We are two organisms. There is our body, which includes our brain and its genetic predisposition, and there are our beliefs. From our perspective, it can seem like beliefs, values, and cultures are ephemeral and unreal, as they are also incorporeal. Yet at the same time, they behave very much like living organisms. They breed with each other, they mutate and evolve, and they via over territory, be it individual human minds or an entire national ethos. In medieval Europe, the Catholic Church referred to heresies as contagions, as though they were like a disease—a virus—of the mind. Ideas were also thought of as independent spirits which could possess people. In way, this is just a colorful way of describing a real process. People do become very much possessed by their beliefs, and these beliefs dictate their behavior as surely as their genetics do.
Humanity evolved for this. We are not creatures ruled solely by instinct, but instead the rulership of our behavior is shared with culture. This has given us an edge over other species, as a culture can evolve more rapidly than a genetic pool. When we are young, we eagerly model ourselves after our parents and the other people in our lives. We not only walk like them and learn their language, we also assume their beliefs. For a while, we share many things with them, including morals and religion. In time, these might be challenges by other beliefs, but this American notion that it's the “individual” challenging the norm is deceptive. How many of us, when we lost our faith in Christianity, did it because we came to that conclusion entirely on our own? Almost all of us had already been exposed to the possibility of religion being flaws. A quick glimpse at movies, literature, and music over the last thirty years reveals a growing distrust for religion. In our young minds, a war took place between the belief in religion and the belief in no-religion. In the end, one side won. One set of beliefs claimed us as surely as a wolf claims a swath of forest for himself.
This phenomenon can also be used to describe the development of personality, not just of belief. I tend to be analytical and sceptically, but these attitudes were not an inherent part of my personality. I remember in high school as I first began to develop these traits. I pushed myself to be more like the heroes of my imagination, the Socrates and Kants. Had I not pushed myself to become like these people, I would be somebody very different today. Now, I can't shake this attitude, at least not easily. Sometimes I just want to relax, to stop analyzing people and society so much, but doing so requires concentrated effort. I am so thoroughly possessed by this spirit that I cannot shake it. In way, we have bonded and become a single organism.
Similar ideas spread through culture, especially with the aid of mass media. Movies and literature portray a violent world and perpetuate feelings of fear in the populace. I know people who have succumbed fully to these cultural beliefs in a violent world and it makes them shut-ins. They rarely leave their homes or routines out of fear. Perhaps they think they'll inadvertently trespass upon gang territory, or maybe they'll cross the path of a psycho killer. My first year in Austin, I was terrified of West Campus, because I thought it was the ghetto and that I'd get shot if I wandered around there at night. It was a fear completely unfounded on my own experience, but rather cultivated through a childhood of media consumption. Although many of us may mitigate these cultural misconceptions through real-life experience, doing so is like removing a tumor. Often just enough of the cancer remains that it grows back in time.