City Users

Populations and Collective Rationality

Urban structures, in which we walk or ride every day, are already deeply different from the urban images we have in our mind and in our hearts. Thus there is urgency for a profound reconceptu-alization of the intellectual and empirical tools we need for the study of urban social facts and processes. It would be naive to pretend to lay down a new theory of urban development, and I do not propose to offer one. But I would like to suggest an effort to analyze urban change, evading the straight-jacket of strict social ecological thinking and class analysis, based on the simple concept of popula-tion—namely, an aggregate of individuals defined by one or more simple traits—without any strong assumption about their rational collective behavior. This is contrary to the kind of theoretical assumptions we need in order to analyze classes, movements, groups, or organizations. To give an example of both the simplicity of definition and empirical power of the concept of population, it is sufficient to look at current patterns of urban migration from the third worlds to the developed ones. Migration flows are composed of individuals and households responding to personal circumstance; the effects of these aggregate decisions are far reaching precisely because they are a loose sum of individual actions.

Four Urban Populations

Based on these cursory considerations I propose to represent schematically various types of urban morphologies by using a simple combination of four populations differentiating out in successive phases; measurement of these variables is conceptually neat, and labels are needed only for discursive purposes.

From the Traditional City to the First-Generation Metropolis

In the traditional town, on which all the current thinking about urban life is still largely molded, the inhabitants, or the population living in the city, coincided with the population working in the city. The Industrial Revolution did not greatly affect this situation, because production of goods in the secondary sector requires mostly the shifting of raw materials, manufactured goods, and financial assets, while workers and entrepreneurs remain largely concentrated in urban areas.

The early metropolitan development that took place in the United States from the 1920s, and after World War II in Europe, can be essentially seen as a growing differentiation of two populations: the inhabitants and the workers. One can think of this early metropolitan development as two circles progressively separating one from the [Page 164]other while they both grow in diameter, as in a Venn diagram. While a sizeable portion of the diagram remains overlapping, the two circles come increasingly apart. Commuting is the consequence of this process. All in all, however, early metropoli-zation coexisted with the traditional urban structure to a fair degree.

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