with the incidence in men being about twice that in women.
And if you look at the diagnostic criteria in some of the articles, you will be reminded of our selected pResident. From his grandiose sense of entitlement, his blowing up frogs as a kid, his substance abuse, his blowing one opportunity after another, his inarticulateness and his errors of syntax and grammar (which are typical of sociopaths -- their brains are wired differently), his fascination with punishment and killing of others, his brazen lying (and when one lie collapses, he comes out with another. And another. All with a straight face.), his phony emotions (because he doesn't have real emotions apart from anger, envy, greed, vindictiveness, and the like), and so on. He fits the profile of a narcissitic sociopath to a "T".