John says that his people, the Hill People, are "not ignorant like the Forest People . . . We do not eat grubs from the trees, we have not forgotten the old writings." From this we can infer that the Forest People, at least from John's perspective, are rather primitive and uncivilized. When John says that "we have not forgotten the old writings," this also implies that the Hill People and the Forest People have shared roots. They both, it seems, were faithful at one time to "the old writings."
On his journey, John passes many "Dead Places." He says that "The Forest People are afraid of them but I am not." Here then John implies that the Forest People are cowards, but, more interesting perhaps, is that John seems to continually use the Forest People as a reference point by which to define his own character. He defines himself in opposition to the Forest People.
On his journey, John also passes "hunting parties of the Forest People without their knowing." The intended implication here is that John, by virtue of his magic, has managed to fool the Forest People. However, this reference to the Forest People could once more tell us more about John than it does about them. It seems more likely that the Forest People do see him but are indifferent to his presence, rather than that they don't see him because he has magically made himself invisible.
A little later in the story John remarks, about a particularly vulnerable moment on his journey, that "The Forest People could have killed me without fight." This adds to John's impressions of the Forest People as brutish, violent and primitive.
Ironically, many of the failings which John accuses the Forest People of are arguably failings that he and the Hill People are guilty of too. The fact that he and his father read signs in sticks thrown to the ground, might, for example, be deemed a rather primitive form of divination. And, as we learn at the end of the story, John and the Hill People have also been guilty of the ignorance that John accuses the Forest People of. John and the Hill People have been ignorant as to the true nature of their gods.