The doctrine of the Two Entrances is evidently taken from the Vajrasamādhi-sūtra[f84]; and that of the Four Acts is an amplification of the second form of Entrance as is expounded in the Sutra. A comparison with the passage[4.29a] from it will make this point clear at once:
“Said the Buddha: The two entrances are ‘Entrance by Reason’ and ‘Entrance by Conduct.’ ‘Entrance by Reason’ means to have a deep faith in that all sentient beings are identical in essence with the true nature which is neither unity nor multiplicity; only it is beclouded by external objects. The nature in itself neither departs nor comes. When a man in singleness of thought abides in chüeh-kuan 覺觀, he will clearly see into the Buddha-nature, of which we cannot say whether it exists or exists not, and in which there is neither selfhood nor otherness. He will also find that the nature is the same both in the masses and in the worthies. He thus firmly holds the ground of the diamond-heart and never moves away therefrom; he is serene and not-doing, and free from conceptual discrimination. This is called ‘Entrance by Reason.’
“‘Entrance by Conduct’ means not to be unsteady and reclining in mind and not to be in its shadows changing like a stream. Wherever you are, let your thought be serene and not to be seeking after anything. Let it be like unto the great earth unmoved even in a raging storm. Giving up all thoughts of egoism in your heart, save all beings and let them cross over to the other shore. There are no births, no signs, no clinging, no abandoning; in the mind of a Bodhisattva, there is no going-out, no coming-in. When this mind which neither goes out nor comes in enters into that which is never entered into, it is called entering. This is the way the Bodhisattva enters into the Dharma. The Dharma is not empty in form, and the Dharma of non-emptiness is not to be put aside as non-entity. Why? The Dharma that is not non-entity is filled with virtues. It is neither mind nor shadows, it is pure in its suchness.”
In comparing these two texts the reader will be impressed with the most important and most striking change Bodhi-Dharma made in his quotation, which is the substituting of pi-kuan for chüeh-kuan. Pi ordinarily means “wall” or “precipice,” and is often found in combination with li, “standing,” in such phrases as pi li wan jên 壁立萬仞, to describe an unscalable wall, or figuratively to represent the attitude, for instance, of Acala-Vidyārāja standing straight up. What was the reason of Dharma’s changing chüeh, “to awaken,” or “to be enlightened” into a word which apparently has no organic relation to the following kuan, “to perceive,” or “to contemplate”? The novel combination is a very important one, for it alters the sense of the whole context in which it occurs. Tao-hsüan, the author of the Biographies, refers to Dharma’s tai ch‘êng pi kuan, Mahayanistic wall-contemplation, in his commentary notes to Zen, as the most meritorious work Dharma achieved in China.[f85] For this reason he is often spoken of as the pi-kuan Brahman, that is, wall-contemplating Brahman, and in Japan the monks belonging to the Soto school of Zen are supposed to follow the example of the founder of their religion when they keep up the practice of sitting facing the wall while meditating. But this is evidently a superficial interpretation of the phrase pi-kuan; for how could mere wall-gazing start a revolutionary movement in the Buddhist world as is implied in Tao-hsüan’s life of Dharma?[f86] How could such an innocent practise provoke a terrible opposition among scholars of those days? To my view, pi-kuan has a far deeper meaning, and must be understood in the light of the following passage in the Records, which is quoted from a work known as the Pieh Chi[4.30] meaning some special document of prior existence:
“The master first stayed in the Shōrinji (Shao-lin-szŭ) monastery for nine years, and when he taught the second patriarch, it was only in the following way: ‘Externally keep yourself away from all relationships, and, internally, have no pantings (or hankerings, 喘 ch‘uan) in your heart;[f87] when your mind is like unto a straight-standing wall you may enter into the Path.’ Hui-k‘ê tried variously to explain [or to discourse on] the reason of mind, but failed to realise the truth itself. The master simply said, ‘No! No!’ and never proposed to explain to his disciple what was the mind-essence in its thought-less state, [that is, in its pure being]. [Later] said Hui-k‘ê, ‘I know now how to keep myself away from all relationships.’ ‘You make it a total annihilation, do you not?’ queried the master. ‘No, master,’ replied Hui-k‘ê, ‘I do not make it a total annihilation.’ ‘How do you testify your statement?’ ‘For I know it always in a most intelligible manner, but to express it in words—that is impossible.’ Thereupon, said the master, ‘That is the mind-essence itself transmitted by all the Buddhas. Harbour no doubts about it.’”
