"So, what's Strong Towns all about?" is a tricky question I field often. How I answer depends on my audience and how much of their time they’ve offered me.

At a superficial level, we often champion certain visible practices that support thriving places. Read our work and you’ll pretty quickly get an idea of the kinds of policies that Strong Towns advocates like to see—but maybe not so obviously how they all fit together into a coherent vision.

At a deeper level, the Strong Towns approach isn't about what to think about cities and towns, but how to think about them. The Strong Towns approach treats cities as complex systems which cannot be neatly controlled or master-planned, but which rather become resilient when they are shaped by many hands through many small adaptations over time.

A tendency to get a little (or, okay, a lot) philosophical sets Strong Towns apart from many, if not all, of our peer urban advocacy movements or organizations, which are mostly concerned with a set of concrete outcomes or policy reforms. Not that there’s anything wrong with advocating for outcomes or policies; it’s just that we’re out here trying to also change the underlying mindset that guides civic leaders and community builders.

Readers sometimes tell us they’re a bit bewildered by the frequent references to abstract notions from disciplines like systems theory and psychology that show up in our articles and podcasts. If that’s ever been you, here's a list of 12 touchstone concepts that help underlie the Strong Towns view of how to achieve a world full of places capable of growing bottom-up prosperity. Some of these I was familiar with before I knew about Strong Towns, but all of them I have encountered and used in my work here.

This is deliberately not a list of concepts specific to the built environment or city planning. You're not going to see "induced demand, "design speed," "economic gardening," or "tactical urbanism" below. This list is more about how you understand systems and patterns—and while some of these ideas were coined by urbanist thinkers, none of them exclusively apply to cities.

1. Antifragility

It's for very good reason that we've called Nassim Nicholas Taleb the "Patron Saint of Strong Towns Thinking." Taleb’s best-known book, Antifragile, is a brilliant, often willfully difficult, stunningly original meditation on what makes certain systems prone to not only withstand disruption, but gain from it and come out stronger—hence making them “antifragile,” not merely robust.

An antifragile system derives its strength from the fragility of its many individual components: "In a good organic system, things fail early and fail frequently," says Taleb. The human body can withstand injury because individual cells die easily and are replaced; for the same reason, muscles can grow stronger in response to stress (the point of an intense workout). Similarly, an antifragile city is one subjected to constant small stresses, one whose leaders (both civic and private sector) make small experiments that aren’t catastrophic when they fail. “Fail early and fail often" is the mantra of the antifragile.

Further listening: “Lots of Small Earthquakes,” Strong Towns Podcast.

2. Complex versus Complicated

In the final and most important chapter of her magnum opus, The Death and Life of Great American Cities, the great urban theorist Jane Jacobs discusses "the kind of problem a city is." That problem, she says, is a problem of organized complexity. A city is a complex, adaptive system, in which the decentralized actions of countless people, all influencing each other in both direct and indirect ways, result in patterns of life and activity that no policy maker could have predicted or orchestrated.

The task of growing a resilient city is thus less like math or engineering—making sure all the constituent parts (like infrastructure and public services) are in good working order, making sure problems are anticipated and addressed methodically. It's more like conservation biology, mixed with a healthy dose of art and maybe a little bit of alchemy.

A lot of the problems that plague today’s cities result from the attempt by policy makers to replace complex, adaptive systems with those that are merely complicated. Consider the difference between an old-growth rainforest (complex) and a cornfield (complicated). The rainforest is a dazzlingly diverse environment in which species have evolved all sorts of symbiotic relationships with each other. Mild disruption is likely to result in the ecosystem adjusting rather than collapsing. The cornfield, by contrast, is a scientifically calibrated environment with predictable inputs and outputs. It is highly efficient at producing one thing: corn, delivered into a standardized supply chain which facilitates a whole secondary financial market. It’s complicated, but not complex, and certainly not antifragile. A new blight, a drought, a flood—any of these things can completely destroy the crop.

Our planning and financial systems, too, often turn our cities into monocultures. They are efficient machines for producing the same thing (like the subdivision, the strip mall, the stroad) over and over. The Strong Towns insight is that this comes at an intolerable cost in the form of fragility.

Further reading: “Cities Are Complex. So Why Do We Treat Them Like They’re Merely Complicated?” by John Pattison.

3. Cataclysmic Money

This one also comes from Jane Jacobs, who used the phrase in a pretty specific sense to refer to the flood of real-estate capital that hits a neighborhood when it catches the eye of profit-minded, outside investors. Unlike “gradual money” invested into a place by people with a long-term stake in it, cataclysmic money tends to go to activity that replaces the existing economic and social fabric of a neighborhood, instead of strengthening it. The normal flow of a river might support a lush marsh ecosystem next to its channel, while a flood scours that fragile environment clean and destroys it. So it is with a flood of cataclysmic money.

Further reading: “Gentrification and Cataclysmic Money,” by Daniel Herriges.

4. Chaotic but Smart

Carlson’s Law is a Silicon Valley adage that states, “Innovation that comes from the top down tends to be orderly but dumb. Innovation that comes from the bottom up tends to be chaotic but smart.”

