I've dealt with people like this - somewhere in their brain or psyche, they have some kind of disconnect between their behavior, and how they think others perceive them. Very small children are like this - they don't understand that hitting little sister hurts her, because they haven't matured to understand empathy - they usually learn this around 4 or 5, but some adults I've known never totally grasp this - they don't see their actions apart from their feelings at the time they feel them.
This guy can still be dangerous. I'm no psychologist, but when people are that out of touch, they can be borderline psychotic. I'm still thinking getting medieval with this one.