Two people drift in a lifeboat on an uncharted sea. One says, "There! I see an island. Our best chance i to go ashore, build a shelter, and await rescue." The others says, "No, we must go farther out to sea and hope to find the shipping lanes. That is our best chance." Unable to agree, the two fight, the lifeboat capsizes, and the drown.
This is the nature of humanity. Even if only two people are left in the entire universe, they will come to represent opposing factions.
---The Bene Gesserit Acolytes' Handbook
"The Sandworms of Dune"