The hypothesis of mobility transition.

The principle of the spatial diffusion of innovations to the laws of migration and specifically to the assertion that unless severe checks are imposed both volume and rate of migration tend to increase with are applied. Results are set within the same temporal structure that has been developed for the demographic transition and in accordance with the geographic axiom coherent spatial entities are identified. The hypothesis of the mobility transition is: there are definite and patterned regularities in the growth of and dischare of great quantities of chemical kinetic and nuclear energy. The temporal sequence of a 5-stage mobility transition is presented in outline form. A 5-stage vital transition is placed in parallel position to indicate contemporaneity (and probably interpendence) between adjacent segments of the 2 columns even though no suggestion of absolute date or duration can be offered. The highly schematic model shows the mobility and the vital transition as a kind of outward spatial diffiusion of successively more advanced forms of human activity. The verbal (or temporal) and the diagrammatic (or spatial) aspects of the model are complementary. The progression of 5 phases of spatial mobility is indicated for an ideal nation (one that averages out the demographic history of the entire universe of currently advanced countries) in which the potential migrant enjoys a full range of options. In addition the magnitude of movement that might have occurred but was obviated by the recent availability of superior transport and communications is hypothesized in 2 figures. During phase 1 genuine migration i.e. movement across appreciable physical and social intervals was uncommon. A sharp rise in urban-to-urban migration and in aggregate circulation during phases II and III with a subsequent deceleration or leveling off is implied by the available information. The time profile for migration obviated by improved means for circulating people is hypothetical. Eventually the empirical evidence may confirm the speculation that during phase III and later the broadening out of the circulators daily cruising range offered so many new social and economic options that many potential switches in residence were aborted. The migratory and circulatory currents of phases III and IV are more complex than those of phase II which are simply 1 great rural stampede funneled into several paths. In phase IV still more complex mobility conditions emerge. The flight from the countryside has slowed to a trickle and whatever movement persists is almost solely toward the city.