A Strong Towns advocate tends to be someone who wants to see solutions to pressing local problems come from locals improvising to meet urgent needs. This process can be aided by higher levels of authority or government, but it cannot be led by them, or it will ultimately be unresponsive, solve the wrong problem, or get stuck in a box. We are better off with a thousand uncoordinated experiments, a few of which will be successful and can scale up, than one brilliant idea from the world’s best consultant that may or may not actually be the right idea, in the right place, at the right time.

Further reading: “The Least Dumb Idea Consensus Provides,” by Charles Marohn.

5. The Soviet-Harvard Delusion

The flip side of “Chaotic But Smart” is “Orderly But Dumb.” And the tendency to make things orderly but dumb is a human failing, not one limited to any political ideology, institution, or economic system. Nassim Taleb makes that last point trenchantly by referring frequently in his work to the “Soviet-Harvard Delusion.” The belief that the smartest people, equipped with the best analysis, can optimize a city or a society to improve human well-being is a grave error shared by the managerial technocrats of both left and right, both capitalist democracies and the authoritarian former Communist Bloc.

In Seeing Like a State, political scientist James C. Scott refers to a very similar concept as “high modernism.” The high modernist, Scott says, believes that society can be ordered according to scientific laws and models, and tries to replace the chaotic, emergent order of systems grown from the bottom up with something that is highly “legible” to top-down planners—often with catastrophic results.

We see the Soviet-Harvard Delusion in planning fads from “Smart Cities” to autonomous vehicles, from convoluted zoning and growth management regulations to large-scale economic development schemes.

6. Infinite Games

What does success look like in community building? One key to answering this question is to realize that, quite unlike competitors in a sport (sports being so often used as an analogy for the contests between places for growth, jobs, and prosperity), when you are a civic leader, the game you’re playing has no end. Your goal is to keep playing. Your goal is to keep making possible a good life in a prosperous place for your citizens, year after year, forever.

Winning, in an infinite game—a term used in Finite and Infinite Games by James P. Carse—is the absence of losing. And this entails a different mindset about risk from city leaders than we would tolerate in the private sector. A business can go bankrupt and the world goes on. But the failure of a city brings harm to more people outside of City Hall than within.

Further reading: “Winning Is the Absence of Losing,” by Charles Marohn.

7. Self-Adjusting Systems

Why does expanding a road often make traffic worse? Why does designing a road to be safer for drivers actually make it less safe? Why do policies that require affordable housing to be built often result in less affordable housing in a community as a whole?

Once you recognize that cities are complex systems, you see that you cannot isolate one variable in a complex system and then just solve for it, because everything affects everything else. And this can produce seemingly paradoxical results.

One such paradoxical finding is that having a wide, fast, high-capacity road through a city can make traffic in the immediate area worse, not better. This rule, called Braess’s Paradox, applies to streets and traffic congestion, but it’s better known as the “Ewing Theory,” after NBA legend Patrick Ewing. The story has it that, although Ewing was one of the greatest basketball players of his generation, his New York Knicks tended to play better when he wasn't on the court. Why? The other players stepped up their game and played more cooperatively in the absence of a dominant "big man" on the court. Each one contributed more to what was ultimately a more functional team effort.

Another rule of cities that belies the intuition of those not thinking of them as complex systems is Marchetti’s Constant. Coined by a physicist, Marchetti’s Constant is the rule of thumb that cities grow to roughly the size that allows most residents to complete their daily travel in about an hour by the prevailing transportation technology of the time. In ancient cities, this meant cities grew to a walking radius of 30 minutes; today, it means a driving radius of 30 minutes. Marchetti’s Constant is the reason that expanding highways to ease congested commutes basically never achieves its goal: Over time, commute times stay about the same, but people, on average, simply live farther out.

Complex adaptive cities are full of paradoxical patterns like this. Policy makers who don’t understand their complex nature are going to make the same mistakes—like assuming you can tweak one variable, like road capacity, and get a straightforward result—over and over again.

8. Incrementalism

A certain use of the word "incrementalism" in politics has given it a bad name. Especially to those who follow federal legislation, it often connotes slow, tentative, half measures that spend down political capital without meaningfully or permanently solving a problem.

We don’t mean that at Strong Towns. We talk a lot about incremental change, but we’re using the word in a sense closer to the way Silicon Valley uses it. There, incrementalism refers to a process driven by quick, iterative changes. “What’s the next, smallest thing I can do to address an immediate problem?” the incrementalist asks themselves. And then does that thing. Right now.

Think of it as rapid prototyping. Trying out solutions, iterating on what works, and discarding what doesn’t. Cities unleash this force by empowering many of their residents to act on the city in small-scale, bottom-up ways, whether as developers, entrepreneurs, tactical urbanists/amateur placemakers, or as activists of another stripe. When we do, change can actually be dazzlingly rapid and effective.

Further reading: “Incremental Doesn’t Mean Slow,” by Daniel Herriges.

