He described the house he wanted in psychological terms. He said, “I want a house that when I am inside I feel like I am looking at the world from the outside, and when I am outside the house it is as if I am inside the house.” This became the program for House 11a. It contained in its largest, most “inside” space an “inaccessible void.” It was a room with no doors and no windows and thus no access. Therefore, the most inside part of the house was conceptually the most outside, because it could not be entered. The subject could walk in and around the house, up and down, but it was not possible to enter this large “inaccessible void.” This inside/outside theme then suggested another external text as an initiating diagram for the house, that of a Mobius strip.
–Peter Eisenman, Diagram Diaries, 175-176