This essay investigates the invention of the concept of space in architecture, in a process that took place from the latter part of the nineteenth century to the first decades of the twentieth century. Beginning with a reinterpretation of Immanuel Kant’s theory of space as a form of intuition, which comes acrossin Gustav Fechner’s claim that aesthetics must be done ‘from below’, it then continued through a series of reflections on the idea of empathy in Robert Vischer, Adolf Hildebrand, Heinrich Wölfflin, and August Schmarsow. These debates formed the implicit backdrop for the architectural theory of early modernism, notably in the writings of Sigfried Giedion, in which a theory of spatial interpenetration forms the bedrock for an analysis of architecture as a tool for the organization of social relations.

Drawing on Gilles Deleuze and Félix Guattari’s claim that philosophy should be seen as the art of forming concepts, I argue that similar creation processes can be found in the artistic field, connecting components from psychology, philosophy, and a host of other disciplines. While not invalidating Deleuzeand Guattari’s model, the example of space beckons us to reformulate their theory in a more complex manner than comes across in the triad philosophy–science–art, which will prove useful for theorizing historical transformations and ruptures.