Helix Bridge, Singapore (Photo: Farhul Azmi/Unsplash)

"Urban scaling explains everything!”

It was a message pounced on by popular reviewers in 2017 with the publication of Scale by SFI Distinguished Shannan Professor Geoffrey West. But in academic circles, the theory has moved far beyond what West popularized in his book — and it has also provoked heated debates. 

“Many researchers, and especially urban economists, have loudly rejected the work,” says José Lobo, faculty in the School of Sustainability at Arizona State University. “The criticisms have been serious and have accumulated.” 

So far, the debate has been conducted in slow volleys through the pages of top journals. But now, dissenting voices come together for the first time. 

SFI’s collaborative ethos often centers discussion that reaches across disciplinary lines. This meeting, "Integrating Views on Urban Scaling: Foundations, Criticisms, and Extensions" happening May 15-17, extends that open-mindedness even further, inviting to the table some of the theory’s most prominent critics. 

Urban scaling theory is most famous for highlighting the disproportionate growth in economic output and innovation when a city grows linearly in population. These “superlinearity” findings, while easily hyped, are not necessarily novel, and detractors assert that urban scaling theory adds little to existing approaches by urban economists and economic geographers. Others question the robustness of reported scaling results or point out that it fails to identify its underlying generative processes. 

“It is not often that SFI convenes a meeting at which criticism of SFI-sponsored work is explicitly aired and confronted,” says Lobo, who is the event’s organizer and convener. The three-day summit keeps one-way presentations to a minimum, instead directing time to mutual listening. 

One looming question hits at the heart of urban studies itself: what exactly is a city? 

“What is the thing people are studying? A built environment, or a social network?” asks External Professor Scott Ortman (CU Boulder). Ortman leads SFI’s Social Reactors Project, which conceptualizes cities not as physical spaces so much as “social reactors,” hubs of human interaction that fuel technological change. 

“This debate is raging at the moment,” says Lobo. It’s “a crucial one, for if we are to advance in our understanding of urbanization we need to be clear that we are measuring the right thing.”

“The most important tasks of the workshop,” says Lobo, are “to clearly place urban scaling work in the context of the rich work that has been done on urbanization and the origin of cities by many disciplines, assess the empirical strength of the reported scaling results, [and to] clarify just what is it that we have learned from the urban scaling work.” 

In doing so, the working group will build on one of SFI’s signature strengths: putting dynamic thinkers not in the same journal but in the same room to clarify what urban scaling adds to an ongoing, urgent conversation with implications for cities past, present, and future.