The author argues - in contrast to parts of established research - that Euclidean geometry, Pythagorean number theory, and Vitruvian modular theory have always formed the foundation of rational design in all high cultures for all sophisticated constructions, and have been preserved in the standardization of building components up to the present day. The second volume focuses on the period from 6500 to 456 AD and discusses, against the backdrop of the historical development of Greece and the Roman Empire, the modular design and proportion method of the Augustan architect Vitruvius. The basis of his teachings are the customary measurements, such as the imperial foot valid throughout the Roman Empire, and the basic dimensions derived from it.