Really its the same as any other mental conditioning that people in this society receive.

People look for groups. They categorize eachother, and anybody different (there are a lot of degrees of difference, but sexuality is, from what I have seen, a primary one) is alienated / looked down upon.

Do they want to realize it? Of course they dont. Ignorance is bliss in this world, people dont realize that their whole lives are more or less fallacies. I'll admit that I even look down on gays and even some races. It's subconcious, I can't do anything about it. Im not racist in actions or speech, but deep down I DO differentiate and react differently to certain situations based on the race and sexuality of those involved. The difference is that I actually realize i'm doing it, and look at it from an external point of view. Others? They are fully immersed in it and unaware. And they love it.

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