In fact, this passage sums up the special message contained in Dharma’s teaching, and in it we may get an adequate answer as to the exact meaning of pi-kuan. The term must have been a novel one in his day, and the originality of his views really lay in the creative sense of the one word “pi” It was so concrete, so graphic, and there was nothing abstract and conceptual about it. Hence Tao-hsüan’s special reference to Dharma’s teaching as the Tai-chêng pi-kuan. (Mahayanistic wall-contemplation). While there was nothing specifically Zen in his doctrine of “Two Entrances and Four Acts,” the teaching of Pi-kuan, wall-contemplation, was what made Bodhi-Dharma the first patriarch of Zen Buddhism in China.
The author of the Rightful Transmission of the Śākya Doctrine interprets pi-kwan as meaning the state of mind where “no external dusts get in.”[4.31] This may be all right, but we are not told where he finds the authority for this way of understanding. Had he in mind Dharma’s remark to Hui-k‘ê as recorded in the document known as Pieh-chi? In any event the underlying meaning of the “wall-contemplation” must be found in the subjective condition of a Zen master, which is highly concentrated and rigidly exclusive of all ideas and sensuous images. To understand the phrase, “pi-kwan” as simply meaning “wall-gazing” will be sheer absurdity. If the specific message of Dharma as the founder of Zen in China is to be sought anywhere in the writings of his, which are still in existence, it must be in this “Mahayanistic wall-contemplation.”
Besides this writing which is the only one left by Dharma in our possession at present, we have the Laṅkāvatāra-sūtra, Vajrasamādhi-sūtra, and Vajracchedikā-sūtra, through which we can also have a glimpse into the central teaching of Bodhi-Dharma. Zen, unlike other schools of Buddhism, has no particular Sutras to be called the “foundation canon” on which its followers would base the principal tenets of their school; but Dharma recommended the Laṅkāvatāra to his first disciple Hui-k‘ê (Yeka), as containing the teaching most intimately related to Zen, and after him this scriptural writing came to be studied chiefly by Zen scholars.[f88] As to the importance of the Vajrasamādhi as expounding the philosophy of Zen, we can easily understand it from Dharma’s own reference to the Sutra in his writing as was already pointed out. With regard to the Vajracchedikā-sūtra, most people think of it as having nothing to do with Zen prior to the fifth patriarch, Hung-jên (Gunin); for it was he who for the first time introduced it among his own disciples, while Dharma himself made no allusion whatever to this, one of the most popular Buddhist texts in China. But according to Hui-nêng’s Preface to the Vajracchedikā, which is still preserved, “ever since the coming-west of Dharma he wanted to propagate the meaning of this Sutra and lead people to understand the Reason and to see into the Nature.” If this were actually the case, Dharma, to say the least, must have had some knowledge of this Sutra from the very beginning of his career in China, and the connection in a way between this and Zen must have been more fundamental than that between the Laṅkāvatāra and Zen. The prevalent notion then that the Vajracchedikā came only in vogue after Hung-jên and Hui-nêng must be revised. Whatever this may be, the Laṅkāvatāra is too difficult a material for popular consumption, and it was natural that this Sutra came to be gradually superseded by the Vajracchedikā as Zen gained more and more in power and influence. As one of the Sutras belonging to the Prajñāpāramitā class of Buddhist literature, the teaching of the Vajracchedikā was comparatively simple and had something much akin to the Laotzŭan ideas of emptiness and non-doing. It was not hard for the average Chinese to follow its philosophy of Śūnyatā, in fact this agreed well with a certain aspect of Chinese thought.[f89]
However, with Zen followers all literature was like a finger pointing at the moon, and there was not much in itself that will actually lead one to the seeing of one’s own inner nature; for this seeing was a realisation which must be attained by one’s own personal efforts apart from the mere understanding of letters. All Buddhist Sutras including the Laṅkāvatāra, Vajrasamādhi, and Vajracchedikā could not be of much help to the real earnest seekers of the truth, so long as his idea is to grasp the naked facts with his own ungloved hands. This was possible only when his own inner consciousness opened by itself, from within, through his whole-souled efforts. Literature is helpful only when it indicates the way, it is not the thing itself.