Before revision: Large-scale states, so Morris, evolved because only they provided enough stability both internally and externally to survive the constant conflicts which characterise the early history of smaller states, and the possibility of war will continue to force humans to invent and evolve.
After revision: Large-scale states, says Morris, evolved because only they provided enough stability both internally and externally to survive the constant conflicts which characterise the early history of smaller states, and the possibility of war will continue to force humans to invent and evolve.