I can be an arsehole, because I tend to be very observant of things (people's insecurities, abilities, talents, flaws, etc) so if I wanted I could emotionally hurt a lot of people. But I'm nice, and I am also extremely empathetic and sympathetic, so when I hurt someone I can see and feel their pain. A great motivator for peaceful resolutions is, of course, when the alternative is both sides losing.
OT: So yeah, get yourself angry or find someone you despise, shut down all of your empathy and point out all of their emotional and physical flaws with cold disgust.