[...] I decided to concentrate on the main stream of the Buddhist tradition. The bulk of the selections are derived from the Old Wisdom School, and in particular from Buddhaghosa's Path of Purity, a work of unquestioned authority. No justice could be done to later development, which often gratly depart form the original impulse. Of the very important Tantra only one extract could be included (III 3). The bhaktic Amida schools, with their visions of Buddhas and their Paradises, are represented by no more than a brief Note (I 4). And the Ch'an school has not be mentioned at all, although it developed a new and fascinating system of meditation, based on koans, and upheld the Buddhist tradition in a typically Buddhist way by denying it. (p.27)