1977 Harvard Publication Series

HARVARD GRADUATE SCHOOL OF DESIGN
PUBLICATION SERIES IN ARCHITECTURE

Alexander C. Tzonis and Liane LeFaivre
HISTORY OF DESIGN AS SOCIAL SCIENCE

A-7701
Paper presented at the Art History Institute, Utrecht, The Netherlands 16May 1977

History is returning to design. Disrespect for products of the past, indifference towards historical context, ignorance and negation of traditional forms and contempt for history courses in design schools, all tendencies of the modern designer, are coming to an end. Instead of destroying and subordinating inherited surroundings, architects are beginning to preoccupy themselves with integration and continuity. The faith in new projects is weakening, the concern for old environments getting stronger. Design elements and styles from the past are creeping into plans and history courses are finding favour in design schools once again. On a different scale and from different perspectives three stirring recent publications in design theory, the A Pattern Language (1968) of Christopher Alexander, The Mathematics of the Ideal Villa (1976) of Colin Rowe, the Teoria e Storia dell' Architettura (1968) by Manfredo Tafuri all rely on or address the past.
The causes for the reversal of attitude in design are numerous and complex -economic, social and ideological. The energy crisis, the recession, the emergence of ethnic pride and a general anxiety towards any form of innovation, given the practical failures of Modernist architecture and urbanism, are some of the .determinants of this revisionism. A thorough knowledge of the past is fundamental for preserving, conserving and designing inside the old fabric and within traditional visual.vocabularies as the work of Professor Fitch in the United States has shown and as the spectacular restoration projects in Poland and in the Soviet Union have demonstrated. Out purpose here is not to study the reasons for this situation or to analyze these immediate environmental strategies. It is to see how history can contribute to the study of a more fundamental problem which still remains unresolved, concerning the relationship between design and society, the meaning of design objects in terms of their social use and their social impact. The question is a long- standing one, but history has rarely been used to answer it.
Objects are not created in response to pure functional necessity, nor do they arise in the mind of the designer from an instinctual urge to create. They are the outcome of pre-existing conceptual frameworks whose structure is socially determined and whose aim is social. Buildings, cities, parks and transportation networks are products of design decisions. These are implemented or enforced through institutions. Ultimately, it is interests operating in society that support the conceptual frameworks and control the institutions. In the final analysis all uses of design are social, all serving to create, to maintain or to dissolve human dependencies. But the functions of conceptual frameworks, institutions and interests are not always readily visible. Neither is their long-term impact on human relations. Whether by intention or by accident, these workings may be lost or buried. No other discipline can retrieve them as well as history. Any study of the social use of design must focus on the interactions which connect, over time, interests, institutional structures, conceptual frameworks, design decisions, design products and human relations.

II
The interaction between human relations and design products seems to be the subject of extensive investigations in environmental psychology, ergonomics and cultural anthropology. The fact is that those studies in most cases do not analyze in depth the social use of design. The reason for this stems from the methodological constraints inherent in the methods adopted in those fields. They provide a narrow understanding of the relationship between design and society, relying as they do on the methods employed in the physical sciences. As engineers record the properties of materials by observing their behavior under certain conditions, so these social scientists observe the behavior of the users of the built environment in order to evaluate the design product. In this respect they continue the tradition of Locke by viewing all phenomena of the world as "materials" and of relying on "observation" to acquire knowledge. By grafting the concepts and principles of mechanics onto design, this approach concentrates too narrowly on the observable behavior of the user of the man-made environment and confuses description with explanation. By failing to take into account the dimension of time it divorces the products from the forces that generated them and isolates the behavior of the user from the overall context of human relations and of conditions which determine the system of rules within which the user perceives, chooses and acts.
This is not to say that empirical data have no value in the study of design. It suggests rather that, in this case, the data assembled and the model used for organizing them are not sufficient to yield significant conclusions about the social use of design. No amount of analytical manipulation of those data can redeem these faults.
Similar are the shortcomings of the study of the man-made environment as "habitat". This approach borrows: from the methodological and theoretical constructs of biology and ecology. It presents culture as an extrapolation of "animal tradition" differing from it "only in degree" (Wilson, 1975, p. 168) and design objects as extensions of the human body, products of individual needs of the human organism in its effort to adapt to its milieu, tools created by the interaction between the human physiology and the natural environment. Every time a new product appears, it alters the relation between man and environment since it modifies the existing environment. Thus, new man-environment interactions and conflicts emerge and new needs develop. The environment is in constant evolution because of the spin-off of previous products generated to meet anterior needs of man-environment conflicts.
(This vulgar materialist hypothesis has been frequently adopted by anthropologists. It was fundamental in supporting the "functionalism" of Malinowski. It was widely popularized through the writings of Gordon Childe and recently found a new vogue in the writing of ethologists and sociobiologists. For a critique of their works see Marshall Sahlins (1976). It was also to a great extent the implicit pre-supposition at the United Nations Habitat Conference in Vancouver in June 1976. One of the authors also adopted it in a previous book. See: S. Chermayeff and A. Tzonis, 1970).
These cybernetic-like models occasionally have impressive descriptive capabilities which can cope with development in time. But their explanatory power is weak. They too, like the social engineering and the behavioral sciences models, offer descriptions as explanations; although they do not exclude the dimension of time from their analysis of design, they ignore the social use of design products in the past, presupposing that humans and biological organisms operate similarly. They are unable to see design objects as part of an artificial world resulting from conceptual frameworks and institutions based on interests.
Neither the model of mechanics, nor the model of biology can be extended or applied by analogy to the domain of the man-made environment, because to understand how the man-made environment operates and how it affects human relations, requires a perspective which only history can provide.

