Cities Alive: Jane Jacobs, Christopher Alexander, and the Roots of the New Urban Renaissance
by Michael W. Mehaffy.
Sustasis Press, 2017.
Paperback, $20.

Reviewed by Gene Callahan

I first encountered the work of the great urban theorist Jane Jacobs due to the influence of my friend and mentor Sanford Ikeda, who has devoted a great deal of his intellectual life to studying and expanding upon her ideas. Even earlier, I had met the ideas of the renegade architect—and notably, “renegade” only because he was too respectful of traditional building styles and techniques!—Christopher Alexander. I discovered Alexander while proceeding along a seemingly entirely unrelated path of enquiry: my study of software design. Oddly enough, even though Alexander’s work is often neglected in his own field, among software designers he is renowned for his development of the concept of “pattern languages.” While Alexander applied the concept to buildings, neighborhoods, and cities, software “architects” were able to adapt it, with tremendous success, to software design. Due to my years spent as a software engineer, I was able to see the connections between the ideas of Jacobs and Alexander.

Given this background, I was intrigued to come across a book focused on showing how the ideas of Jacobs and Alexander might help us in confronting and solving the problems resulting from the massive increase in urban population that has occurred over the last several decades, and that will continue for the foreseeable future. To understand how significant and rapid this change has been, we might consider Wikipedia’s assertion that, “At the turn of the 20th century, just 15 percent of the world population lived in cities. According to the UN, the year 2007 witnessed the turning point when more than 50 percent of the world population were living in cities, for the first time in human history.”

As the number of people in cities waxed for economic reasons, the quality and sustainability of urban life seemed to be waning in certain respects. In many cases, the population of “urban areas” increased even as city centers decayed: people migrated to car-dependent urban outskirts and suburbs. As Mehaffy notes, this migration not only devastated many cities, it was also ecologically destructive and largely dependent upon taxpayer subsidies, in the form of government-backed mortgages, government-built roads, and such other taxpayer-funded goods as sewer systems, schools, emergency services, and so on. What’s more, many “urban renewal” projects, promoted to counteract the effect on cities of this flight from the core, actually made matters worse.

Mehaffy, following in the footsteps of Alexander and Jacobs, recognizes that a great part of the blame for the woes created by twentieth-century “rational” urban planning resulted from planners’ preemptive dismissal of the notion that centuries of experience and a long record of survival should lend any credence to a way of structuring urban life. Instead, they believed, the key to successful urban organization was to have a “rational” theory of how cities should be structured, and then to force the pattern dictated by that theory on urban residents, however reluctant they were to embrace it. Perhaps the apotheosis of this approach was the destruction in the mid-twentieth century of many poor, but functioning, city neighborhoods, and their replacement by “rationally” designed housing projects, built according to some planner’s theory. (Jacobs famously dismissed the typical result of these plans as “skyscrapers in a park.”) The planners completely ignored the intricate web of social connections that had existed in the “slums” they were destroying, since such a web was impossible to represent in their theoretical models.

Instead of recognizing that cities (and human social groupings in general) are instances of what Jacobs called “complex orders,” the rationalist planners believed that “The city itself would become a kind of machine for serving up whatever we needed or wanted.” But a machine is an entity deliberately arranged to embody what Jacobs called a “simple order”: for instance, to create a piston, the manufacturer purposefully crafts it so that its structure follows the application of a simple mathematical equation as closely as possible, and excludes the influence of “random,” unplanned factors to the extent the manufacturer can isolate the machine from their forces.

Despite their supposed dedication to “scientific approaches” to understanding living spaces, the rationalist planners apparently never considered that, if some form of organizing human life, or of structuring the built aspects of that life, has persisted across centuries, then the “null hypothesis” should be that such a persistent presence is evidence that that practice under examination is an important adaptation, an adaptation that promotes the survival of the humans who embrace it.

My colleague Nassim Taleb calls this principle “the Lindy effect,” named after the heuristic adopted by New York City actors hanging out at “Lindy’s Famous Cheesecakes”: if they wanted to predict how long a Broadway play would continue to run, but about which they had no knowledge other than how long it had already been running, their best bet was to guess exactly as long as it had already run! Thus, a play that had run for a week would, most likely, close in another week. However, if it survived a month, then the right guess was that it would last another month. Once it had made it for a year, then predict it would run for one more year. This idea, Taleb contends, applies to any social phenomenon that does not have some biological constraint on its lifespan (that is, just because my aunt has lived to 100, does not mean I should predict she will live to 200).

