Long before 1979, Chinese historical research had been dominated by the theory of the Five Modes of Production , according to which the whole Chinese history as well as the other parts of the world had been developed from the first MOD to the last one by one. The modernization theories prevailed during the 1950s and the 1960s, bringing about another uni-linear model of historical changes. For example, W. W. Rostow designed a five-stage process as a universal frame work of economic development, based on which each society could find its position in this uni-line. The task of the less developed societies is just to introduce modernity from the modernized societies so that they can make some developments. Thus modernization is a uni-direction movement as well as a uni-linear process. After 1979, modernization as a new paradigm has been accepted by an increasing number of Chinese historians. The increasing depth and breadth of the academic researches have encouraged such an acceptance, but, admittedly, as a new conceptual system that corresponded to the historic breakthrough and the new direction towards modernization in China. This acceptance also showed the crisis of paradigm , that is, the contradiction between the new themes and the old ones that had dominated Chinese humanities and social sciences. The modernization paradigm based on monistic multi-linear theory considers modernization as a unique breakthrough in history, a great transformation around the whole world, and a historical process that does not have a given ultimate aim and value but different models and routes. The monistic multi-linear theory on historical development is open and all-embracing in historical studies. A variety of historical paradigms is favorable to prosperity of Chinese history.

Use, truth and time constitute the basic elements of the epistemological structure of history. That structure went through three stages: pre-modern (from ancient times to the late eighteenth century, before the professionalization of history took place), modern (the period of professional history, from the late eighteenth century to the 1970s), and post modern (post 1970s). In these three stages, use, truth, and time successively occupied the core of the epistemological structure of history. Postmodernist history, which puts time at the core of its epistemology, is an extreme form of historicism. Even more than historicism, it has emphasized the determining effect of time and change on historical truth and historical consciousness. The privatization of historical narrative and reading has prodded history to become experimental. Experimental history no longer proclaims the truth about the past. Instead, under specific historical circumstances, it strives to produce texts that will be recognized by individual historians and provides these texts to readers, who will make their own judgments. Whether these texts are true will be decided through the uses they produce. In this way, any historiographical practice will be an experiment conducted by an historian in the present and that will consist in searching for the truth about the past. The success of this experiment will depend entirely on the experimental environment, that is, on the conditions provided by the reading environment.

Although a split and turbulent age, the Wei, Jin, and Northern and Southern dynasties, known as the Six dynasties, witnessed a continuous expansion of waterway communication and transportation between north and south China. A significant waterway from Hangzhou to Tianjin held the greatest potential for development during this period, eventually leading to the construction of the Grand Canal in the Sui dynasty.

As the capital of the Sui and Tang dynasties, Chang an brought together large numbers of high-ranking officials, aristocrats, local residents, and sojourners. The promise of profits caused by the high demand for consumer goods attracted merchants. Chang an was also the starting point of the renowned Silk Road. For all these reasons, Chang an became a gathering point for Small and medium-scale merchants, rich merchants, ethnic-minority merchants, and foreign merchants. All these merchants engaged in a wide variety of business activities and made money by surprisingly diverse means. Those with great economic power were quite active politically. The activities of these merchants symbolize the unprecedented growth of commerce in Chang an and reveal the high level of development of urban trade in the Sui and the Tang dynasties.

Northwest China, including the provinces of Shaanxi, Gansu, Ningxia, and a small part of the Inner Mongolian Autonomous Region, was not only one of the earliest developed areas in history, but also one of the most ecologically fragile belts. The traditionally sustainable land reclamation and cultivation policies for the development of an agricultural economy adopted and implemented in administrations during different periods of the Qing dynasty, greatly raised farming and stock production. However, this led to imbalances in the originally fragile ecological environment. The negative effects such as rapidly expanding desertification, worsening water and soil erosions, increased cost of production, enlarged investment, vicious cycles and failing economy can serve as a lesson for contemporary development.

As traditional business organizations that played an important role in China s economy, guilds have faced unprecedented challenges in modern times due to the invasion of Western capitalism and the changes of the traditional Chinese economic structure. It was difficult to maintain the old guild rules, such as limitations on opening new workshops, recruiting new apprentices, etc. Thus, some guilds that insisted on maintaining the old rules fell into decline, while other guilds, either willingly or unwillingly, made reforms in their organization and structural function to adjust themselves to the new situations. The latter gradually transformed into the modern trade association. The different fates of traditional guilds proved that guilds had to reform properly and adapt themselves to new economic and social environments in order to survive in modern times.

Although the opening of Tianjin was forced, it actually accelerated the connection of Tianjin and its hinterland with the international market. The opening brought great changes to the structure of agriculture, animal husbandry, and industry and commerce in the hinterland; encouraged the development of market orientation and international orientation in the hinterland s economy; and greatly improved the occupational organization and income of most farmers and herdsmen. The opening resulted in great progress for the whole modern economy of the hinterland and thereby provided an exemplary case for the study of problems related to the economic modernization process of China.