Perceptible worlds，feasible worldsAuthor：Cristina BrumatCity changing is not a recent subject. Since many years, critics and planners have debated about city decline, even in a sort of playback of urban history. A great many and contradictory images and anticipations have characterized the last twenty years. In the Sixties the urbanization process seemed relentless and the term megalopolis, provided by Gottman to de-fine the new urban settlements, had soon acquired an evocative meaning of a nearly pathological phenome-non: a cancer that is spreading throughout the worlds surface. Since the Seventies all the industrialized countries have witnessed the drop of the urban growth. This reversed tendency led many re-searchers to put forward the hypothesis of a crisis, the death of urban growth model. The decrease in the popu-lation growth affected basically the big cities, though this aspect was not given much thought. There was therefore talk of the so-called counter-urbanization phenome-mon which, according to Berry is a tendency that continued throughout the twentieth century. This would lead to the creation of an urban civilization without ci-ties. According to the author, this tendency is to be ascribed to an attitude of individualism, the free circula-tion of people and the fear of violence afflicting the Ame-rican cities urged people to search for safe areas. He actually maintained that expansion and urban degrada-tion are the product of an array of individual decisions in the framework of a tradition of privatism. The dangers and the evils that, in the past, had been at-tributed to a rapid urbanization process began to be ascribed to the decline of big cities, with the result that the analyses and the studies carried out by different schools gradually con-firmed the urban crisis picture.The recognition of the demographic decline affecting big cities coincided with the evolution of the productive or-ganization processes optimizing space and labour Elec-tronic technology with its outstan-ding product and process innovations produced an inten-sification and dematerialization of trade, a compression of time and space; besides an overall mo-dification of personal, social, productive and spatial communications.Todays reality demonstrates that the city is far from dying or declining. The urbanization process of the ground goes beyond the city as well as the everyday crowding of cities and the worsening of environmental issues basically related to air, water and sound pollution. In order to interpret the dynamic key of the metropoli-tan transformation, it is still resorted to the mental categories of the past, while the decision to move to the neighbouring su-burbs is not to be meant as an escape, but as an expres-sly chosen location within the boundaries of the new ur-ban system under development.Therefore we are going through a time when the urban structure and individuals habits, behaviours and values are changing radically. The house turns into the core, meant as the intersection between family and reproduc-tive functions; revival and mobility seem to be part of the processes through which occurs this transition. In the case of revival, there pre-vails the continuity with the past; in view of integration, the symbolism an architectural and urban design past can generate, is estimated to be useful. The mobility, vi-ceversa, views the city in terms of functions and spaces necessary to the present: the important values are those heading for change, innovation and are not concerned with the search for the symbolic spatial and historical sense of the site.People living in cities suffer the pressure and the threat coming from new groups. This derives not only from the recent migration movements, but also from the invasions of city users, commuters and metropolitan consumers who use and abuse the city.The result is a reduced capability of the city to involve the individuals in getting familiar, participating and de-ciding about the citys issues and, as a consequence, its difficulty to emerge as an object making sense. The leading urban life style seems to be that described by Simmerl first and Wirth afterwards: unconcerned, superficial, anony-mous, with deviation and borderline phenomena affec-ting growing numbers of people.The spatial sense proposed does not always correspond to that desired or expected by citizens. The adaptation to the urban environment is basically perceptive. It is preci-sely through the analysis of perceptive phenomena, the images the individuals have of the site that it is possible to identify the needs and the aspirations for the future. The perception of a spatial organization offers planning the possibility to un-derstand these elements and the guarantee that design represents the synthesis of the environmental aspirations of the groups who make up the social structure. There does not exist a unique image of the city, each in-dividual makes a