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Wikipedia's Hate:
Hatred is an emotion of intense revulsion, distaste, enmity, or antipathy for a person, thing, or phenomenon, generally attributed to a desire to avoid, restrict, remove, or destroy the hated object. Hatred is also among the most common emotions that humans experience. It can be based on fear of an object or past negative consequences of dealing with that object. Hatred is often described as the opposite of love or friendship; others, such as Elie Wiesel, consider the opposite of love to be indifference. People may feel conflicting and complicated emotions or thoughts involving hate, as in a love-hate relationship.
Often the verb "to hate" is used casually to describe things one merely dislikes, such as a particular style of architecture, a certain climate, one's job, some particular food, or people who claim to hate something when they in fact merely dislike it.
"Hatred" is also used to describe feelings of prejudice, bigotry or condemnation (see shunning) against a person, or a group of people, such as racism, and intense religious or political prejudice. The term hate crime is used to designate crimes committed out of hatred in this sense.
According to evolutionary psychologists, hate is a rational reaction to people whose interests consistently conflict with one's own. Hate is an emotion, hence it serves the protective mode of a person. People whose behavior threatens one's own survival interests are to be hated, while people whose behavior enhances one's survival prospects are to be liked or even loved (as in the case of offspring and other genetic kin).
The passions of hate arise from several features of our thinking process. These include wanting to assign blame to others for our misfortune, protecting our self-esteem, a desire to strengthen our community, alleviating our fears (by destroying the evil others), and several types of errors in reasoning, including cognitive bias. The ability to quickly separate friend from foe is essential to self-defense and safety and provides the origins of hate .
Also, the feelings of hate can arise unexpectedly. If one has experienced maltreatment in the past, it is proven that one is more likely to maltreat and learn to dislike or "hate" people before they get to know the person. This is shown clearly in the pattern of people who are abused, ignored, neglected, or maltreated by their parents, and those children's tendency to become abusive or angry.
From wikipedia.
Hate is natural and very hard to prevent.
I grew up with our parents teaching us christian beliefs constantly.
I know that hating others is bad but, its just almost impossible to
prevent it from happening. Until one person can tilt this topic to one direction and makes it agreeable with everyone. I think this topic will go on forever.:D