Hello, Marc, I've been reading on the internet and it seems that the difference between the two terms is confusing even among psychologists.
In "wisdom of psychopaths" it says that they lack certain emotions, tha ability to feel fear as an example, that they can't empathise with people, can't put themselves in another person's place aka they see something in distress and can't feel mercy of compassion.
The internet says the same thing about sociopathy, some traits are related to psychopathy on one site while on another they are related to sociopathy.
So what's your take?
First off the terms psychopath/sociopath aren't used in psychology anymore.
Sociopath has been replaced with antisocial personality disorder
Both sociopath and anti-social personality disorder were/are used to describe the person. As was the term psychopath
The modern term psychopathy is about the behavior, not the person
Important because a lot of other types of conditions can result in these behaviors.
Then there is the issue of 'degrees.' See mental illness and conditions are on a continuum or scale. Here is an article that talks about extreme anti-social personality disorder.
That's an introduction to the professional (psychological/academic) meanings of the terms.
Something a friend told me way back when was a rule of thumb I've used ever since -- knowing that it's technically wrong. That is a sociopath is someone with no empathy, concern or compassion for others. A psychopath is a sociopath with a mythology.
So a sociopath is a sociopath, a psychopath is a sociopath with an grandiose 'crazy' overlaying everything else. Acting out their crazies are made worse due to their core sociopathic nature.
Hollywood usually gets this way, way wrong. Their villains are bad knock offs of psychopath. Psychopaths that couldn't have gotten to where they were because extreme sociopaths are not normally that well organized or able to control themselves. Add in the overlay of crazy and you get people who would have been caught long ago.
But two movies that come closest to demonstrating this distinction
Rob Roy: Archie Cunnigham = sociopath
Red Dragon/Manhunter: Francis Dollarhyde = psychopath