The Mahayana texts compiled during a few centuries after the Buddha testify to the view here presented. Of these, the one expressly composed to propagate the teaching of the Zen school is the _Laṅkāvatāra_, in which the content of Enlightenment is, as far as words admit, presented from a psychological, philosophical, and a practical point of view. When this was introduced into China and thoroughly assimilated according to the Chinese methods of thinking and feeling, the main thesis of the Sutra came to be demonstrated in such a way as is now considered characteristically Zen. The truth has many avenues of approach through which it makes itself known to the human mind. But the choice it makes depends on certain limitations under which it works. The superabundance of Indian imagination issued in supernaturalism and wonderful symbolism, and the Chinese sense of practicalness and its love for the solid everyday facts of life resulted in Zen Buddhism. We may now be able to understand, though only tentatively by most readers at present, the following definitions of Zen offered by its masters: When Jōshu was asked what Zen was, he answered, “It is cloudy to-day and I won’t answer.”[2.10] To the same question, Ummon’s reply was: “That’s it.” On another occasion the master was not at all affirmative, for he said, “Not a word to be predicated.”[2.11] These being some of the definitions given to Zen by the masters, in what relationship did they conceive of Zen as standing to the doctrine of Enlightenment taught in the Sutras? Did they conceive it after the manner of the _Laṅkāvatāra_ or after that of the _Prajñā-pāramitā_? No, Zen had to have its own way, the Chinese mind refused blindly to follow the Indian models. If this is still to be contested, read the following: A monk asked Kan (Chien), who lived in Haryo (Pa-ling), “Is there any difference between the teaching of the Patriarch and that of the Sutras, or not?” Said the master, “When the cold weather comes, the fowl flies up in the trees while the wild duck goes down into water.” Hō-yen (Fa-yen) of Gosozan (Wu-tsu-shan) commented on this, saying, “The great teacher of Pa-ling has expressed only a half of the truth. I would not have it so. Mine is: When water is scooped in hands, the moon is reflected in them; when the flowers are handled, the scent soaks into the robe.”[2.12] ENLIGHTENMENT AND IGNORANCE ENLIGHTENMENT AND IGNORANCE I