How evil can a person be? Part 1

We often come across people who jeopardise our safety , has evil intentions . We wonder what's running in their mind . How can a person who was close to you have intentions which are out of the ordinary. Is it normal for a person to undergo a drastic change in behaviour?. What can we do in that situation ? Stop , keep no thoughts in your head . Put yourself in that person shoes and think ! . Do you still feel you wouldn't do that and a particular thought of harming a person wouldn't cross your mind. That's normal, because of the history of that person along with you . Your mind would trick you into feeling that you wouldn't think that way.