In principle, Sangha includes all members from different Buddhist communities in different places. In reality, however, it is impossible to gather all monks and nuns from all over the world together. Therefore, Sangha in different regions were allowed to set up a bounded area(sīmā) for performing their own duties and training. This kind of practice is called sīmā-bandha. Vinaya-piṭaka, nevertheless, does not have a specific section on this topic and thus sīmā-bandha is not discussed systematically. Studying the Vinaya canon in detail, the Chinese Buddhist masters distinguished sīmā into two categories: “natural” and “artificial”, and there are seven types of sīmā which have different standards and regulations. As for the contemporary Buddhist studies, less attention has been drawn to this topic,especially the “natural boundary”. This article will make use of Chinese Vinaya canon and the explanations and annotations by Chinese Buddhist masters, to discuss different types of sīmā and their relationships, with an eye to contribute new knowledge in the study of Vinaya.
