Spinoza's philosophy offers a radical conception of life that traverses nature and culture, humans and non-humans, built and natural environments, promising far-reaching implications for architecture. The relationship between Spinoza and architecture, however, has been nothing but a huge missed encounter. Despite the promise of recently emerging scholarship, not a single monograph has been published on this relationship for almost three and a half centuries. We may ascribe this missed opportunity to architects’ incidental neglect, or perhaps even deliberate disregard, of Spinoza's philosophy for denying them the privilege of situating themselves as hegemonic shapers of the built environment; or to Spinoza's multi-layered language and convoluted conceptual framework that resist easy translation; or even to Spinoza's controversial reception as a heretical figure and a subterranean philosopher throughout modernity. Regardless of what the motives may be, what is overlooked here is that there is much more to the relationship between Spinoza and architecture than meets the eye. My hypothesis is that there is a latent architectural treatise underlying Spinoza's entire oeuvre, including his private letters. But much like his unfulfilled promise of a treatise on physics (Ep. 83 to Tschirnhaus, 1676), or his unfinished political treatise, Spinoza's treatise on architecture is not to be found as a ready-made manuscript. Rather, its unravelling requires the discovery of discontinuous spatial hints and subtle architectural connotations buried deep between the lines in his philosophical archive. An introductory exploration of the promising relationship between Spinoza and architecture constitutes the subject matter of this chapter, an explo-ration that interweaves these fragmentary hints with a confluent architectural lexicon, orienting us towards a peculiar journey with the potential to redefine all the familiar terms we take for granted at the intersection of philosophy and architecture.

Onto-epistemology

At the outset of the Ethics, Spinoza introduces a new way of seeing reality, a new way of conceiving the cosmos, a new way of grasping life (E ID1–8). This novel vision is presented with the meticulous conceptual elaboration of an onto-epistemological triad consisting of substance, attributes, and modalities. Substance is the singular continuum through which all individual differences unfold.