Contrary to our typical modernist bias, if some social practice has continued for several thousand years, it will most probably persist for a couple of thousand more. On the other hand, some recent, novel arrangement in social life, introduced, say, a decade ago, most likely has a shelf life of only a decade more. And Mehaffy does an excellent job of explaining how Alexander’s “pattern language” of architectural design and Jacobs’s extraordinary ability to recognize the factors that make some city neighborhoods flourish and others decline can guide us towards policy choices most likely to create a better life for the ever more numerous inhabitants of the world’s cities, since both of their approaches recognize the Lindy effect.

So far, so good. Unfortunately, Mehaffy is not satisfied with simply sharing his genuinely deep understanding of urban life, and his debt to Jacobs and Alexander as sources of that understanding. Instead, he seems driven to make his understanding of cities appear connected to and compatible with the latest trends in intellectual fashion. For instance, after noting that the ill-founded attempts of the rationalist urban planners were often grounded in understandings of the world modeled on Newtonian science (the science of simple systems) or stochastic mechanics (the science of unordered systems), he writes: “Most people are now at least generally familiar with ‘systems theory,’ and with fractals, algorithms, strange attractors, network science, and the like.”

This is an odd interloper in this book on cities: for instance, what are “algorithms” doing in there? “People” have been familiar with algorithms for over two thousand years: we still teach “Euclid’s algorithm” and the “sieve of Eratosthenes” to computer science students today. The leading founder of the “science of simple systems,” Isaac Newton himself, devised an algorithm for finding numeric roots. The existence of these and many other algorithms hardly stopped the butchery done on cities in the mid-twentieth century … so why are they relevant in this list? And some of the other items, such as fractals and strange attractors, while only recognized more recently, still appear more like trendy terms thrown in to make the practical knowledge of how to build livable cities more “scientific.” People around the world, using traditional wisdom, built aesthetic and life-enhancing cities for centuries before they had ever heard of “fractals” or “strange attractors.” I cannot help but wonder if Mehaffy is still in thrall to scientism, albeit a more hip version than that connected with “old-fashioned” Newtonian science.

Now, it is true that the increasing recognition, in scientific circles, of the existence of complex orders can represent a step forward. But if it is to do so, it is through warning scientists, and, more importantly, adherents of scientism, that these complex orders are not susceptible to theoretical mastery, but instead can only be (partially) tamed through experiential knowledge. Wisdom in dealing with complex orders, in so far as it can be verbalized, will appear in the form of commonsense heuristics, rather than universal, theoretical propositions.

Those who fail to recognize this will often ridicule common aphorisms as “contradicting each other,” as “He who hesitates is lost” appears, to those who want to interpret it as a “theoretical principle,” to contradict “look before you leap.” But interpreted correctly as pragmatic considerations, both are true: sometimes, hasty action is disastrous, but so, sometimes, is vacillation. Understood as heuristics, the two aphorisms remind us that we must carefully weigh the cost of hesitation against that of a rash decision. As Eric Voegelin noted, “every attempt to construe the commonsense insights, which refer to the order of [our] entire existence, as scientific ‘propositions’ according to the model of the natural sciences, and find beyond them ‘principles’ that could take the place of the real source of order, is a violation against the structure of the realm of man” (Anamnesis, 211).

We must now, unfortunately, turn our attention to the least savory part of this work, which is Mehaffy’s excursion into “philosophy.” Here he “butts heads” with both Plato and Aristotle, producing a spectacle much like watching a butterfly trying to pummel into submission a pair of elephants. In fact, I find it doubtful that Mehaffy has read much of either thinker; although they both have a single book appearing in the bibliography, neither book is actually cited in the text (as far as I could detect: I may have missed something).

Mehaffy is contemptuous of Plato’s work describing the transcendent “forms.” Of course, as R. G. Collingwood noted, Greek thought had reached an impasse trying to sensibly connect the transcendent and the immanent, and it was only with the formulation of the idea of the Trinity that the impasse was broken. Nevertheless, Plato was a great thinker, and deserves to met with arguments a little bit better than: “Going back to Plato, was the shape of a dorsal fin a timeless form, existing in some unseen realm? No, certainly not: it was a pattern that formed for comprehensible reasons …”

So, Mehaffy’s “refutation” of Plato is … “no, certainly not”? And why the sneering at the notion of “some unseen realm”? Is he not aware that much of modern science has consisted in the revelation of one unseen realm after another? And does he really think that Plato thought the forms were incomprehensible, rather than the ultimate source of comprehensibility?

