Proportion and Continuous Variation in Vitruvius’s De Architectura

Abstract

It is important to balance Vitruvius’s discussion of the architectural orders, centered on temples, with his sections on civil and, in particular, domestic architecture. It is in this domain, the subject of Book 6 (Chapters 3 and 4) of the De Architectura, that the relationships implied by the term symmetria appear explicitly, in both functional and aesthetic terms and without interference from the question of whether the recommended ratios are affected by the transformation of wooden temples to stone ones. Based on a review of his rules for designing atria, the Vitruvian conception of order as genus appears not as a fixed set of ideal relationships laid down once and for all, but as a series of variations in proportion. While certainly not obeying the concept of “function” as developed in the seventeenth century, these variations can nevertheless be shown to follow continuous curves interpolated from sets of derived values. In this respect, the Vitruvian project finds contemporary expression in today’s CAD/CAM software.