Just because a region is totally inaccessible to the outside world, it does not necessarily follow that the inhabitants (granted that the place is inhabited) are living in a totally savage state, absolutely devoid of the many conveniences and inventions of modern civilization. Tribes of progressive peoples have vanished--apparently from the face of the earth. What has happened to them? Where have they gone? Any number of answers might not only be possible--but might actually be true. It is hardly likely that a progressive people, no matter where, would degenerate to a savage state.