The purpose of this research is to have an overall understanding of the traditional city structure, the logic of society=space, within the history of the world. The first step is to recognize and understand spatially for the development process of the ideal traditional city in Japan, France, and China. By zooming and clarifying urban history and theory within these countries, it will bring the realization of the methods that create the modern city.

Thus, as the subject of architectural history and human history as a core, this research is based on the interdisciplinary collaboration between urban history and architectural practice within the past decades. Within this joint research, original methodologies are being explored and established: understanding the urban history as the continuous development, “traditional – modern – contemporary”, using the idea of trichotomy. Understanding the urban history using the précis logic of space theory distinguished from the previous simple comparisons. Understanding and analyzing the urban structure from segmental theory of structure which based on the realization of the structural logic of society=space. Within this joint collaboration, the theme of this research, the city’s idea, and its importance has come to overt.

Architecture and its structure in certain urban area whether consciously or not will be based upon specific idea. Within the construction of the city over time, the juxtaposition and accumulation of the urban idea must be recognized. In other words, understanding and reading of the urban structure from idea will open up the questions and contribute to develop a new methodology. Thus, it is important to clarify the transformation of the shifting period, from modern to contemporary since it would become the powerful tool to find and investigate the problems that the current city has.

All in all, this research project is built upon minute discussion with the research group of urban history from Japan, France and China by the critical analysis and recognition of the situation. The expected consequence of the research will be the establishment of new theory for urban idea, concrete presentation of special comparison between traditional urban cities, Japan, France, and China, the recognition of a point to see and solve the current urban problems. Last but not least, the significance of this research is the possible development which not only it constructs the new methodology for development of research in urban history and theory, but also to establish a strong foundation for the urban design in future.