III
Not every kind of history can explain design, however. An insular history, based on categories that ignore the original interests, concepts and institutions which determine the design decisions can only be limited, not to say misleading.
Such is the case, for example, with the architectural history developed by S. Gideon (1941) in' a tradition that reached back at least as far as Choisy and Viollet le Duc. The works of architecture of the past were perceived as springing from a primitive anticipation of the modern technology, the conspicuous search for new space and construction arrangements to demonstrate the novelty of construction techniques and materials and the legitimacy of their use. Gideon's criterion for appraising buildings of the past was the degree to which they appeared to conform to Modernist or Bauhaus tenets, as though the past of architecture was nothing but pre- history, a lengthy gestation period preceding the birth of the first fully rational, functional, or rather functionalist, design movement.
This arbitrary interpretation can be characterized, in the words of Voltaire, as a trick played by the living on the dead. Such thinking was a-historical both in its contempt for the reasoning behind the objects of the past and in its ignorance of their former uses. False, such interpretations also contributed to the environmental devastation caused by modern architecture by providing it with a historicist license to freely replace the old urban fabric with new structures.
A very different approach to history of design is that of the stylistic school. It perceived the designed products not as answers to functionalist problems but as aesthetic creations asking only to be looked at and appreciated.
(For an edifying discussion on the notion of style see Meyer Shapiro, "Style", in A.L. Kroeber (ed.), Anthropology Today, 1963.)
Early studies in this tradition endowed artistic creation with powers all its own. In order to account for the variety among design products, the amateurs of fine objects claimed that a style developed in cycles, that it "blossomed" and "withered" like a "plant". The cyclical theory of history, can be traced back as far as Plato's Laws. The broad application of this model tended to be open to idiosyncratic interpretation and conjecture (See Robert Nisbet, 1969). It characterized a period as high or low on the basis of vague criteria, and the reasons given for this fluctuation were rather facile.
For Winckelmann, one of the most prominent representatives' of the approach, the reason for the "decline" of Greek art was that its "images.. .had been formed in all conceivable shapes and attitudes and it had become increasingly difficult to think of new ones." (Winckelmann, 1764).
Heinrich Wölfflin is considered the leading opponent to the reaction to this cyclical model of history. He accused his predecessors of "never (having) systematically founded" their assumptions (1888). He undertook the creation of a sounder basis for the discussion on art, a kind of categorical framework, analogous to the one Kant developed in philosophy through his priori categories. Wölfflin postulated that changes in style came in succession and "they oscillated in an orderly way, between opposite "forms of vision", which were the following: linear versus painterly, parallel surface versus diagonal depth, closed versus open, composite versus fused, clear versus unclear. "Art history," Wölfflin stressed,"is more than a 'translation of life' (Taine) into pictorial terms... which attempts to interpret every style as an expression of the prevailing mood of the age... the moment we want' to apply artistics standards of judgement in the criticism of works of art we are forced to try to comprehend formal elements which are unmeaning and inexpressible in themselves and which are developments of a purely optical kind".
(Wölfflin, 1898, italics
Wölfflin's investigation of history through abstract categories of pure visibility presupposed that the purpose of a design object was to create a visual aesthetic impact. It also rested on the assumption that such categories were universal. From this it followed that the visual properties of the object, its stylistic traits, fully expressed its meaning. consequently only !formal factors were incorporated into the analysis. Moral, religious, philosophical and political significations were abstracted, as were emotion and technique.
Alois Reigl proposed a method of historical analysis based on an a priori structure similar to Wölfflin's in that it also included a list of alternating abstract visual polarities. The categories themselves, however, were different: tactile versus visual, the presentation of the object isolated versus being placed in space, objective versus subjective (1901, 1907).
Although Riegl tried to develop a universal set of abstract categories, his analytical tools were still, like Wölfflin's, bound to the objects at which he aimed his analysis, those of the Ancient Near East, and of the Roman and Early Christian periods. Moreover, Riegl based his analysis on the same assumptions as Wölfflin: that the purpose of design objects was to create a visual aesthetic impact. To explain the creation of design objects, he developed the concept of Kunstwollen following the theory of Schopenhauer that every human action is the product of forces, that every art relates to a will and that every stage of every art corresponds to an advancement of will. To explain how visual characteristics changed in time, Riegl asserted that periodical changes in style were the result of the pulse of the mentality of the time, what he called the "Denkweise".
Whereas Wölfflin's and Riegl's stylistic analyses relied on formal aspects versus the content-bound or emotional characteristics of visual elements, Theodor Lipps (1907) and later his follower, Wilhelm Worringer, (1908), stressed the opposite: expression and emotion. Forms had an impact on the viewer, they claimed, because he recognized in them the expression of feelings, because he himself became incorporated in the forms or because "he unconsciously, (felt) inwardly the process of their formation". Forms were the outlet of "inner feelings", "the expression of spiritual unrest", "the liberation of (a) sense of vitality" (Worringer, 1927). Departing from the same suppositions as Wölfflin and Riegl and under the same influence of Schopenhauer about the aesthetic purpose of design products, Worringer stressed that while "the will to form remained the same throughout the entire development", the differences in style were the results of an interaction between "stages" in feelings, in excitement, in pathos which dominated man in a period, and the kinds of material available which permitted the expression of those feelings through works of art.
