Isolationist Tribes

The BBC news had a video showing some footage of a nomadic tribe in the Amazon jungle who haven't been seen for 30 years. The video was shot by a team of researchers who were out looking for illegal loggers. They came across a primitive village of about 5 huts and 21 people, and they swooped in to take a closer look. The inhabitants were identified later by anthropologists who recognized the style of huts from photos taken in the 70s. The people from this tribe resist all outside contact, which is why nothing has been heard or seen of them since then.

Amazing as it may seem, there are indigenous tribes living in remote areas of the world, and who fiercely resist all contact from the outside world. The Sentinelese of the Andaman Islands, in the Indian Ocean, are among them. Their instinct to isolate themselves is so strong that after the 2006 tsunami -- which presumably caused destruction to their land and villages as well -- even then, they shot arrows at an army helicopter which was trying to investigate to see how much damage and casualties the tribes had sustained.

Reading articles like this make me wonder: how do the people in those tribes perceive us, who are supposedly more "modern" and "civilized" than they are? I would imagine that they do know about the outside world, and they certainly have seen the helicopters and planes that fly overhead, or the ships on the horizon. I doubt that they are so ignorant as to believe that these are gods. However, even knowing that there is a whole other world out there, they choose to ignore it and continue to live according to the way that their ancestors had lived for centuries.

Why is this, I wonder? Do they just simply lack the imagination and sense of adventure or curiosity? Or do they know something that we don't?