Regardless of the earlier references to the family of regular polyhedra and their significance in life's architecture on a moving, spherical earth, humans had latched onto the cube as the main building block of mathematics. For Fuller, the 90 degree angles of the cube were a side effect or "precessional effect" of various processes in a universe of angles, curves and arcs. His cube was inscribed by the duotet, two interpenetrating tetrahedra whose eight outer points met cube's eight vertices and gave it an inherent stability.