Morality and Mental. Both of these conditions can be dangerous and hard to experience. I would not wish either on any one. However getting good mental health care is vital. Being honest with ones self and being willing to accept counsel and treatment is vital to living healthily. Good question.
Interchangable. Essentially the terms are interchangeable, with neither really being worse than the other. The full, true clinical term is antisocial personality disorder, the hallmark of which is for the most part, a person who has no conscience.