Our symbol, a tetrahedron, is a pyramid with a
triangular base. It represents stability. Four spheres pack into a
tetrahedron; tetrahedrons nesting together, 
advancing
in the most economical way: they fill our space and are the measure of our
experience.
Through his work with tetrahedrons, Buckminster Fuller shows us that architecture is about the economy and elegance of simple solutions to complex problems.