The approach of the stylistic analysis of the history of design had two basic limitations. The first was that although the methods strived to be universally applicable, they always remained bound to the set of objects from whose observation they emerged. As historians shifted their focus to new areas, the accepted stylistic categories met with operational difficulties for they could not account, even as criteria for classification, for all periods and places. New categories had to be advanced always in keeping with the presupposition that the purpose of a design object was to foster a pure, abstract visual aesthetic impact. Which brings us to the second limitation of this approach to design history: its failure to identify the actual use of the design object in a given period and to explain the general phenomenon of the production of the man-made environment. This failure stemmed out of the inability of the field to overcome the boundaries of its original program defining the role of the design historian as an assistant to the amateur and the collector.
The historian of design was curator, connoisseur and author of catalogues raisonnes in which visual characteristics helped to date, to assign origin, to determine authenticity, to label and to appraise works of art. At the beginning of the 19th century connoisseurship split into archaeology and art criticism. The archaeologist, and we refer here to the museum expert utilizing the lesson of philology, developed techniques and identified attributes for constructing taxonomies of design products of the past with little concern for the tastes and preferences of his day and for the value of the obj ects as a collector's item. As a result, the archaeology of the last century, the new scientific connoisseurship became a discipline as organized and challenging as that of minerology or botany and equally indifferent to the problem of explaining the objects described and classified.
The design historian-critic also developed categories for classification. But the urge to evaluate was always present in his analysis. For this reason his categories were dominated by contemporary aesthetics, by a concern for the creation of new products, and they reflected the taste of the day rather than the thinking of the past. Winckelmann's categories were closely linked to the Neoclassical movement, Ruskin's to the Pre-Raphaelites, Wölfflin's to the movement towards abstraction and Worringer's to expressionism.
The concern for evaluation was not without consequences. As Marc Bloch so sharply pointed out, "The habit of passing judgements leads to a loss of taste for explanations"(1953). And this holds true however broad the criteria of evaluation.
James Ackerman, in a recent effort (1974) to revitalize architectural historical criticism by enriching its criteria of evaluation, warned that. "a criticism that avoids the issue of "moral option" simply fails to account for the actual nature of the transactions involved in designing buildings". Ackerman is deeply disturbed by the weakness in historical criticism "of the assessment of a choice" based on any "irrelevant" anachronistic values, even when those Values are moral.
In an earlier paper (1949) he demonstrated its failures in relation to Gothic Architecture. The recent paper also continues this criticism. Yet the references to moral values are ambiguous. The ambiguity lies in that the introduction of a moral point of view brings to the history of design not only a strong, explanatory, analytic framework, that of human relations, but also an evaluative one. Because, as stylistic analysis presupposes that design products ought to have an aesthetic visual impact, the moral point of view recommends a certain state of human affairs. In both cases the presuppositions may be irrelevant to the period under discussion which suggest that the acceptance of the task of evaluating, of "criticizing" past design products by the design historian, may be invalid unless a universal standard of evaluation is proven to exist. This holds true for stylistic or moral criticism.
In order to analyze in depth the design process involved in the production of the eastern facade of the Louvre during the reign of Louis XIV, for example, one must explore it in the context of the external conflicts of the absolutist regime and of the internal conflicts and coalitions that involved the nobility, the court, the mercantile class, the guilds and the peasantry. To appraise the actions of any of these groups as morally good or bad impedes any further explanation of the social relations, events or objects in question. An evaluation of this type is not very different from measuring the design of the Louvre in terms of any other evaluative standard, such as meeting the specifications of structural efficiency, of economic construction or of micro-climatic control, of the compositional criteria of the Beaux Arts, or of Marcel Duchamp, of the ideals of the socialist revolution, or of humane values with respect to the small number of workers it mobilized. This can be an absorbing type of exercise, but it can hardly inform us as to why the Louvre was designed the way it was and what its erection meant to the contemporary society. By getting involved with evaluations of past products, historians of design have committed the fallacy classified by David Fisher (1970) as false analogy. They have looked at the decisions, the actions and the products of the past as answers to questions of the present. To borrow from a similar criticism, which Collingwood (1939) made of the anachronistic "realist" attitude of his colleagues in philosophy, it is like objecting to the poor descriptions of steamers by the ancient Greek authors who, in fact, were referring to triremes.

IV
In his intriguing essay on Gothic Architecture, Erwin Panofsky (1951) did try to develop an analysis of design, free of the evaluating predisposition of historical criticism. He compared the dominant scholastic writings of the period with the cathedrals, the "new style of building" (p. 4). He found a correspondence between the theological argumentation in the texts and the architectural elements. Because the structures of both presented a similar development, he concluded that the modes of thinking and the habits of designing were shaped in a similar manner.
But the essay of the Gothic Architecture departed from the false presupposition that design products are of the same nature as thoughts. For this reason its conclusions are much more limited despite the fact that the material brought together, as a result of Panofsky's formidable erudition, is bountiful and the pattern of correspondences, striking. But those elements are not enough to lead to a conclusion if the presuppositions behind them are invalid. Panofsky warned the reader from the outset about the pitfalls and the hazards of the pursuit of such "parallels," but he was unable himself to resist the temptation of drawing inferences about "palpable and hardly accidental concurrence" from such analogies when he confronted them. As a result the "unities" he established between design products have at their best a classificatory value and the essay fails to provide an historical explanation for the genesis of form which was true to the period.
Efforts to establish analogies between texts and design products of the same period, can be found related to content rather than formal characteristics. Those studies see texts and buildings as expressions of a common spirit of the epoch, a common world view. A typical example of this approach to history of design can be found in Pevsners's analysis of Renaissance architecture (1943).
