Psychopathy is a mental disorder characterized by antisocial behaviour, often leading to acts of aggression and violence. The victim, known as a psychopath, is to be distinguished from the psychotic, who is commonly treated as insane.
Psychopathy as a mental illness falls into a class of its own, and currently receives much attention from psychologists and behavioural scientists the world over. It is largely a phenomenon of our times. The principal characteristics of the psychopath are social insensitivity and lack of feelings. Often the intelligence of the psychopath is above average. Callous and selfish, the psychopath lacks the emotional qualities that make for normal interpersonal relationships, such as altruism, affection, empathy and concern for others, even though they may show a fanatical attachment to one person, animal or object. The psychopath is often also a sociopath, opposed to society in general, undisciplined and antisocial in his behaviour, and apparently devoid of conscience. [S]he has little sense of duty or collective responsibility. Varying degrees of psychopathy are to be seen in the road-hog, the bully, the mob-orator, the wife-beater, the baby-basher, the football hooligan, the vandal, the terrorist, the hi-jacker, the psychopathic killer. Psychopaths form the greater proportion of the population of remand institutions and prisons. Because their moral sense is regarded as deficient, the psychopath's condition has been described as one of moral insanity, or moral imbecility.
The DSM-IV Diagnostic Criteria for antisocial personality disorder include: (1) A pervasive pattern of disregard for and violation of the rights of others occurring since the age of 15 years as indicated by at least three of: (i) failure to conform to social norms with respect to lawful behaviours as indicated by repeatedly performing acts that are grounds for arrest; (ii) deceitfulness, as indicated by repeated lying, use of aliases, or conning others for personal profit or pleasure; (iii) impulsiveness or failure to plan ahead; (iv) irritability and aggressiveness, as indicated by repeated physical fights or assaults; (v) reckless disregard for the safety of self or others; (vi) consistent irresponsibility, as indicated by repeated failure to sustain consistent work behaviour or honour financial obligations; (vii) lack of remorse, as indicated by being indifferent to or rationalising having hurt, mistreated, or stolen from another. (2) The individual is at least 18 years of age. (3) There is evidence of conduct disorder with onset before age 15 years. (4) The occurrence of antisocial behaviour is not exclusively during the course of schizophrenia or a manic episode.
One analysis by researchers in 2005 contrasted core characteristics of women and men with psychopathy. They suggested that women often exhibited traits like debilitating impulsiveness (such as a lack of planning), thrill-seeking in interpersonal relationships, verbal aggression and interpersonal manipulation; meanwhile psychopathy in men tends to manifest with personal antagonism, physical aggression, violence and crime. Coldness and lack of emotion appears to play a far more central role in women's psychopathy than it does with men.
The "positive" traits of psychopathy is explored by Kevin Dutton, a psychologist at the University of Oxford, in his book The Wisdom of Psychopaths: What Saints, Spies and Serial Killers Can Teach Us About Success. In 2011, Dutton ran a survey in the UK titled "The Great British Psychopath Survey". Boardroom chief executives, journalists, police officers, the military, surgeons and lawyers were the professions where people displayed the most psychopathic traits. Dutton argues that certain personality traits within the psychopathy spectrum – including a coolness under pressure and less empathetic response to interpersonal interactions – can help people to deliver on their work without being "clouded" by personal impressions.
Psychopathy is not a category, it's a continuum. It is distributed amongst the population in varying degrees. Some people cause continuous destruction and some just need their symptoms managed. A growing body of neuroimaging research is helping to pinpoint some of the potential neurological abnormalities in the brain that may explain the symptoms.