Eisenman rejects Cartesian rationalism and its notion of the point being the smallest element, and the Modernist interpretation of figure/ground, the linear ground slab as "the neutral datum, projecting its autonomy into the future."
"In the idea of the fold, form is seen not only as continuous but also articulating a possible new relationship between figure and ground, thereby breaking up the existing Cartesian order of space."
"continual variation of matter... characterized through the agency of the fold." "first defined culturally in the baroque"

Eisenman replaces traditional architectural theory with the notion of the fold as a "third condition", somewhere in between plan and section, figure and ground.

"the idea of the fold gives the traditional idea of an edge a dimension," opposed to an abrupt line the fold offers a volumetric dimension which Eisenman argues can be used as a re-framing of sorts, and applies it to social organizations and the urban environment.