"Architecture is not the product of materials and purposes - nor by the way of social conditions - but of changing spirits of changing ages. It is the spirit of an age that pervades its social life... The Gothic style was not created because somebody invented rib-vaulting, (it was) worked out because a new spirit required it". (1943 p. 17)
Departing from such assumptions, Pevsner arrived at the speculative conclusion that the "central plan" of the Renaissance church was "the symbol of worldliness" and of "the spirit of Humanism." In fact, as other studies factually demonstrated, to express the spirit of an epoch is a use of architecture not applicable either for the Renaissance or for the Gothic.
To study such anachronistic histories of design may be interesting and rewarding. Some designers may find. stimulation in them for expanding their formal vocabulary. This is the purpose of a large number of courses in the history of architecture in schools around the world. One may also profit from the excellence of expression and the organization of ideas that these histories exhibit. In addition, these histories, as little as they explain about the objects they look at, reveal much about the times in which they were themselves written. Because such histories, in the words of Marc Bloch, are as if holding "a mirror in which the collective consciousness surveys its own features."
In committing the historical error of prejudicing their analysis in advance, they are very much like those "German soldiers in 1914" who "envisioned... as so many loopholes prepared for snipers...the innocent contrivances of the masons...on the fronts of a great many Belgian houses.. which were only "designed to help the plasterers in setting up their scaffolding" (1953).
In the end, the findings of the stylistic analysis and the conjectures about the formal expression of the spirit of the time can be applied only to those works which have been conceived as stylistic compositions or as expressive statements of a period. Visual uniformities do form clusters at certain locations in space and certain periods in time, but such phenomena do not always arise from stylistic considerations and cannot always be explained through stylistic categories. To understand a design product, one must find the document that reveals its meaning, its real use.

V.
There is a telling anecdote about how unsuspected documents can shed light on the meaning of objects. In one of his most vivid passages, Emile Male (1945) recounts his chance discovery of Cesare Ripa's Iconologia (1603) and, therein, of the key to Bernini's personification of Truth in the Villa Borghese and to much of the 17th century's allegorical representation. Referring to a group of Lebrun's statues in the garden of Versailles he wrote:
"Jamais, je l'avoue, je n'avais cherche a savoir de que representaient les statues du parc et je pense que la plupart des promeneurs n'ont pas plus de curiosite. On ne songe pas a demander leurs noms a ces figures blanches..." (p. 205).
Ripa's Iconologia is not unique. A large number of documents is to be found where meaning is matched with the design of physical objects, one of the most ambitious ones being Emanuel Tesauro's Il Cannocchiale Aristotelico (1670). Borrowing concepts from Aristotle Tesauro tried to build a general system to describe and prescribe the total artificial world as a universe of objects which are meant as carriers of meanings, as words of a discourse or, as it was called in the 17th century, an "Argutezza." All objects, whether "Natural Bodies" (Corpi Naturali) or "Artificial Bodies" (Corpi Artificiali), were seen as "Rhetorical Images" (Imagini Rettoriche), as "names" and "oracles", and all compositions with those objects, as "sentences" (sentenze Argute) in a "language" (Parola) subject to "interpretation". Design was seen as a process of coding. It is only with this conception of the man-made environment in mind, that is as a symbolic universe, that history of design can be envisaged as an activity of decoding.
This is the dominant direction taken by the Warburg Institute under the guidance and inspiration of Aby Warburg. In the first issue of the Journal of the Institute (1937- 1938) Jacques Maritain sketched a program for the study of culture and its development through a "study of signs and symbols." The work at the Institute echoed a similar contemporary program set up by Ernst Cassirer (1921) to interpret and analyze culture viewed exclusively as composed of "symbolic forms ," a "system of signs", a "world of symbols."
Recent attempts to reduce history of design to a history of signs and codes or to a history of relationships between the so called signifier and signified (Schaeffer, Jenks, Ch. and Baird, G. 1969) should be seen as a generalization of previous efforts of the iconological approach. This direction, under the name of semiology (Barthes, R. 1964, Eco, U.) having been influenced substantially by Saussurian linguistics (Saussure, F. 1915), extended iconological analysis with the notion of syntax, grammar and other morphological characteristics of language in addition to meaning. But a history of design based exclusively on iconological documents and semiological consideration, although applicable to certain works, has its own limitations. It can relate only to products that have been constructed as symbolic objects, as discourses, as purveyors of menages that have been derived from a process of coding and whose only purpose is to signify.
In the development of culture, a large number of man-made objects are made simply in order to carry a meaning. A factory, an airport, a region organized, a camp, a bastion by Vauban or the projects for the new Hotel Dieu by Petit, Le Roy, Condorcet and other members of the Academie des Sciences just before the French revolution, and, in general, machines or instruments derive from decisions and conceptual systems which are not to be found in manuals of iconology or any coding system. The decisions that shaped them and the objectives inside those decipions, destined them not for signification, but for the production of utilities.
One ought to be careful not to confuse the case of a machine or an instrument when used as a symbol, as a signifier when it is represented in a painting or placed as an objet trouve on a podium in a gallery, with the case of the same machine or instrument which performs productive operations. Similar confusions can arise when a machine comes to signify the social or economic position of its possessor in addition to fulfilling its role as a producer of utilities. Neither of these signifying functions deter from the fact that machines and instruments can be made to produce exclusively energy, information, and not significations. A similar argument can be built, although too long and complex to develop here, to demonstrate that ritual props of archaic societies, the tattoos, the churingas, the shrines, are not pure signifiers but they stand between signifiers and machines as ancestors to both, and from both different.
From all that has been said about the limitations of the stylistic, iconological and semiological approaches, we have to recall the remark Wölfflin made in 1888: "We still have to find the path that leads from the cell of the scholar to the mason's yard." It appears that a more universal history of design is needed in order to accommodate the totality of design products -the machines, the objects of divination, the aesthetic objects and the icons. A broader range of documents must be explored, no matter what the type of thinking it reveals and regardless of the use of the object it relates to.

