Truly we live in a house of mirrors. When you think that you are seeing other people and events, you are seeing little flashes of yourself, things in your life. This is all that we have and all that we can relate to.
You relate everything that you experience to you which is the only way that you can analyzy it. If you react negatively to a person or a situation, you are reacting to something in your own life, not them. If you hate transgenders for example, there is something in your own life you fear or are hiding.
There could be no other reason for violent hate of someone whom you do not know or interact with in anyway. If you get called a name, please remember they are calling themselves a name.
I offer this as proof of the above statement:
Look at someone who spews hatred and prejudice. They complain of others being prejudiced when they are the ones who are prejudiced. Those who complain the most about prejudice are the most prejudiced. Be different, and you see this.
Freud called it the id. This could be interpreted as a dark side of the personalty which needs to be considered. The Salem Witch Craft hysteria was about people projecting their dark side rather than integrating it.