Towards addressing transportation planning’s contradictions: The unified theory for transportation planning based on the capabilities approach

This article proposes a unified theory for transportation planning based on the capabilities approach which helps reconcile three key contradictions with which transportation planning has not sufficiently grappled. Those contradictions include the following. First, should transportation planners focus on opportunities or outcomes? Second, is travel good or bad? Third, how can transportation deliver value in a polyrational world which faces challenges in balancing universalist principles (meaning that they apply everywhere) and local context? To address these contradictions, the proposed unified theory firstly includes nine core principles, builds on the work of Vecchio and Martens, and centers locally produced understandings of accessibility (here refined to the construct of freedom of access ) as one of many capabilities necessary to live a life of dignity. Transportation planners’ key roles are to locally co-produce understandings of freedom of access as a capability—thereby bridging universalist ethical frameworks (ones which apply everywhere) into local circumstances through discourse ethics. Secondly, the proposed approach embraces the necessary linkages between freedom of access and transportation system use. Therefore, while travel is not of central interest, it is necessary to realize other capabilities. Third, the constructs of fertile functioning , corrosive disadvantage , and tragic dilemma enable transportation planners to uniquely co-produce (with residents and institutions) interpretations linking freedom of access-as-a-capability with transportation system use-as-a-functioning. Finally, the proposed unified approach reframes public involvement from project-specific initiatives toward a community-centered and domain-specific spatial ethics of transportation planning which revisits the changing meaning of freedom of access over time.