What We Don't Know, and What We Can't Know

Three months ago, I wrote about the value of a career in urban planning as I began work on a master's degree in Urban and Regional Planning at the University of Minnesota's Humphrey School of Public Affairs. I had been a contributor to Strong Towns for months at that point, and an avid follower of the Strong Towns blog for a few years before that. So it's only natural that over the course of the semester that concludes this week, I've mused here and there about where some of the ideas we talk about at Strong Towns—"chaotic but smart", incrementalism, granularity, antifragility —fit into the various intellectual frameworks for planning that I've encountered in my classes.

The answer so far is an interesting mix of everywhere and nowhere.

Source: Wikipedia

Source: Wikipedia

On one level, you can pick a Strong Towns post at random and you're likely to encounter observations rooted in some insights that are almost gospel within the planning profession. "Chaotic but smart" is not a whole lot more than what Jane Jacobs brilliantly shook up the whole profession with half a century ago in The Death and Life of Great American Cities. In decrying the "urban renewal" policies associated with the wholesale razing of supposed slums such as Boston's West End, she observed brilliantly and correctly that such "slums" were often functioning neighborhoods with an intricate social structure and vast amounts of social capital invisible to outsiders. Destroying the physical buildings and relocating the residents, rather than facilitating their incremental upkeep and improvement by the community already rooted in that place, did certain and irreparable harm.

She was right. And we've absorbed her lessons when we talk today about how value is often found where we might not appreciate it, in what appears to the untrained eye to be "old and blighted." This is true on a simple, fiscal level. It's also often true on a complex sociological level, as Jacobs understood.

But none of this is controversial within the planning profession. Sure, at a contentious neighborhood meeting you might run into an angry resident who believes in a caricature of planners straight out of the 1950s—aloof, unaccountable bureaucrats too arrogant to recognize the non-technical expertise of those who actually live in a place. But in academia, and generally among practicing planners, that caricature is reviled. The technocratic master-planner wiping slums off the map with a wave of a pen is long dead. (Which is not to say that stupid and unaccountable decisions don't happen in local government today. They do. All the time. But the mechanisms are more subtle.)

Wait, it's not like SimCity?! I want my money back!

Wait, it's not like SimCity?! I want my money back!

Planning began its anti-technocracy (anti-orderly-but-dumb) revolution early, because urban renewal was so disastrously unpopular, and simply disastrous. Traffic engineering has been a much later arrival to that party, but it's well in the midst of the same revolution in thought now. This is epitomized by Chuck's accounts of the utterly different reception he gets when presenting Strong Towns ideas to older versus younger engineers:

When I’ve shown our video, Conversation with an Engineer, to groups of professionals, I’ve watched many of the old, stodgy engineers sit straight-faced with arms crossed while the younger crowd laughs and gives high-fives to each other. Have faith; change is coming.


Dharavi, Mumbai, India. Source: Wikipedia

Dharavi, Mumbai, India. Source: Wikipedia


The dominant trajectory in planning thought since the mid-20th-century has been increased recognition of what we don't know. Planning, in response, has expanded its toolkit to encompass more perspectives, more types and more sources of knowledge. Public engagement has become central to the work that planners do—public speaking ability is now arguably as important a job qualification for city planners as the ability to make a map. Recent scholarship has sought to improve public engagement to compensate for the biases of traditional engagement methods—the classic and, I'm guessing, familiar-to-many-of-us example being neighborhood meetings attended by wealthy, retired white folks who are in the position to spare the time and energy to attend, with nary a single mother of color in sight. There is a guiding belief here, and it is that the broader the base of knowledge—non-technical and informal knowledge very much included—that informs a plan, the better the plan will be.

Lately, planners in wealthy nations have even been absorbing valuable lessons from the megacities of the Global South. Many of these lessons have to do with urban informality—what can be accomplished with scarce resources when a lack of regulation (whether deliberate or due to lack of capacity to regulate) frees people to employ cheap ad-hoc solutions to their immediate needs. Lean Urbanism is one U.S.-based movement doing this. This kind of thinking is at the core of "chaotic but smart." It's exciting and promising.

