Writing about style in architecture, the nineteenth-century theorist Viollet-le-Duc asserted that "style consists in distinction of form," and complained that animals expressed this better than the human species. He felt that his contemporaries had "become strangers to those elemental and simple ideas of truth which lead architects to give style to their designs," and he found it "necessary to define the constituent elements of style, and, in doing so, to carefully avoid those equivocations, those high-sounding but senseless phrases, which have been repeated with all that profound respect which most people profess for that which they do not understand."
During the sixteenth and seventeenth centuries architects not only paid attention to internal arrangements, but subordinated the designs for the exterior to them. The usages of life dictated the arrangement and the arrangement suggested the form of the building. This was the dominant principle in times of Classical Antiquity and the Middle Ages.
it is apparent that the unfolding of the design process assumed a distinctly episodic structure, which we might characterize as a series of related skirmishes with various aspects of the problem at hand.
As the scope of the problem became more determined and finite for the designer, the episodic character of the process seems to have become less pronounced. During this period a systematic working out of issues and conditions took hold within the framework that had been established. This phenomenon is not at all surprising when we consider the fundamental difference between moments of problem solving when matters are poorly defined and those with clarity and sufficiency of structure.
Within the episodic structure of the process, the problem, as perceived by the designer, tends to fluctuate from being rather nebulous to being more specific and well-defined. Furthermore, moments of "blinding" followed by periods of backtracking take place, where blinding refers to conditions in which obvious connections between various considerations of importance go unrecognized by a designer.