Many commentators attribute the series' popularity to the altruism of its doctors and the emphasis on seeking to build peaceful relations between different species. John Clute wrote that "in the depiction of goodness may lie the real genius of James White." White's hatred of war and xenophobia is a constant theme of the series, notably in: "Star Surgeon", where the Monitor Corps fights a savage battle in defence of the hospital space station, to prevent the conflict from escalating into a full interstellar war that can only end in genocide; and in "The Genocidal Healer", where an alien race's sexual urges are almost eliminated by a plague and can only be stimulated by hand-to-hand combat.