By the early 20th century a preoccupation with the proper function of architectural ornament was characteristic of all advanced architectural thinkers, and by the mid-20th century a concept of architectural ornament had been formulated that has been called organic ornament. This concept, however, is by no means peculiar to the 20th century. Its essential principle is that ornament in architecture should derive directly from and be a function of the nature of the building and the materials used. This principle is characteristic of both Christian and Islamic religious architecture of the medieval period. In the architectural ornament of Muslim India or Persia, as in early Christian and Byzantine work, there is a strong mimetic element. The proscription of representational forms in the Qurʾān and the tendency of both Muslim and early Christian artists to borrow and adapt their formal vocabulary from preceding cultures led inevitably to their transforming what had been meaningful forms into systems of abstract ornament. But basically this ornament was neither mimetic nor applied. Throughout the Middle Ages, church buildings were conceived primarily as tangible symbols of heaven. Their architectural ornament, no matter how various or lavish, was consistently designed to promote this symbolism; whether by gilt, intricacy, or multiplicity, it all contributed to an overall effect of glory and so was integral to the architectural form.
Twentieth-century concepts of the function of architectural ornament, generally speaking, began with an understanding of this medieval usage that grew out of the 19th-century writings of the English art critic John Ruskin and the French Gothic Revival architect Viollet-le-Duc" class="md-crosslink">Eugène-Emmanuel Viollet-le-Duc, as well as through the interpretations and applications of the British designer William Morris. The immediate influence of these men proved rather unfortunate. The first result of Viollet-le-Duc’s disciplined and scholarly investigations into the principles of medieval architecture was a school of slick archaeological architects, capable of decorating all manner of collegiate, civic, and domestic buildings with frigidly correct reproductions of the details of medieval cathedrals and châteaus. Out of Ruskin’s demonstration of the origins of medieval decoration in natural forms there grew the so-called Art Nouveau movement toward exaggerated floral and curvilinear ornament, and out of Morris’s insistence on handicrafts, inspired by infatuation with the medieval guild system, developed the Arts and Crafts movement.
As early as the 1870s the U.S. architect H.H. Richardson adopted the Romanesque style, less for its historical associations than for the opportunities it afforded him to express the nature and texture of stone. In mature examples of his architecture from the mid-1880s, ornament in the older, applied sense had virtually disappeared, and his buildings depend for their aesthetic effect mainly on the inherent qualities of their materials. The generation following Richardson saw a further international development of this principle.
In Great Britain Sir Edwin Lutyens and Charles Rennie Mackintosh, in the Netherlands Hendrik Petrus Berlage, and in the United States Louis Sullivan were among many architects who contributed to the new ornamental expression. It was largely based on intrinsic texture and pattern but with interspersed bands and patches of naturalistic ornament, applied with studied discipline. With the general reaction against 19th-century eclectic principles of ornamentation after World War I, however, leading designers rejected even this kind of applied ornament and relied for ornamental effect on building materials alone. The so-called International Style, in which the German architect Walter Gropius and the Swiss-French architect Le Corbusier were the chief figures, dominated advanced design during the late 1920s and 1930s. The barrenness that resulted from their reliance on such materials as concrete and glass, however, along with other factors, resulted in a reaction in the 1940s in favour of the neglected precedent set by the U.S. architect Frank Lloyd Wright in his early 20th-century work, which emphasized more visually interesting materials, intricate textural patterns, and natural settings as the proper basis of architectural ornament. This trend continued in later decades; the style known as the New Brutalism was related to it. Alan Gowans Theory of architecture
The term theory of architecture was originally simply the accepted translation of the Latin term ratiocinatio as used by Vitruvius, a Roman architect-engineer of the 1st century ce, to differentiate intellectual from practical knowledge in architectural education, but it has come to signify the total basis for judging the merits of buildings or building projects. Such reasoned judgments are an essential part of the architectural creative process. A building can be designed only by a continuous creative, intellectual dialectic between imagination and reason in the mind of each creator.
A variety of interpretations has been given to the term architectural theory by those who have written or spoken on the topic in the past. Before 1750 every comprehensive treatise or published lecture course on architecture could appropriately be described as a textbook on architectural theory. But, after the changes associated with the Industrial Revolution, the amount of architectural knowledge that could be acquired only by academic study increased to the point where a complete synthesis became virtually impossible in a single volume.
The historical evolution of architectural theory is assessable mainly from manuscripts and published treatises, from critical essays and commentaries, and from the surviving buildings of every epoch. It is thus in no way a type of historical study that can reflect accurately the spirit of each age and in this respect is similar to the history of philosophy itself. Some architectural treatises were intended to publicize novel concepts rather than to state widely accepted ideals. The most idiosyncratic theories could (and often did) exert wide and sometimes beneficial influence, but the value of these influences is not necessarily related to the extent of this acceptance.
The analysis of surviving buildings provides guidance that requires great caution, since, apart from the impossibility of determining whether or not any particular group of buildings (intact or in ruins) constitutes a reliable sample of the era, any such analyses will usually depend on preliminary evaluations of merit and will be useless unless the extent to which the function, the structure, and the detailing envisaged by the original builders can be correctly re-established. Many erudite studies of antique theories are misleading because they rest on the assumption that the original character and appearance of fragmentary ancient Greek and Hellenistic architectural environments can be adequately deduced from verbal or graphic “reconstructions.” Even when buildings constructed before 1500 remain intact, the many textbooks dealing with antique and medieval theories of architecture seldom make qualitative distinctions and generally imply that all surviving antique and medieval buildings were good, if not absolutely perfect.
Nevertheless, the study of the history of architectural philosophy, like that of the history of general philosophy, not only teaches what past generations thought but can help individuals decide how they themselves should act and judge. For those desirous of establishing a viable theory of architecture for their own era, it is generally agreed that great stimulus can be found in studying historical evidence and in speculating on the ideals and achievements of those who created this evidence. Distinction between the history and theory of architecture