I used to have a really dreadful temper. I would break shit, throw shit around, and generally throw temper tantrums, even in high school. Hell, even last semester. But that is me no longer, thank God! Now I like to think of myself as pacifist. 
If you were to ask me in high school if I truly despised anyone I would say, "Absofuckinglutely." I would say I hated all those motherfuckers who were on the paper with me, someone who looked at me the wrong way this morning, the administration at my school, the security guards who gave me shit yet the truly dangerous kids run wild. 
Now, I don't hate anyone. It's too much wasted energy that only is a detriment to myself in the long run. No one wants that. If I dislike someone these days, if someone rubs me the wrong way, I merely pity them and pray for their sake they endure an experience that changes them.
Because most people, you can preach to them till your blue in the face and not a word will resonate with them. Because one must endure harsh experiences in order to truly learn, that's what I believe. 
I would never wish harm upon anybody, though. No one deserves dreadful things to happen to them. However, we all deserve to learn. And the way this occurs---it depends. If it's a fairly difficult route, then so be it. 
I've had to endure brutal shit to learn some lessons in the past. 
But I am obstinate, I will not listen unless I listen to myself. Call me narcissistic in that aspect. I suppose? 
I must bear hardships in order for an impact to be made.