9. The Lindy Principle

The Lindy Principle is a simple rule: The longer something has been around, the more likely it is to be around in the future. First articulated by academics in the 1960s, the power of Lindy is a favorite subject of Nassim Taleb, who calls the rule "one of the most universal, robust, and reliable heuristics“ there is.

Consider two books, which we'll simply call A and B. Book A was published 30 years ago, and it is still in print and widely read today. The other one, book B, was published 300 years ago, and it is still in print and widely read today. Which one is more likely to still be around and popular another 300 years from now? It’s book B, of course: that’s Lindy.

As Strong Towns advocates, Lindy teaches us to have respect for the profound wisdom of urban design practices that have been tested by literally thousands of years of human experience. There are characteristics that can be found in the smallest villages and the biggest cities on every continent on Earth, and that’s not an accident.

Lindy teaches us to have respect for the living traditions that allowed people with no formal training, modern design education, or advanced construction technology to build places that are not only considered beautiful and lovable today, but often exhibit elements of ingenious practicality and low-tech sustainability.

Over the modern era, we've professionalized and siloed architecture, planning, and traffic engineering. At Strong Towns, we think one of the crucial tasks facing our society is to recover our living traditions of how to build places that just work.

10. The Overton Window

What do you do when you need to change everything? How do you start a political paradigm shift?

Coined in the 1990s by Joseph Overton of the Mackinac Center, a libertarian-leaning think tank, the Overton Window represents the range of policy positions on a given issue that are broadly considered acceptable, mainstream, and nonthreatening. The Overton Window usually corresponds to the set of policies that elected officials will be willing to advocate and go to bat for—which is inevitably much smaller than the set of all possible policy solutions to a given problem. To either side of the window are views that, while they may have significant popular support, a politician seeking reelection is likely to deem too "extreme" to stake his or her career on.

At Strong Towns, we seek to start conversations that few cities are having right now. More than that, we seek to normalize conversations that few cities are having right now, whether that be about insisting on an accurate accounting of the fiscal impacts of development, dramatically rethinking the role and design of streets, or rejecting standard-issue practices such as the aggressive use of tax incentives to lure jobs to a community. In other words, much of our work, if we want to have a meaningful impact, must be to move the Overton Window in the direction of Strong Towns approach, so that city policy makers start implementing that approach without actually talking to us or crediting it to us.

Further reading: “Moving the Overton Window,” by Daniel Herriges.

11. Moral Foundations

Strong Towns is a unicorn among “political” advocacy movements: those that deal with issues within the realm of politics and seek to influence the actions of political officials. I know of no other such movement that can boast the kind of political diversity within its audience and supporters that Strong Towns can. We have crafted a message that appeals to liberals, leftists, conservatives, libertarians, and those (a greater number than you’d think) who are too outside of the binary to label their political thought in one of these ways.

The key is a deliberate emphasis on understanding and speaking to moral diversity. Moral diversity is not the same thing as ideological diversity—it’s not about opinions on the latest policy controversy. It’s about the gut instincts that we use to judge right from wrong. Moral Foundations Theory, an idea most associated with psychologist Jonathan Haidt, has suggested that liberals (small “l”) and conservatives (small “c”) place different amounts of emphasis in different ways on different moral principles, such as care/compassion, harm prevention, loyalty, sanctity, and liberty.

Our communities need and benefit from having people engaged in them with different moral instincts. We can account for each other’s blind spots and check each other’s excesses. This has nothing at all to do with partisan politics, but it has a lot to do with forming communities that are resilient because they are not monocultures.

Further reading: “Living with the Other,” by Charles Marohn.

12. Thinking Fast and Slow

Humans are not the rational, deliberative creatures we think we are. Research in psychology demonstrates, again and again, that most of our cognition consists of snap judgments and quick heuristics that, evolutionarily, allowed us to assess threats rapidly and stay alive in a perilous world. Only after the fact do we usually slow down, reason through pros and cons, and communicate to ourselves and others what we’ve done and why we’ve done it.

Strong Towns founder Chuck Marohn introduced me to the fascinating book Thinking, Fast and Slow by Daniel Kahneman. Kahneman describes the two modes of human thinking as System 1 and System 2. System 1 is our “fast” mode, in which we make nearly-unconscious snap decisions and quickly process just enough about our situation—and no more—to do so. System 2 is the rational, analytical mind that so many of us would like to think we’re governed by.

This has implications for persuasion. To be an effective advocate, for Strong Towns or otherwise, you need to understand how to appeal to someone’s System 1—to set them at ease and sell their gut on you as a trustworthy messenger—before System 2 will even kick in and give you the time of day.

It also has implications for community building. Ultimately, it’s part of the recognition of just how little we know, even those of us who think we know a lot.

Cities are the most remarkable of all human inventions, but they are collective inventions. They work best when many people—flawed, impulsive, biased, short-sighted people, just trying to meet their own needs—each play a small hand in co-creating them. And when the many, not the few, have opportunities to do so in meaningful ways.

12 Ideas That Embody How Strong Towns Advocates Think