Mehaffy continues, “So we can finally dispense with an external, transcendent realm of Forms, and shift our understanding to patterns.” Why “finally”? Has Western civilization been sick of these “Forms” for centuries, but just could not figure out how to rid itself of them until Mehaffy came along? Apparently, all it would take to rid ourselves of these louse-like forms was “of course not”! If we had only known! In any case, thank goodness for Mehaffy. Now we can jettison these annoying forms and replace them with … patterns. But consider that in The Republic Plato writes, “But the forms which enter into and go out of her are the likenesses of real existences modelled after their patterns …” In other words, for Plato, “forms” and “patterns” are synonyms … so Mehaffy has triumphantly replaced one of Plato’s terms for transcendent existents with another of Plato’s terms for them.

But since Mehaffy wants to boot transcendence out of respectable society, where do these “patterns” have a home? His answer is that, “As far as we are concerned, ultimately these are ‘only’ abstractions within own our own brains.” Well, well. But how can an “abstraction,” something distinctly nonmaterial, exist in a corporeal, flesh-and-blood brain? And if patterns only “exist in our brains,” then of what use are they in explaining, say, dorsal fins? Don’t worry, Mehaffy assures us, these patterns “are no less ‘real’ structures in the world.” If, “as far as we are concerned,” these patterns “only” exist in our own brains, then for whom, exactly, are they “real structures in the world”? For Martians, for angels, for God? I’m sorry, but this is simply pseudo-philosophical doubletalk, designed to impress the philosophically naive. All of the chapters on “philosophy” could have been left out of this book, and the resulting tome would have been less dense in both senses of the word.

As noted above, Mehaffy has certainly thought deeply about matters of urban design, and is clearly on target in his criticisms of much recent, sprawl-encouraging development. Still, after a salutary review of the large environmental cost of the deliberately planned, “strip-mall and tract housing” suburban development that dominated post–World War II America, Mehaffy claims we need a new “operating system of growth.” It seems he wants to repair the problems produced by top-down attempts to engineer society … with a new, better attempt to top-down engineer society. Still, he again hits the target when he notes that “the primary aim of architectural design today is, very simply, not to find the best possible solution for human environments, but rather, to create adventurous new sculptural works of art on a gigantic scale.”

Mehaffy is correct, in my view, to claim that the city should be organized for the good of all of its residents, and in noting that typically cities will be prosperous in proportion to how well they align with that ideal. But when he claims this is necessary “for justice,” I have to wonder how, having rejected the idea of transcendent values as something old-fashioned and “Platonic,” Mehaffy can invoke an ideal of “justice” as supporting the sort of city organization he (and I!) wish to see realized.

If he wishes to ground his ideas about urban living on noting “interesting and useful structural relationships and isomorphic properties, without respect to any metaphysical or ontological assumptions,” then how in the world can the notion of “justice” insert itself? Entities like minerals, metal alloys, semiconductors, and drugs all have “interesting and useful structural relationships and isomorphic properties,” but I have never encountered anyone who would term one particular alloy “just,” and another “unjust.” My point here is that, while Mehaffey’s regard for the common good as an overriding concern in urban policy is laudatory, his reflexive (see “of course not!” above) dismissal of granting any reality to the transcendent renders his concern for the “justice” of social conditions without any anchor. After all, the Gulag certainly must have had “interesting and useful structural relationships,” and slave-holding societies “isomorphic properties”: so, without any “metaphysical or ontological assumptions,” on what basis would Mehaffy condemn them? (And, please note, I’m sure he would do so: what I am pointing out is that, while Mehaffy’s heart is in the right place, his “philosophy” surely is not.)

Mehaffy has done his readers a great service in showing the mutual support the ideas of Jacobs and Alexander provide for each other, and has many salutary suggestions on urban design. It is unfortunate that he was unable to resist entering philosophical discussions in which he did not seriously grapple with the other discussants, but that excursion does not render this book unworthy of an urbanist’s attention.  


Gene Callahan is a Lecturer in Computer Science and Economics at St. Joseph’s College and a Research Fellow at the Collingwood and British Idealism Centre at Cardiff University, Wales. He is the author of Economics for Real People and Oakeshott on Rome and America.