Problem

Metropolitan regions will not come to balance until each one is small and autonomous enough to be an independent sphere of culture.

Solution

Wherever possible, work toward the evolution of independent regions in the world; each with a population between 2 and 10 million; each with its own natural and geographic boundaries; each with its own economy; each a world government, without the intervening power of larger states or countries.

… within each region encourage the population to distribute itself as widely as possible across the region — The Distribution of Towns (2)