Image Credit: Nicolás Boullosa. Licensed via CreativeCommons 2.0

Image Credit: Nicolás Boullosa. Licensed via CreativeCommons 2.0

The guiding idea again is that if you can just get as wide a range of perspectives into consideration as possible, you'll have a better plan. You'll be better at dealing with the incredibly complex chains of interaction that characterize a modern city. You'll minimize what you don't know. You'll show appropriate humility about the vast complexity of cities as systems and feedback loops.

And yet, what about when minimizing what you don't know isn't enough. What about when effective planning requires grappling with what you can't know?

This is where some of the ideas that distinguish a Strong Towns approach to urban development are less widely embraced and less likely to be approached head-on in either planning literature or practice. They represent a new direction in which we're still, I think, developing the vocabulary we need.



CityLab published a great piece last week titled "Why Aren't Urban Planners Ready for Driverless Cars?" It's about the fact that, despite the consensus that self-driving vehicle technology is rapidly reaching the point of mass-marketability, very few plans are concretely addressing and accounting for the issue. The reason is succinctly and memorably stated by one anonymous planner quoted in the piece:

“We don’t know what the hell to do about it."

Indeed, this is where every optimistic idea about perfecting our preparation for the future by gathering more information falls apart. The fact is, we don't know what the hell to do about what might be the most revolutionary technological disruption to cities since the car itself, because we don't know what the hell is going to happen as a result. We don't know how the market will respond, how the public will respond, how the regulatory regime will response. There are compelling arguments that this technology will be great for urbanism. There are compelling arguments that it will be terrible for urbanism. We flat out don't know yet. Even if we try to make policy based on assembling every bit of information we can and anticipating the most likely scenario, we have to deal with the question, "What are the consequences if we're wrong?"

Source: Wikipedia

Source: Wikipedia

Or. Here's a Strong Towns approach to this question: We can double down on pedestrian-oriented cities, knowing that walking on two legs is one technology that isn't going away anytime soon, and not put too many of our eggs in the driverless-car basket at all. Make cars, whether driverless or not, as irrelevant to our daily lives as possible. Are we potentially missing out on huge benefits to society that a more vigorous embrace of this new technology could afford us? Yes, and that is uncomfortable to some planners (and more generally, people) who get more excited about efficiency and progress than they do about resilience.

But we're exercising the precautionary principle in avoiding potential huge disruption. We redesigned our cities around a new technology once already. It hasn't gone well.

The way we normally conceive of planning is that we model future possibilities based on the best available information. We identify risks, and we ultimately hope to choose the course of action with the best average outcome, acknowledging that there is some uncertainty. But when the worst-case scenario is bad enough, or when we don't know how bad it is, avoiding the worst case should become more important than maximizing expected utility.

Nassim Taleb, Patron Saint of Strong Towns thinking, has a favorite parable in his work called the "Turkey Problem." You're a turkey and you've never heard of Thanksgiving. Every day that goes by adds one to your sample size of days in which you're well-fed and well-cared for and life is pretty cushy. Every day you become more and more confident in your prediction that the future will resemble the past. Until, of course:

We have blind spots. No amount of information will ever eliminate them all. There are risks we're incapable of mitigating because we haven't identified them, and some may be catastrophic. There's reason to believe we're entering an era of unprecedented disruption to our social and economic institutions and to our natural environment. How do we conceive of a corresponding approach to planning that is less about maximizing expected outcomes and more about the more urgent imperative of not being the turkey?

This is where planning thought seems to me to be lacking a bit of a vocabulary. There are a lot of people in the discipline talking about issues of climate change, food security, water scarcity, and so on. Resilience is a hot topic. But what are the principles of resilience? How do we make the case for places that can withstand not just the known risks to their future viability—fiscal, environmental, economic—but the unknown risks? This is really what we're implying when we ask, "How do we build Strong Towns?"

We need a toolkit of intellectual infrastructure for these dilemmas. Urban planners should be talking about the precautionary principle. We should be talking about fat tails and black swans. We should be talking about not just resilience but antifragility. And we are, but from where I stand, that discourse isn't as front-and-center as it should be. That, I think, is kind of where Strong Towns's niche is in terms of the planning profession. Addressing the question, "What does a planner do in the face of the unplannable?"