VI.
Studies of the past thirty years have uncovered a vast number of diverse documents which prescribe design decisions which link products with the thinking that generated them. Among these stand the remarkable pioneering work carried on by Rudolf Wittkower (1949). Wittkower reconstructed the conceptual system that actually determined design decisions and design products of Renaissance architecture, thus succeeding in establishing a secure bridge between the sources of the period and design objects. He found that the reasoning behind the creation of a work could not be reconstructed intuitively from the forms of the work itself, nor from the general theoretical writings of the time. One had to search in the very writings that pertained directly to design decisions and that other historians had failed to explore in depth or had completely bypassed.
In the words of Emil Kauffman, an historian who tried to analyze 17th and 18th century achitecture with an approach similar to Witkower's, "Architectural treatises need not be dry and dull. On the contrary, one may fund pulsing excitement..." (1944). The excitement springs out of discovering there the decisions which have generated projects and the systems of justification which have made decisions acceptable in the creation of the artificial world. These are the writings that reveal, or at least suggest, the path leading from the thinking of a period of its architectural products.
To summarize what we have tried to demonstrate up to this point, we can never claim to have understood a design object, let alone to have properly evaluated it, until we have, as Collingwood (1939) has said referring to philosophical systems, "reconstruct(ed) the problem," until we have "with the utmost possible accuracy" found the questions to which this object was meant as an "answer." Design products, like philosophical system, are "answers" given to "questions set by a given society at a first moment." The first step towards such a reconstruction is to find the discourse within which the question was posed at a given moment and to establish a secure bridge between a design product and the thought which led to its creation.
Without such a reconstruction it is impossible to understand the design object in particular, or the phenomenon of design in general. A product of a period cannot be analyzed through the framework of another period, because the two frameworks are "incommensurable" (Derek L. Philips, 1975). To use the expression of Ludwig Wittgenstein (1958), a different game is played in each case. This is why stylistic categories are only applicable to the analysis of works which have been conceived within the framework of stylistic rules and why iconological readings can be made only for objects that have been devised as "pictures" or "narrations." This is also why expressions such as "cartesian gardens" or "the cartesian urbanism" of Le Corbusier make entertaining metaphors or effectual slogans but lead to erroneous conclusions about the use and meaning of those objects.
The error lies in inferring that there is a similar thinking and similar intentions behind all the objects which share the same shapes. They are clustered together and they are associated with the same meaning because of an incidental property. It would be more proper in the particular case of "cartesianess" to speak of "cartesian" microscopes and "cartesian" guns, "cartesian" fortifications and "cartesian" hospitals as these objects were processed within a conceptual framework where the "cartesian" method and the "geometrical thinking" of Descartes did playa role.
For that matter, the cartesian method and thinking had little bearing either in the 17th century formal gardens (Tzonis, A. and Lefaivre, L. 1977) or in the urbanism of Le Corbusier.
The careful investigation of the discourse of a period may establish striking homologies and similarities between design products.
What historians of design, such as Wittkower and Kaufmann tried to do was to link, in a reliable way, the development of design products with the evolution of thinking. This approach can be said to have bridged the gap between the history of design and the history of ideas. through a close comparative investigation of written documents and built forms. This secure bridge, however, may not lead all the way to a complete understanding of the decisions that govern production of the man-made environment. The history of ideas, and this holds true for the branch that interlocked with design history, has been criticized for discriminating in the selection of documents for investigation. The limitation we refer to now is no longer related to the type of document (iconological versus engineering discourses, etc.) but to the "social status" of the document, to the preference of "highbrow" over "lowbrow" documents, to the overlooking of notes and memos by humble technicians, of letters and diary pages by anonymous users or observers, to the seeking of the exclusive company of the writings in prestigious, expensively bound, elaborately printed and highly theoretical dissertations and treatises.

VII
But even when the data assembled reflect a "pluralistic" or "egalitarian" attitude to culture and society (Mandrou, R. 1961, 1972, Thomas K. 1971), still the account of the reasons behind the production of the man-made environment may be incomplete. The careful investigation of the discourse of a period may establish striking homologies and similarities between design products. Those conclusions may either "confirm" what the eye of the investigator had already "intuitively" depicted, thus explaining those patterns and making them more understandable, or they may reveal the existence of relations which had been "counter- intuitive". The reasons behind these common patterns are identified through the analysis of the discourse, and not merely premised by reference to vague or anachronistic theories about the growth and exhaustion of forms, the spirit of the times or the material conditions.
The enigmatic correspondences between the development of the alphabets of the Renaissance (Meiss, M. 1957) and of the gardens and buildings of the period, the intriguing echoes between the facades of its buildings or between every element in those facades, can be traced to the same pool of discourses nurturing common assumptions about shape and proportion (Hersey, G. 1976), common theories about the ideal human body and its use as a model and a common conceptual system, all connected by long chains of argumentation.
Discourses can also be used to disclose deep affinities between objects which appear different to the investigator, such as an Indian homestead and a Byzantine palace both being homologous, sharing common elements, in terms of the conceptual system which lie behind the design decisions.
But texts are not always explicit in revealing the norms, the accepted facts, in general the conceptual rules and constraints within which the decision-making process of design has taken place. Various components of the process act implicitly. They are presupposed or inferred. For this reason discourse analysis has had to develop systema- tic techniques (Robin. R. 1973, Tzonis, A. et aI, 1975) whose assistance in history of ideas and in design history is as indispensable as philological analysis was in the past.
