How Cities Grow

In his review of The Economy of Cities [NYR, January 1], Richard Sennett accurately credits Mrs. Jacobs with significant insights in recognizing the importance of economic diversity to urban health, and in exposing the central role of cities in technological and economic development. However, his suggestion that she offers a prescription for curing American urban ills is seriously disputable, particularly since this prescription is heavily laden with questionable encouragements of eternal growth, a phenomenon for which she exhibits a positive passion.

According to Mrs. Jacobs, growth is a corollary of economic diversity and health; as Sennett puts it, “Human settlements survive and grow as they become more diverse and less rationalized.” Throughout her book, all cities are simply and inflexibly divided into two groups: healthy, growing ones and unhealthy, “stagnant” ones; as a matter of definition, cities which do not grow are cities which are dead. Mrs. Jacobs is incapable of recognizing the inherent limitations that a finite world puts on growth. She views the pollution and congestion of our large cities as “stagnation” problems: if only cities could continue to grow, out of their economic anarchy they would develop solutions to air and water pollution and find happy ways to re-cycle garbage. Her specific proposals on this subject, e.g. “mining” cities to recover valuable materials in wastes, and simultaneously eliminating heat pollution and conserving fuel by re-cycling the hot water from power plants, not only reveal her characteristic combination of self-confidence and naïveté (the latter proposal runs into trouble with the second law of thermodynamics) but also demonstrate an implicit and unwarranted faith in the ability of technology to solve all possible problems. The fact is that there are biological and physical limitations on growth and that all other living organisms obey these limits; man will also obey them, either involuntarily through catastrophe or voluntarily through creative (but prudent) economic, technological and social inventions. It may be time to begin to use our technology (and common sense!) to avoid problems, to escape the endless cycle of problem creation and solution that Mrs. Jacobs so dearly loves.

In the black ghettos and the third world Mrs. Jacob’s prescriptions may have more relevance, but here again contradictions to unlimited American growth arise: we constitute six percent of the world’s population and yet we consume a third of its raw material production, drawn from the whole globe. Apparently our continued growth and the fresh growth of the third world are not entirely compatible.

With an essentially historical and anecdotal method, Mrs. Jacobs has obtained interesting insights into the value of urban diversity, but this same method has led her to the misjudgment of economic growth as an eternal rather than transitory value. It is a fact that the entire historical record of urban evolution is, parallel with technology, largely a record of growth, but this period is a brief and unusual one in biological and human history. It has become apparent to many that today America needs urgently to begin to establish an ecological balance. The critical problem for the future will be the achievement of invigorating diversity (to please both Mrs. Jacobs and myself) within a context of overall equilibrium (to settle our accounts with Nature).

Stein Weissenberger

University of Santa Clara

Santa Clara, California

Richard Sennett replies:

Mr. Weissenberger raises an important issue, germane not to the work of Jane Jacobs, but to the wider issue of the “ecological balance” between city and countryside. First, as to his criticism of Jane Jacobs: I think it misleading to view Mrs. Jacobs as an advocate of unlimited urban growth per se; she has tried, rather, to change the terms of what we understand the real growth of a city to be. She is concerned with the survival power of cities in history; the dense city life she wants is opposed exactly to the incursions of physical “urban sprawl” upon the natural environment. These wasteland fringes of shopping centers and factories are not urban areas at all, she argues, because they have no resources to flourish and evolve as communities over time. The non-urban, non-rural glut of manufacturing concerns, shopping centers, or isolated tracts of houses comes into being rather out of arbitrary decisions by planners and developers looking for short-term gain. Mrs. Jacobs’s concept of the growth of cities is prescriptive precisely in the sense that she tries to show how the dense core of the city forms a better locus for future development, better with respect to both long-range economic survival and the possibility for face-to-face community life, than the sprawl outward of industry and housing to the suburban fringe in order to gain quick economies of taxation and transport costs.

Mrs. Jacobs’s idea of urban growth is prescriptive in a second fashion. She argues, not that technology as such can conquer all urban ills, but that technological growth responsive to the social ends of cities emerges when new means of diversifying the work and other social activities of the urban core can be devised. I agree with Mr. Weissenberger that her example of how this innovation would occur is strange, to say the least, but she makes no claims to write as a technical expert. The real value of her book is that, writing as an inspired amateur, she has achieved a rare insight into the values by which cities should be planned. Most professionals, in the process of becoming experts in a narrow urban field, have lost this insight into the city as a qualitative phenomenon, rather than as a place on the map.

Mr. Weissenberger’s letter raises a more general issue, however: how big should a city be in order to be in balance with the natural environment? It has always seemed strange to me that critics of the pollution of the American environment assume the growth of cities is responsible for this desecration of natural resources. But in fact, as Rachel Carson pointed out so graphically, the source of the pollution is to be found in the way the countryside itself is used—the spraying of dangerous chemicals on crops, the placing of factories in the countryside near the source of rivers rather than in coastal cities where the rivers empty out to sea, the systematic despoiling of natural scenery for gaudy vacation developments, and so on. These technological abuses were not “caused” directly by dense city growth: their cause lies rather in the fact that Americans have been unwilling to regulate the natural environment, to protect it from man, while willing to regulate rigidly the dense urban core, through arbitrary zoning codes, centralized master plans, and legal sanctions on economic diversification. It has up to now been a question in this country of operating at the extremes. At one end is “nature,” which men are unwilling to set proscriptions on, so that nature is violated without restraint by farmers, loggers, miners, and manufacturing concerns; at the other end is a city environment which men are afraid to leave at all alone and free, and instead seek to control under the vise of centralized, static, functional designs. The beauty and vitality of both country and city are in this way destroyed.

There is an even more peculiar aspect to this supposed “over-development” of our cities. In his pioneering study, Megalopolis, Jean Gottmann showed that in the past half-century, the growth of the urban corridor between Boston and Washington had actually created new forests and open land; this occurred as the population of this sector of America became more concentrated into the cities themselves; in other words, nodes of concentration emerged, rather than the more popular picture of a generalized urban sprawl. Indeed, what makes this urban corridor unique in the United States is that in the process of agglomerating large numbers of people into urban nodes, the suburbanization of the countryside has proceeded at a relatively slower rate than in the rest of the nation.

Gottmann and Rachel Carson suggest, therefore, that the real ecological crisis now is exactly that our cities are not densely packed enough with the manufacturing and housing activities they are uniquely fitted to contain. William Whyte has argued this ecological proposition in his recent book, The Last Landscape. Rather than translate our ecological crisis into the simplicities of over-grown urban development, what we need to do is figure out ways to save the country and the city from each other; this of necessity, Whyte says, demands that we learn how to reconcentrate and cluster productive and exchange activities in large metropolitan areas. The great achievement of Jane Jacobs is to suggest the guidelines, at least, along which innovation and growth of the dense urban core could take place.