[Bluestrike2]

Outside the public consciousness, the term's only real professional use is limited mainly to some forensic psychologists because of the criminal justice system's rather peculiar requirements of psychology. Given the hoops it requires they bend through, I wouldn't look towards FP for diagnostic guidance. Robert Hare as well, but personally I tend to think of his work is sophomoric at the best of times and idiotic at the worst . He's also (in my opinion) a world-class prick, having used legal action to prevent the publishing of a critical paper that had already made it through peer review:

http://www.scientificamerican.com/article.cfm?id=critique-of...

But that's neither here nor there.

Anyhow, setting aside the lack of any diagnostic definition for either term, sociopathy has never been anything more than a synonym preferred by certain individuals. But if we're looking for some point of differentiation, one of the main reasons to prefer one synonym over another was to try and emphasize causation by social factors. Certainly not some sort of empathy switch.

Generally speaking, that confusion is part of the problem with both terms. They carry a lot of baggage and pop-psych definitions, but sorting through the muck and deriving some sort of diagnostic criteria is an exercise in futility.