In “Skin and Bones”, a chapter in Warped Space, Anthony Vidler is primarily concerned with exploring the space between, the liminal, and the relationship between inside and outside. He discusses the inbetween/liminal/inside/outside in the terms of the “fold” or pli. The fold is understood as both “a material phenomenon” (the actual) and “a metaphysical idea” (the virtual) that “joins the soul to the mind without division.” It is both a connector and separator, infinite and instant, and a threshold of the either/or. He positions this concept in terms of Leibinz’s idea of the fold and Deleuze’s interpretation of the Leibniz fold.
Deleuze’s understands the fold as both abstract and physical. Vidler translates, “folds exist in space and in time, in things and in ideas, and among their unique properties is the ability to join all these levels and categories at the same moment.” The fold puts the inside and outside in relation. Deleuze, in the final chapter of Foucault writes, “The outside is not a fixed limit but moving matter animated by peristaltic movements, folds and foldings that altogether make up an inside: they are not something other than the outside, but precisely the inside of an outside.” It is a moment of transition where all things exist and are mediated, joined both physically and conceptually.
Elizabeth Grosz, in Architecture from the Outside, extends (indirectly) the Deleuzian fold to encompass the real and virtual. Grosz structures the idea of the virtual, as opposed to the actual, as a way of relating and connecting past with present with future, and space with time. The interaction of the virtual with the actual allows overlaps and singularities of duration, memory, past, and present. It allows for simultaneity (a single point) and infinity to occur at the same time. “The past exists, but in a state of latency or virtuality . . . The present can be understood as . . . the point where the past intersects most directly with the body.” Virtuality relates the condition of the present within the scope of the past (and hence future) creating the body as the point of interaction with duration as a component of time.
Vidler takes these relationships of the inside/outside, virtual/actual, and past/present/future and extends them to architecture. He notes that some contemporary architects, such as Greg Lynn, are able to use digital media to realize the fold in both built and conceptual architecture. The results are new “blob,” “viscous,” and topological” forms. The inside is the outside. The new forms result from forces and motion that simultaneously respond to internal and external context. The fold can be the entire building or moments that mediate between separate pieces. It is a singular event existing in the present that disrupts and repositions our perception of architecture within time (past and future) and space.