As terseness and directness is the life of Zen, its literature is full of idiomatic and colloquial expressions. The Chinese as you all know, being such partisans to classic formalism, scholars and philosophers did not know how to express themselves but in elegant and highly polished style. And consequently all that is left to us in ancient Chinese literature is this classicism, nothing of popular and colloquial lore had come down to posterity. Whatever we have of the latter from the T‘ang and the Sung dynasty is to be sought in the writings of the Zen masters. It is an irony of fate that those who so despised the use of letters as conveyor of truth and directly appealed to the understanding of an intuitive faculty became the bearers and transmitters of ancient popular idioms and expressions which were thrown away by the classical writers as unworthy and vulgar from the main body of literature. The reason however is plain. The Buddha preached in the vernacular language of the people; so did Christ. The Greek or Sanskrit (or even Pali) texts are all later elaboration when the faith began to grow stale, and scholasticism had the chance to assert itself. Then the living religion turned into an intellectual system and had to be translated into a highly but artificially polished and therefore more or less stilted formalism. This has been what Zen most emphatically opposed from the very beginning, and the consequence was naturally that the language it chose was that which most appealed to the people in general, that is, to their hearts open for a new living light. The Zen masters, whenever they could, avoided the technical nomenclature of Buddhist philosophy, not only did they discuss such subjects as appealed to a plain man, but they made use of his everyday language which was the vehicle appreciated by the masses and at the same time most expressive of the central ideas of Zen. Thus Zen literature became a unique repository of ancient wisdom. In Japan, too, when Hakuin modernised Zen, he utilised profusely slangy phrases, colloquialisms, and even popular songs. This neological tendency of Zen is inevitable, seeing that it is creative and refuses to express itself in the worn-out lifeless language of scholars and stylists. As the result even learned students of Chinese literature these days are unable to understand the Zen writings, and their spiritual meanings as well. Thus has Zen literature come to constitute a unique class of literary work in China, standing all by itself outside the main bulk of classical literature.