The Sociopath Next Door

We are accustomed to think of sociopaths as violent criminals, but in The Sociopath Next Door, Harvard psychologist Martha Stout reveals that a shocking 4 percent of ordinary people, one in 25, has an often undetected mental disorder, the chief symptom of which is that that person possesses no conscience.

He or she has no ability whatsoever to feel shame, guilt, or remorse.