The theme of othering/intolerance returns, but this time in presenting the Other as the non-telepathic people, and the telepathy as an evolutionary advantage that gives them the right to eliminate the people of a lesser advantage. Evolution as a theme for regrowth of human kind is the driving force behind the ideology of the Sealanders.
Gordon Strorm, or "Spider-man," is presented in these chapters as Joseph Strorm's foil. They are almost exactly the same, coming from the same parents, but one was deemed to be abnormal and was banished, while the other, Joseph, falls within the standards of Purity and Norm. They are exact opposites and yet they mirror each other. In these final chapters, the two brothers confront each other in a war, and Gordon kills Joseph, before he himself is killed.