“Exponential Space” as a Fifth Urban Figure. Toward a Phenomenological Actualization of Françoise Choay's Quadripartition

This article investigates the interplay between human corporeality, architecture, and urban space through phenomenological analysis. Integrating Wittgenstein's ontology of reality as a "system of structured facts" (1922) with Kant's spatial concepts via Husserl's phenomenology, it establishes the body as a fundamental mediator of spatial intentionality, grounded in both aesthetic-sensual cognition (Formaggio, 1996) and existential finitude (Casey, 1996). The theoretical framework synthesises seminal architectural theories - from Geoffrey Scott's "enclosed void" (1914) to Henri Focillon's spatial masses (1934) - with contemporary neuroscience on embodied cognition (Gallese via Mallgrave, 2015). Through critical engagement with urban theorists, the study proposes transcending Françoise Choay's quadripartite urban classification (1970s) by introducing "exponential space" as a fifth typological category. This conceptual advancement responds to Kotler's exponential technologies (2012) and their paradigm-shifting impact on spatial perception. The proposed model addresses contemporary architecture's transformation through digital-physical hybridisation, requiring new theoretical constructs for evolving body-space-technology relationships. This phenomenological revision ultimately reveals an ontological mutation - where classical spatial theories must adapt to fundamentally new conditions of being in technologically saturated urban environments. The exponential space paradigm thus offers not merely an addition to Choay's categories, but a reconceptualisation of urban ontology itself through embodied cognitive frameworks.