## Classical Design Method

If Vitruvius's accounts may be taken as an accurate indicator, classical design method comprised a variety of approaches. As already mentioned, geometrical schematization was employed to plot the location of the formulaic features of an amphitheater. By contrast, the proper juxtaposition of functions was the rationale for devising the spatial scheme of a house. And the formulation of a peripteral temple was based on an aesthetic code. Vitruvius did not cite design method as an explicit issue, but it lay at the heart of his instructions for these various building types, all three of which have conventional formats. Among the three, the one that remained relevant for the broader theory of architecture was that employed to design the peripteral temple.

For that purpose Vitruvius was preoccupied by the peristyle, the design of which emanated from the thickness of the column shaft at its base, taken to represent either a single or a double module. This module was employed in the spacing of the columns, determined by formulaic variations. The dimensions for the platform resulted from the total number of modules in the columns and inter-columniations. (Paradoxically, the configuration of the naos—the enclosed portion of the building that served the cult function of the temple—and its siting within the peristyle did not occupy his attention.) The module also determined the height of the columns and, in turn, influenced the height of the entablature. The total height of the order was coordinated with the total width of the temple and that, in turn, with the length. So the choice of a particular dimension for the module had ramifications for the entire design process. Although Vitruvius never discussed the rationale of the temple plan as a whole, an ideal image—a pedi-mented temple front—governed the design.

Once the basic composition had been determined, a whole series of refinements needed to be incorporated in order to ensure correction of optical distortions imposed by distance or restricted viewing conditions. Sometimes both the platform and the entablature were to be curved slightly upward in the middle of each of the four sides of a temple to avoid the illusion of sagging. If a column was unusually tall its taper needed to be curtailed to compensate for the impression of greater diminution over distance. So, likewise, the spread of the capital and the thickness of the architrave had to be proportionately increased. Columns set behind other columns needed to be thinner, but they ought to have more numerous flutes for the sake of suggesting greater thickness than they actually possessed. Tall columns on the long side of a temple must lean inward slightly on their outer face, but needed to be perpendicular to the platform on their inner face in order to make them appear straight. And finally, any proportions were to be adjusted according to the judgment of the eye when conditions of viewing imposed apparent distortions. (De architectura III.iii.11-13, III.iv.5, III.v.4, 8-9, IV.iv.2-3, VI.ii.4.)

The upshot of such a design method was that for any building based, however loosely, on the peripteral temple, the requirements of the columnar feature and its coordination with the main block dominated the procedure. However carefully the spaces of that block may have been composed in order to serve their respective purposes, their arrangement within the block and their dimensions would be affected by the limits imposed by the columnar order and the requirements of spatial proportion. Consequently, if the design of a building was rooted in the classical tradition, it was necessarily conditioned by an ideal image, one largely formulated from the outside in.

5 The Orders: Evolving Rules for Formal Beauty

For the centuries prior to Vitruvius, the absence of any surviving theoretical treatises leaves the evocative ruins of ancient temples as the sole evidence of their creators' aesthetic intentions. Hence the ideas that shaped the buildings may be discerned only by analyzing the evidence visible in the stones. Although a modern formal analysis may not fully represent Greek and Roman intentions, such an interpretation is based on incontrovertible data, which affect both the elements of the orders and their role in the overall composition. Such an analysis is worth making because it permits a meaningful distinction between Greek and Roman usage.

As the central concern of theory based on conventions, the lore of the orders is of the highest importance. Although at any given moment their formulation was subject to precise stipulations, the aesthetic concept governing the rules was continually evolving. For that reason, it is necessary to follow the course of that evolution, examining the key moments of its development.