ryan avent
On agreeing how to disagree

The debate over the Height Limit is back, and earlier today twitter delivered unto me a piece from Atlantic Cities making “the urbanist case" for keeping the limit. I let loose an intemperate flurry of tweets expressing my frustration with the piece. As I reflect on the brief twitter conversation that followed, I worry that my frustration is being misunderstood. 

I would obviously love to be able to convince most people that my policy position on the height limit is the right one. But the pure fact of disagreement with my view is not particularly vexing. I’m used to having people disagree with me and to occasionally being shown to be wrong, in part or in whole. So while the classification of sub-categories of urbanism is interesting and useful, it’s not the source of my frustration with and feelings of alienation from “urbanism”.

What frustrates me is that many urbanists seem to be having an entirely different conversation. I am used to participating in, and I’d say I identify with, a community of wonky journalists — Economist colleagues, econobloggers, and wonks general — who may be motivated in their arguments by ideological bent but who, when confronted with a tricky question, instinctually head for public data or search the latest working papers. Published research isn’t the beginning and end of most policy questions, of course. But it provides a framework through which disagreeing parties interested in finding the right answer can get closer to the truth.

It is therefore bewildering to be confronted by the sort of loopy logic in the Atlantic Cities piece. Better, in the piece, appears to mean little more than “closer to the author’s conception of good”. We learn that, “parts of the region that are already relatively dense, such as downtown Washington, are fine as they are”. This seems to mean that downtown density is high enough that marginal gains in “environmental indicators” from density are no longer large (enough?), and such that taller buildings might require more energy-intensive materials to construct. Where does one begin to respond to such an argument! Why are those two variables the critical ones — so critical, in fact, that it’s acceptable not only to disregard literature on the economic costs of the supply limits but to act as if it doesn’t exist? 

And to argue that:

Building height has little to do with affordability. The argument that a limit on building height restricts housing supply and thus leads to higher prices is essentially the same argument made against Portland’s urban growth boundary. In both cases, it’s hogwash: if affordability were closely related to building height and density, New York City and San Francisco would be the two most affordable big cities in America.

Is just extraordinarily fallacious. I’m not sure I could construct a paragraph that more aggressively ignores the content of Avent-Glaeser-Yglesias arguments or more egregiously misattributes causation. 

Many urbanists have a view on what cities ought to look like. There isn’t necessarily anything wrong with that. But we should be willing to subject those views to empirical scrutiny. If urbanists aren’t willing to grapple with reasonable and rigorous assessments of the costs from restrictions like the height limit, and either explain in an empirically sound way why those assessments are wrong or why they’re right but nonetheless worth accepting, then they aren’t advocating for public policy. They’re just playing SimCity. Because the point of statistical analysis, however antiseptic and divorced from the view at street level, is precisely to make sure that the people living in those cities don’t get screwed thanks to hare-brained conceptions of what a city should be.

It’s not the disagreement that bothers me. It’s the manner of disagreement.