The aim of this research is to examine the moment at which the spatial organization of national and regional development was first formulated as a “plannable” problem; a decisive moment in the practical judgment of planning to regulate the relationship between national totality and regional multiplicities, and the beginning of the formation of a structural inconsistency between theory and practice in Iran’s spatial planning. To achieve an ontological understanding of this moment, the research was conducted through a combination of two approaches: critical realism and philosophical hermeneutics. This study is qualitative, interpretive, and fundamental in nature. Its analysis was carried out through an interpretive reading of development plan documents, spatial planning texts, laws, and institutional planning documents from the beginning of modernization to the Seventh Development Plan. The analytical process, moving within the hermeneutic circle among the historical horizon, planning texts, and the researcher’s pre-understanding, led to the identification of persistent patterns of questioning and semantic tensions in the formulation of national–regional development.

The findings indicate that planning has consistently attempted to stabilize development as a national totality that can be directed over time, while regional multiplicities have continuously introduced different futures and spatial uncertainties into this totality. The historical response of the planning system to this tension has not been the acceptance of two distinct spatial levels or two independent policy logics, but rather the continuous reconfiguration of the position of encounter through various modes of regulating development time—from spatial homogenization and the structuralization of temporality to living with uncertainty, to mediating national identity, and the assimilation of the “region” into the networked and chained logics of national development. Accordingly, the incompatibility of theory and practice is neither a resolvable gap nor even a mere consequence; rather, it is the internal logic of a dominant horizon of understanding that harnesses, suspends, or reabsorbs spatial differences to maintain coherence and the possibility of action within the time of development.