This is not neccessarily a sign of idiocy, any more than schizophrenia is; but some people who need signs on their ceiling reading "breathe in, breathe out" in case they forget could have their sociopathy hidden beneath the easier diagnosis. Sociopaths can be very social creatures, and indeed some of the most successful men in business have some degree of sociopathy - all the easier to ignore rules when needed, or avoiding any consideration of the consequences of their actions.
But for the most part, the only people we know are sociopaths are those we see at a distance, and have the chance to view their actions alone and as a whole: it's much tougher to recognise one up close, as we're hard-wired for co-operation with other members of our group. It's much easier to think of Buddy Joe as being, yeah, a little "distant" maybe, but he does his job and buys a round now and then.
All are dangerous, but the degree varies. How far a step is it, do you think, from someone who leaves desperate phone messages like these at women's work numbers:
"I'm completely single; I'm very intelligent; I'm great in bed, I make great money - believe it or not, I'm a complete catch."
And a web site like this:
(Some of the worst Flash you'll see here)
And approaches women at damn near random insisting they have sex with him:
"Of course, most people who saw the poster thought it was a joke. I did, until Dimitri hit on me in Starbucks two years later. I was taken aback, mostly because of the way he looked: tall and broad-shouldered, with dark, gelled-back hair. A stranger on the street might nickname him “Dimitri the Lover” as a joke."
To being someone else who is charming, handsome, and kills people like this lovely fellow here?
The first man is simply a pathetic douchebag, even if he does have a few little quirks: like being a psycho misogynist with a note on his military record as having something "seriously wrong with him"; or drinking while on shift as a doctor; or having an "inappropriate self-use of perscription drugs". The second is obviously worse, being a mass-murderer and all; but their philosophies aren't all that different from each other.
And one of these two is teaching classes in how to be just like him.