Yet tools of discourse analysis are not omnipotent. There are cases where the discrepancy between what is stated in a text and what has really taken place in the decision-making process is so serious that no discourse analysis technique suffices to overcome the gap. This is when parts of the thinking are withheld, disguised or replaced in the explicit argumentation by a "dummy" warrant and when real causes and interests behind a decision stay well-covered and out of sight. Under those circumstances, the positivist standard, stating that the association between the discourse containing the design decision and the product of the decision must be observable, renders the reason for the object inaccessible.
This is frequently the case with the so-called "common sense" or "practical" discourses, with manuals, primers, handbooks, various types of technical abecedaries, or everyday discussions of the craft. Here justifications for design decisions are abbreviated, curtailed, condensed. These discourses are remnants from more elaborate justification discourses that have been incorporated at a previous moment by the mass of society, and that have come to operate in a quasi-automatic way. The operation gives the illusion of a "practical" decision-making in design existing independently from the "theoretical" one, of a design where the justification is "real" and where so-called "ideals" are not needed too support it. But a more careful analysis reveals that in fact there are no ways of designing which are more "common sense" or less theoretical. There are only periods where a "briefer" decision-making process is presented, with fewer justification steps and less complete explanations. These are the periods where higher norms and epistemological foundations, usually referred to as theory, have been instilled into the minds of the members of a society by agreement or by cooptation; periods where theory is no longer stated or debated; where trust or obedience eliminate the elaborations of a coneptual system - periods which are unquestionably less critical and more action oriented.
There are also periods to be found in design history when the acceptability of highest assumptions is questioned, when norms, facts or procedures in the decision-making process, which until this time had been taken for granted, had been honored or presupposed are now opened to scrutiny, brought to public debate.. Those are periods of crisis, of rupture and clash. But those are also the years when "practitioners" turn into "philosophers" and "amateurs" become "professionals ," when Alberti, a lawyer, or Perrault, a doctor, shapes forms with the same ease or decisiveness as they layout arguments.
In most of those cases of incomplete, fragmented and implicit argumentation in the decision-making process of design, discours,e analysis no matter how carefully carried out, if undertaken without any safe grounding in the soil that nurtured those discourses, can only be very restrictive or even misleading in terms of its explanatory power. An example of such a limitation can be found in the meticulous studies on Laugier and Perrault by W. Herrmann (1962, 1973) where neither the framework of absolutist institutions nor the mercantile and manufacturing interests were investigated.

IX.
The history of design discourses, then, must be complemented with a history of the institutions and of the interests of which discourses are only the voice. The history of design requires the investigation of the development of the complex of interests, of institutions, of conceptual systems, of design products and of the uses that the products are put to. The components of this complex are not linked to each other in a simple, deterministic way. Neither do they form clear, distinct fronts in time. They seem to have a life of their own.
Conceptual systems and institutions are to a certain degree made to operate independently from partial interests and from temporary situations. As a result of this relative autonomy, they come to be seen as eternal, universal systems, to be accepted, to be trusted, as though they represented the general interest and the collective will at every moment. In this manner they become legitimate.
Because of this autonomy, concepts and arguments may outgrow and outlive the initial reasons for which they were created. Justifications, theories, myths, related to actions which are no longer performed or not yet fostered, may still keep a hold on the mind. Institutions, professions, schools, once delegated for a certain task, may continue to operate well after the interests that gave them birth have died, just as they may take directions unforeseen at the moment of their inception. Conceptual systems and institutions may also appear to have a complete life of their own when new interests, which find their way into society and they may have to build on pre-existing conceptual and institutional structures (just as they have to perform on a given geomorphological terrain and in a given climatic milieu).
For example, the archaic, initially theological, concepts of beauty, love, harmony, rationality and force survived way into the modern world because they were taken over by the merchant and the artist of the Renaissance and used in a completely different, new framework: that of aesthetics and engineering as the monumental works of Leo Spitzer (1963) and Pierre Duhem (1906-1913, 1905-1906) have respectively demonstrated. One can also refer to the long journey through the centuries of the so-called Euclidean elementary shapes of the circle and the square, appearing now in the Italian Renaissance gardens, buildings and cities, now in the formal French gardens and the academic complexes of the late 17th century, now in the paintings of Cezanne, the buildings of Le Corbusier or of Isozaki, and now in the design of instruments and machines, observatories and fortifications. In each of these works the user of the design product and the interests are radically different. Continuity and permanence result from an inventive adoption which puts the same shape to a new use.
One can cite the endurance of building types such as the atrium or of building elements such as portico. They entertain the same autonomy as concepts do. They are put to different uses, they undergo changes in name and meaning, but the shell of the form remains invariant just as in the case of institutions where the old shelter may harbor new thinking, new activities or new interests. Such is the case of the institution of the Italian Academies versus the Academies Royales towards the end of the 18th century, the institution of the profession of the engineer in the end of the 16th century versus the beginning of the 20th century.
But such phenomena of "long duration", to refer to the term of Braudel (1958) do not reflect a _complete autonomy of the institutions, of the ,conceptual systems, of the production of design objects and of the interests. They point, rather, to characteristics of inertia, resistance, independence, indeterminacy and complexity present in the design process that have to be taken into account. They make design history more difficult but by the same count m~re exciting, challenging and needed.
