After a brief introduction, Robin Evans proposes to discuss the relationship between geometry and architecture—a topic which may seem straightforward. He discusses the ideas that architecture requires geometry as its basis, and that geometry is a kind of unquestionable truth. He compares compositional geometry with projective geometry and discusses the mathematical extension of drawing through stereotomy. He also discusses the fourth dimension, cubism, and fragmentation. He discusses the Merzbau of Kurt Schwitters as interior design. He discusses the futurists and their relationship with Antonio Sant'Elia. Evens reflects on Sigfried Gideon's equation of the fragmented surface of the cubists to the highly reticulated, gridded and organized surface of modern architecture.