Although I am aware of other beliefs I have known nothing else my entire life. to be wrong on this magnitude would be suicide
I was DF before and came back and now I'm inactive. Some would call me the king of dysfunction. I was baptized twice to boot in Natick, MA USA.
True story - I 'll get the gist of it anyway. Either TLC, Discovery, public T.V. History or Nature channels.
There are/was a group of people unknown to the world at one time. They also did not have a concept of an outside world past the rather large river. One day people ventured to their culture, outsiders. They came from the other side of the river (what we would basically call a god, visting us from the nether regions). To these people anything coming from the other side of the river was basically considered a god or something special or unusual.
However, once these outsiders left; that is, they went to the other side of the river, these people could no longer see them, although these people could be physically seen. It was because their culture or belief system would not or could not allow them to be in such a position to question their belief system.
This is a reason for leaving certain cultures in tact (if there are any left) The shock/realization would be too much for them to take.
Richard Belzer (a comic and actor I know but intelligent and with a very cutting acerbic cynical wit, one of my mentors)has a book, in it he describes why societies would crumble if the world ever came upon intelligent life else where in the universe.
Watch the movie, the gods must be crazy and II. It is comical but the point is made for the context of the movie that is "true" for some cultures. There is less and less of this kind of thing due to the "shrinking of the world"