A juggernaut is a term used to describe a force regarded as unstoppable, that will crush all in its path. (see related questions) A juggernaut is a term used to describe a force regarded as unstoppable, that will crush all in its path. (see related questions)
Psychopathy is commonly defined as a personality disorder characterized partly by antisocial behavior, a diminished capacity for remorse, and poor behavioral controls. Psychopathic traits are assessed using various measurement tools, including Canadian researcher Robert D. Hare's Psychopathy Checklist, Revised (PCL-R).
From wikipedia 'Psychopathy is a personality disorder characterized by an abnormal lack of empathy combined with strongly amoral conduct, masked by an ability to appear outwardly normal.'. The opposite would be someone that has complete empathy and upstanding moral conduct.