"Psychopathy is a personality disorder manifested in people who use a mixture of charm, manipulation, intimidation, and occasionally violence to control others, in order to satisfy their own selfish needs. Although the concept of psychopathy has been known for centuries, the FBI leads the world in the research effort to develop a series of assessment tools, to evaluate the personality traits and behaviors attributable to psychopaths. Interpersonal traits include glibness, superficial charm, a grandiose sense of self-worth, pathological lying, and the manipulation of others. The affective traits include a lack of remorse and/or guilt, shallow affect, a lack of empathy,...