The difficulties involved in analyzing these continuities and in identifying non-apparent connections have frustrated some historians to the point where they have claimed (as John Summerson did in his May 21st, 1957 R.I.B.A. lecture) "that the actual relationship of architectural theory to architectural production at any given time is problematic.." and concluded that "theory...is a historical process with a life of its own in its own medium of words and that there is no question either of principles being abstracted wholly from practice or of practice being necessarily a reflection of theory. "
A rushed analysis which does not take into consideration the complexity of phenomena of autonomy and long duration and adaption is as limited, from the explanatory point of view, as any other historical study which ignores altogether the conceptual, institutional and social reality of design. In its eagerness to make neat packages out of interests, institutions, conceptual systems and design products it forces them into associations and fronts, such as ones found in High Trevor-Roper's Princes and Artists, an analysis of the Escorial, and in other recent, "socially-oriented" work in architectural history.

X.
The choice of a method for addressing the past, which includes the selection .of the categories of analysis and the presuppositions which define those categories, constrains what history of design can yield, how much it can grasp, how deep its explanation can be.
The explanatory power of a method, its capacity to make design phenomena understood, is one of the two criteria
in the selection of a method, the second being the use of the conclusions of the investigation towards a social goal.
Up to this point we have argued that history of design must avoid anachronistic concepts in its method of analysis, concepts which are prone to "criticism" and that its goal should not be the evaluation of past products but their understanding. Furthermore we have argued that we cannot fully understand the nature of the production of the man- made environment unless we examine the relation between the design process, human relations and interests. We will now show that this critique derives both from the criterion of the explanatory power of a method and of its social contribution.
The broadening of design history to include the social use of design and the impact of design on society cannot be said to result exclusively from an abstract thirst for true knowledge. As Nelson Goodman has remarked, scientific results, "however true, are worthless. ..unless they raise or answer significant questions" (1968, p.263). The significance of questions, to quote Habermas (1971) is defined according to a norm which relates "knowledge and interest" (Habermas, 1971, p.311).
Stephen Toulmin (1972) and Thomas Kuhn (1970), from the Istandpoint of history of science, have pointed to the dependence of science of factors "exogenous" to the commitment to truth. The criteria of "social cost" and of "operating cost" which have been identified by Karl Deutsch. as being of major importance in the selection of a method of organising data (1966) direct us to the same issue although seen from a different angle, that of cost.
The admittance of such criteria that are exogenous to the search for truth in the workings of science does not imply that any of the supporters of this position would accept false data in a scientific investigation in the name of other imperatives. What has been referred to as valid in science is also valid in history of design. The notions, therefore, of rise and fall cycles, of style, of world view, of aesthetic, utilitarian or expressive missions of design - notions taken as universally intrinsic to the design activity, adopted in design history and criticism ~ are highly questionable for bringing false data with their methodological presuppositions. After having said that values and critical outlooks do enter into scientific endeavor we have to add that, in the case of history of design, they have been introduced on the levels of the design product, too soon and on too Iowa level as a consequence distorting the factuality of the data. Thus the results of design history frequently appear as biased as a so-called propagandistic discourse.
The screening of data to be analyzed in a scientific inquiry, including the history of design, hinges on an expectation of "relevant" answers, on a certain commitment to inferring them and on an interest in their contents. "Truth is not enough; it is at most a necessary condition" in this process (Goodman, 1968). The commitment to "relevance," which complements the criterion of truth, is a norm socially determined that guides scientific inquiry through the maze of all existing data and of all their possible combinations and leads it to the great avenues of theory and discovery. Therefore, history of design, as long as it is considered part of scientific inquiry, depends on social imperatives and on interests for its method. As the practice of design finds its validation and legitimation in society so do the methods for the investigation of design.
Most of the methods of design history that we have referred to until now employ anachronistic categories in their analysis of the objects of the past, and all share the belief that their categories are autonomous, owing nothing to the time and circumstance of their birth. The history of design may be built out of fragments of the past, but its function is not always to house memory. Often it obstructs from view former events and casts a shadow on their traces in the present. By using rapid generalizations and emotional evocations it makes the present world order appear more universally accepted than it always has been and presents it as a permanent state of nature and arising from deeply rooted human needs. The norms that tell what must be done, the categories and classifications that tell us-what can be done, and the institutions that serve these norms ~ classifications may appear as relating to a state of nature, as resulting from deeply rooted, unchanging human needs. In fact, they are bound to time, physical environment, state of social and economic development, conceptual frameworks, institutional structures and partial interests. There is always a moment when these new constructs are invented and a moment when they are put into operation. There events, clearly demarkable in time, follow from the adoption of new interests, collective or partial, to govern society and they may occur after the subjugation of one tribe by another, after the emancipation of a clan from its dependencies or after a new course of action against nature has been opened up.
That conceptual frameworks are artificial and deliberately created, that their adoption is related to interests, is sealed in silence. The resulting social amnesia contributes to an unconscious allegiance to these- interests. This may explain why the autonomy of the tools of historical analysis and the use of anachronistic categories, so limiting to the work of design history, from the explanatory point of view, were acceptable in terms of their social implications, helping to achieve consensus.
Together with history, professional activities, everyday exercise of common sense, the practice of standardization and imitation facilitate the incorporation of a state of affairs. This incorporation gradually buries the conditions which created and imposed those presupposed norms, and facts; those conceptual systems and institutions. It effaces the coercion and the cooptation which may have taken place at the moment when a new world order was established redefining what is valid and what is legitimate.
As physical barriers control human action, so do intellectual and institutional structures. Formidable walls, gates and turrets confine man, prohibit associations, channel movement, maintain slavery or any other type of dependence. Equally powerful are the invisible controls of ;:.he presupposed norms and facts of the incorporated conceptual systems and institutions. They guard, prohibit, and oblige us by imposing fear and by awakening desires. They form what we come to perceive as universal, unalienable human needs. What we see as a need for privacy, a need for variety, a need for territory, a need for view, a need to be satisfied by the order of geometrical facades, by the hierarchies of vanishing perspectives, by the complexity of ornamentations or by the intricacy of detail, which historians as well as designers frequently take for granted, are the outcome of historical conditions and processes.
