عنوان مقاله [English]
Geographical sciences moreover dominant paradigms epistemology and methodologies in different periods have been affected from geographical scales. The geographical scales have been the guideline of geographers for knowing spatial phenomena and generally universe. This article has done by analytic method and historical approach. It followed the evolution of geographical studies on the base scale and explained the appearance of a new geographical paradigm in form world cities. The research results showed that there are three approaches for studies of spatial phenomena on the foundation of the geographical scales: Mosaic, Systematic and Network. Approximately, every approach dominated on geographical sciences in specific periods. The mosaic approach has been older and dominate paradigm in geography. In fact, it is central-country approach. The systematic approach was seen in the second half of the twentieth century. It used for analyzing core-periphery structure. In the beginning years of the third millennium, the network approach created gradually. The network approach created from the effect of development of information communication technology on space and forming concept of space of flows and space of places. More recently geographers have focused on the concept of networks to explain links between the ‘global’ and the ‘local’ and in doing so have reflected critically on the nature of the former. This focuses on the connections between different people and institutions located on specific nodes across the world. These specific places are the world cities or global cities. This is new phenomena. It emphasizes on the world cities structure. To seem that modern geography needs to all theirs and any theirs can not only explain world facts.