The notion of qi/gi (氣) is one of the most pervasive notions found within the various areas of the East Asian intellectual and cultural traditions. While the pervasiveness of the notion provides us with an opportunity to observe the commonalities amongst the East Asian intellectual and cultural traditions, it also allows us to observe the differences. This book focuses more on understanding the different meanings and logics that the notion of qi/gi has acquired within the East Asian traditions for the purpose of understanding the diversity of these traditions. This volume begins to fulfill this task by inquiring into how the notion was understood by traditional Korean philosophers, in addition to investigating how the notion was understood by traditional Chinese philosophers.