As Wilhelm Dilthey has said, "what man is, only his history tells" (K. Klubach, 1956). In this he saw an undefeatable oppressive power, a fate to surrender to.
But history can lead to a different view of the past. As psychoanalysis can foster an understanding of the nature of the structures that control the decisions and actions of individuals by tracing back the origins of those structures in time, so history can promote understanding for whole societies. History goes beyond psychoanalysis because of its scope. It can question the legitimacy of the established conceptual frameworks and institutions which limit and channel actions, which impose a way of looking at the world. History dissipates the collective amnesia as a result of which concepts, practices, rules and beliefs may appear inexplicable, isolated, autonomous, static facts that carry no relation to human interests and to the structure of power. No other study of society can take its place in such investigations. To refer to Collingwood "the science of human affairs (is) history" (1939, p. 115).
Wöllflin saw in the creation of a "history of vision" a "necessary tool for the historical disciplines," as important as "sight itself." The history of the production of artificial objects, or of architecture in the broad sense in which it was used prior to the 19th century can provide a key to the understanding of human relations. A rigorous analysis of the design objects of the past, the investigation of the original conceptual frameworks within which these objects were conceived, produced and employed, of the institutions and of the socio-economic order which is associated with the design process, can yield more than an analysis of the objects themselves or an analysis of the behavior of the user of the man-made environment cut out from the context of the rules which determine this behavior.
The history of the man-made environment must study the meaning of the design objects at the time of their inception, the use they are put to and the controls they impose, physical or intellectual.
It must isolate or reconstruct the decision-making process, the kinds of arguments, the higher standing norms and data; in general, the conceptual systems which generate a product and which make the production of design acceptable, valid; it must also chart the genesis, the disappearance of the conceptual system and their components, the transfers influences, dependencies existing between conceptual systems
Then, it must identify and investigate the structure and operations of the institutions in time and see how they generated, housed, perpetuated and diffused those conceptual validating systems.
It must identify and study the development, the structure and the operations of the institutions that housed, perpetuated and diffused conceptual systems and it must investigate the interrelations among institutions.
It must research the interests of social groups and classes, in supplying support to the institutions (instrumental in the promoting of conceptual systems which produce the man-made environment) and the interactions of interests among social groups and classes. The choice of period is very important in this historical inquiry. The moments of transition from one conceptual system to another, of the collapse of an institutional framework and of the erection of a new one, the clashes between old and new interests may yield the most fruitful results concerning the deep under- standing of how the present has come about. Patterns of discontinuity and genesis must be studied as must those of continuity, resistance, retardation, reuse and adaptation.
Thus, history of design should focus, aside from the physical reality of products, on the social and psychological processes of control, decision, validation and legitimation which aid or impede the transfer of power into nodes of ever increasing tightness.
It should also open up its field of investigation to include a wider range of artificial objects. History of design, especially the branch defined after the presuppositions of the stylistic analysis, has traditionally focused rather narrowly on objects that were significant from the point of view of innovation, uniqueness and influences in their visual formulae. As Pevsner had once recommended, it confined it- self to "Architecture" versus "simple" building. The need now is to develop a history of" the objects of the artifical world in the total sense that includes the man-made landscape, the transportation systems, the urban fabric, the buildings, the everyday objects. The products to be studied must be selected with priority given to those which are significant from the point of view of their impact on human relations.
Buildings which have an aesthetic meaning may be as important to be studied as buildings which have none, such as ordinary buildings, buildings for public uses, for famous patrons, or for deviants. A design product may be selected because of its direct impact on other products or because it helped to develop a new conceptual system, a new institution, a budding interest which subsequently had an impact on human relations. Already a significant number of young historians are moving towards an in-depth study of such "ordinary" objects (Fortier, B. 1975, 1976, Boudon, F. 1975, Foucault, M. 1975, Evans, R. 1971, Hayden, D. 1976).
It is obvious that such studies in the history of the man-made environment must also be total in relation to the method they employ in their analysis. To trace, measure and explain the interactions between objects, conceptual frameworks, institutions and interests unavoidably one must bring together tools not only from the so-called pure history, the history of science, the history of ideas, and the history of collective psychology, but from almost all the social sciences; anthropology, sociology, economics and psychology. A parallel direction taken years ago by the school of the Annales when it rejected the traditional diplomatic history in favor of a total history.
To design with the aim of ameliorating the human condition of helping to bring about a more equitable society, requires an appropriate program and before that a depth of understanding of the nature of design which historical investigations can promote. Historical research and programmatic analysis, therefore, merge, both being preparatory phases in the design process.
We now come full circle to the point we departed from in order to add to our initial remarks. The recent preoccupation with conservation, preservation and traditional visual vocabularies in professional offices and in schools is not caused merely by feelings of conservatism and fear for the future. It deeply reflects a critical attitude toward accepted "common-sense" needs. definitions of concepts, rules and principles related to design which have been accepted at face value for a long time. History is needed at this time to unearth the roots and reconstruct the mechanisms that have shaped the present design practice.
History must, in the words of Collingwood, be considered as "a science of human affairs...from which men (can) learn to deal with human situations as skillfully as natural science (has) taught them to deal with situations in the world of Nature."
The need for understanding our past may be answered through historical investigations. But it may also be answered through the preservation of concrete objects, provided it is carried out in a salutary way in our traditional communities in order to reveal our origins and explain them in depth, with all their bright spots and shadows, instead of removing them from our sight or turning them into a nostalgic escape.

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