Among urban planners, there was an idea that certain types of town plans provided a means of combatting aging and decay. Michel Parent, museum conservator of relief plans, writing in 1948, considered that the knowledge of ancient could be seen as an “applied science of curation”:
The past can serve the future in all cases, on the condition that we do not make a tyrant of it: firstly, it highlights tried-and-tested postulates or permanent laws which are helpful in finding solutions to new problems; secondly, in specific cases, awareness of a pathological evolution of a city or district enables us to distinguish between healthy and sick parts, providing urban planners with genuine remedies.31(Parent 1948, p. 282)
These approaches place a particular emphasis on one time of plan: that of planned cities, considered in this case of works of art.
1.3.2. The ancient plan as a work of art
Toward the end of the 19th century, the Austrian architect Camillo Sitte, in Der Städtebau – published in English as City Planning According to Artistic Principles – emphasized the esthetic qualities of the medieval town, “rediscovered” by the Romantic movement (Sitte 1890). In Germany, Sitte’s contemporaries, the architect Joseph Stübben and the art historian Albert Erich Brinckmann, highlighted the interest of studying ancient city plans in order to identify models of successful urban arrangements (Stübben 1890; Brinckmann 1908). In England, Raymond Unwin demonstrated that ancient urban forms provided a valuable source of models for town development (Unwin 1981). In 1926, Lavedan aimed to lay scientific foundations for this approach in his seminal essay Qu’est-ce que l’urbanisme. The publication was accompanied by a selection of ancient, medieval and modern plans; the way in which certain forms, such as the checkerboard, appeared again and again was seen to be particularly notable (Lavedan 1926a, 1926b, 1941). This approach, labeled “culturalist” by the architectural historian Françoise Choay (1965), emphasized ancient city layouts with a certain esthetic value, giving them the potential to be used as models in developing an art of urban design.
In order to establish his history of urban architecture as a science, Lavedan needed to define a position for it among all of the other disciplines for which the town was an object of interest in the early 20th century (geography, sociology, economics, history, etc.). He chose to focus on one aspect of urban studies which, in his view, had been largely ignored in other disciplines: the notion of the plan from the perspective of material elements (road traces, arrangement and specialization of different districts, design of public squares and parks). However, given the proximity of this approach to geography, Lavedan chose to focus only on urban plans with a certain esthetic value, considered from an artistic perspective, in order to “establish, with respect to related disciplines, the possibility of an independent discipline in the history of urban architecture, written from a purely artistic and esthetic perspective” (Lavedan 1926a, p. 7)32. It was plans of this type that Lavedan selected for publication in later collections (Lavedan 1926b, 1941).
1.3.3. The ancient plan as a societal project
At its heart, 19th and 20th century urbanism carried the idea that the choice of a type of plan or building scheme could promote the development of a societal model. The urban plan was seen to have the potential to establish a spatial order that would also imply a social order. Notions of architectural disorder are often closely linked to ideas of social disorder in discussions of urban design (Poïesis 1998). Up until the 1970s, urban design projects were still being presented as “harbingers of spatial order, opposing urban chaos and fragmentation” (Choay and Merlin 1988, p. 625). For the culturalists, the idea of reviving a former, “ordered” state was closely linked to a desire to normalize “chaotic” industrial cities (the same type of logic is still applied in the context of discussions surrounding suburban development, city outskirts, etc.). The esthetic qualities inherent in certain older configurations had been confirmed over the course of history, an opinion supported by the recurrence of these arrangements, confirming the intrinsic value of the plan. Thus, the mother form was also considered as a social project. According to this perspective, space is seen as a relatively neutral substrate, a canvas for the models applied to them by urban designers – models that could be adapted to any location and time, with no need to account for the specific characteristics of geographical sites or for the unique trajectory of a place. On the contrary, dissociation from the natural milieu was seen as a potential criterion for ensuring the durability of an urban form.
1.3.4. Artificial versus natural forms
From an early date, observations of persistence were linked to the idea that manmade forms had a greater capacity to withstand the test of time than natural forms, simply due to the role played by human rationality in their creation. For N. Bergier, ancient roads survived primarily due to the role of human reason:
The form of the great highways is artificial, consisting of an assembly and arrangement of the aforementioned materials in a certain order, invented by human industry through the use of reason: not only to create them, but also to preserve them as long as the craftsmen’s art and the nature of the materials themselves would permit.33 (Bergier 1622, p. 135)
Bergier’s whole work was devoted to the development of an ideal model of the ancient road, which he presented as a veritable architectural order (Robert and Verdier 2014, pp. 11–71). He created a classification of highway-building materials using a scale of values, from the least useful natural deposits to the most sophisticated man-made materials, such as “Tiles [...] formed not by the hazards of time, but using rule and compass”34 (Bergier 1622, p. 193).
The same type of opposition resurfaced three centuries later in the work of Lavedan, who suggested that towns could be split into two categories: “spontaneous towns, born of chance and which grew up gradually, and artificial towns, created in a single day by the will of one man”35. In the first case, he considered that towns “left to chance, or to nature, the task of grouping the component elements around the generating element” (road, watercourse, relief, etc.), while artificial towns were “constructed following a predetermined plan”. He added that the latter represent “the specific object of study of a history of urban architecture: not always works of beauty, but always works of art, or in other terms, intentional creations of human ingenuity”36 (Lavedan 1926a, p. 5). Lavedan established a hierarchy of plans based on their independence with respect to the natural dispositions of the host site and on their geometric complexity: from the “inorganic village, in which dwellings seem to have sprung up at random” to “the checkerboard plan, with a grid pattern which is now the boast of many cities of the New World, from Buenos Aires to Chicago”37(Lavedan 1926a, p. 31). The artificial form as a work of art, particularly the regular geometric plan, was seen as a product of human rationality forging a structure with the capacity to slow the decay of forms under the influences of time and nature (section 1.2.5). Thus, while M. Poëte emphasized the role of natural sites and of the location of towns within a network of transport arteries in the context of urban planning, P. Lavedan developed an esthetic vision independent of geographic realities. This approach left an indelible mark on the study of urban morphology, both in architecture