Have you noticed that true psychopaths are always very polite?

@CrazyMusicLover actually, and this is more semantics, what you are describing is more of a sociopath. A psychopath is psychotic,

@samueltyler2 That's how I ever heard it everywhere. But everybody states that it's not an official diagnosis and the term is outdated.
Psychopath - neurological condition affecting the normal function of oxytocin and adrenalin in a body, immune to stress, no physiological reaction in stressful situations like sweating, trembling etc., incapable of feeling love or infatuation, incapable of creating emotional bonds, smart ones usually achieve a high social status, no fear, no empathy, no guilt, no remorse, sensation-seeking, need for stimulation, limited and low intensity emotions, often a good self-control, calm and content "default" mood, cold "grey" anger that they don't act on immediately but usually plot a revenge, born that way

sociopath - poor self-control, impulsive, parasitic lifestyle, sensation-seeking, disregard for the laws, breaking laws, often end up in jail, disregard for other people, no empathy, no guilt, wants to fight either physically or verbally as a way of stimulation, can feel love and affection but only for very close people, explosive dysregulated anger they act on at spot, made that way due to traumatic childhood or growing up in dangerous lawless environment

That's how I've ever seen it defined.

@Guardian yup they’re usually very composed.