The color scheme of this fantasy friction-of-distance map would also
offer a rough and ready guide to patterns of cultural and commercial, but not
political, integration. Where the red color spreads with the least resistance,
along river courses and flat plains, there one is likely to find more homogeneity
in religious practices, language dialects, and social organization as
well. Abrupt cultural and religious changes are likely to occur at the same
places where there is, as with a mountain range, an abrupt increase in the friction
of distance. If the map could also show, like a time-lapse photograph, the
volume of human and commercial traffic across a space as well as the relative
ease of movement, we would have an even better proxy for the likelihood of
social and cultural integration