The teachings of the earliest technical treatises go beyond the apparently simplistic recipes they contain. Examples in such a context are merely a pretext for teaching the organic relationships of a form. The drawing or the text therefore surpasses the individuality of the object to be constructed. In this respect, the authors provide the means. They explain how to give the work the right proportions, "like a well-formed man", to use the expression dear to Vitruvius.
Analogical representation of construction, after Francesco di Giorgio Martini
From the viewpoint of the archetype, the keys of construction are given to us by two ways of expressing relationships: analogy and symmetry.