These two chapters are the most science-fictionish of the entire novel, and are, of course, the heart of it.
Is my premise really so far-fetched? Most science fiction involving contact with aliens hinges around conflicts in the relationship. That's kind of a natural outgrowth of the reality that conflict also lies at the base of relationships between members of our own species; the fight-or-flight reflex left over from our prehistoric evolution governs all those relationships and far too frequently leads to the former outcome. Leaving aside special seasonal or situational circumstances, no other living species on our planet displays such chronic and persistent hostility to members of its own kind as do humans. But so ingrained in us is this response that we seem largely unable to avoid projecting it onto the putative aliens with whom we come into imagined contact. Even such a powerful intellect as renowned physicist/mathematician Stephen Hawking, for example, has lately gone public with a paranoid recommendation that we cease efforts to seek out and/or contact possible interstellar aliens, out of fear that they may prove more technologically advanced than we and seek to exploit that advantage to conquer or destroy us. Like fearful children, we cringe at hypothesized boogeymen under our beds.
So long as humans persist in this kind of self-destructive thinking (not really "thinking," more like knee-jerk reflexes), it's hard to imagine how we can hope to find any reconciliation even among ourselves.