In the early modern Korea, some Buddhist intellectuals actively adopted concepts and theories of Western philosophy, and established the modern sense of Buddhist philosophy. They considered Buddhist philosophy as a form of metaphysics. As they thought that Buddhism is basically a philosophical religion that explained human beings and the world using suchness (tathata) or mind as the substance. Hence, they deployed the schema of metaphysics such as ＂phenomenon and reality＂ to understand Buddhist philosophy. They understood Western philosophy to have developed from materialism to idealism, and within the sphere of idealism, from objective idealism to absolute idealism. Such developmental schema of Western philosophy was applied directly to Korean Buddhism to comprehend it in terms of the history of development of idealism. As a result, they made diverse attempts to make a new doctrinal classification of various Buddhist doctrines, through which they treated the Buddhist doctrines that best corresponded to the ideas of the absolute idealism as the most advanced. Furthermore, they extracted the idea of ＂phenomena as reality＂ as the characteristics of Buddhist philosophy, and emphasized that reality does not exist behind the phenomenon, but is expressed directly through the phenomenon.
