The Oblique Function Theory in search of a dynamic and fluid urban morphology


  • Ertuğ Erpek image/svg+xml Middle East Technical University

    Ertuğ Erpek is a research assistant/student at the METU Architecture Department who graduated from the same department (B.Arch) as the top student in his class. He is currently doing a master’s degree (M.Arch) in architectural design and theory, focusing on the history of deconstructivism, computational design, and their reflections on urban discourse. His interests are contemporary architectural theory, urban architecture, virtual place design, and digital design theory. He participated in several architectural competitions throughout his architectural career and received prizes. He recently claimed the second prize in the Virtual Home Competition organized by Bee Breeders (Buildner) with his team.

  • Esin Kömez Dağlıoğlu image/svg+xml Middle East Technical University

    Esin Kömez Daǧlioǧlu received her BArch and MArch magna cum laude from Middle East Technical University (METU) Department of Architecture, where she also worked as a research and teaching assistant from 2008 to 2012. She completed her PhD research in 2017 at Delft University of Technology, Department of Architecture where she also taught design and theory courses at the Chair of Architectural Composition and Public Building. Currently, she is working as an assistant professor at METU, Department of Architecture. She have published numerous articles in journals such as Architectural Theory Review, OASE and METU JFA.  



dynamic form, fluid morphology, the oblique function theory, topology, urban section


Today's cities are dynamic nodes where copious urban flows intersect. These flows have distinguished characteristics: the flow of money, the flow of vehicles, the flow of people who migrate, and the flow of information. The flows' amalgamation, intersection, and conflict form contemporary urban configuration and space. Many methods, such as historico-geographical, process typological, and space syntax in urban morphology studies, aspire to analyze, discuss, and design these flows. These, which have been practiced in English, Italian and French schools in Europe since the 1960s, have allowed the development of different research methodologies in the search for urban form. The article examines the postmodernist urban topo-morphological approaches, which developed in parallel with the French typo-morphological method influenced by the Italian school and the urban space perception studies of Gordon Cullen and Kevin Lynch through the Oblique Function Theory. In order to go beyond the Cartesian urban plan analysis of typo-morphological methodologies, topo-morphological approaches reexamine flows with paradigms of urban topological surface, fluid and dynamic morphologies, and architecture-landscape-infrastructure integrity. The Oblique Function Theory was theorized by architect Claude Parent and philosopher and urban theorist Paul Virilio in 1963 under the Architecture Principe group as an example of these approaches. Parent and Virilio use and utilize inclined surfaces, rejecting archetypal spatial components such as columns, walls, and roofs. The duo with inclined surfaces extrapolates the concepts of habitable circulation, mediated structure, fluid, and dynamic form in their projects with a topological perspective. Through urban sections rather than urban plans, form a topological and oblique urban order dominated and ushered by flows. The paper discusses Parent's oblique projects: Les Inclisites in 1968; Les Ponts Urbains in 1971; and Incision Urbaine in the 2000s, obtained from slightly researched archival materials and drawings to argue whether contemporary urban dynamics and flows would possibly create a contemporary urban morphology methodology and sui generis tropes with topo-morphological approaches.


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How to Cite

Erpek, E., & Kömez Dağlıoğlu, E. (2023). The Oblique Function Theory in search of a dynamic and fluid urban morphology. Journal of Design for Resilience in Architecture and Planning, 4(2), 148–159.



Research Articles