From Speed to Sobriety: The Evolution of Urban Imaginaries and the Anticipation of Future Infrastructures

This article examines the evolution of urban imaginaries and their influence on infrastructure design, focusing on Japan as a case study. The futuristic visions of the 1970s, illustrated by Gunther Radtke and groups such as Archigram, celebrated speed, growth, and technology. By contrast, the ecological, economic, and social crises of the 21st century have fostered imaginaries centered on sobriety, resilience, and inclusivity. These shifts raise key questions: how can we reconcile past legacies with present challenges, and how can infrastructures anticipate the needs of a changing world?Japan, marked by demographic decline yet persistent large-scale technological projects, offers a privileged lens. Campaigns to dismantle obsolete infrastructures in rural areas show pragmatic adaptation, while the SCMaglev train embodies faith in technological progress. These tensions echo broader debates opposing advocates of ecological degrowth to defenders of modernization.Through case studies on mobility, energy, and ecological infrastructures, the article shows how imaginaries shape design choices. It highlights the challenges and opportunities of transition toward sustainable and resilient models, stressing the importance of inclusive, transdisciplinary dialogue to define the values and priorities guiding future infrastructures in an uncertain world.