But in point of fact where the time-element rules supreme, this was not necessarily the case. As long as our relative minds are made to comprehend one thing after another by degrees and in succession and not all at once and simultaneously, it is impossible not to speak of some kind of progress. Even Zen as something possible of demonstration in one way or another must be subjected to the limitations of time. That is to say, there are after all grades of development in its study; and some must be said to have more deeply, more penetratingly realised the truth of Zen. In itself the truth may transcend all form of limitation, but when it is to be realised in the human mind, its psychological laws are to be observed. The “seeing into thy nature” must admit degrees of clearness. Transcendentally, we are all Buddhas just as we are, ignorant and sinful if you like; but when we come down to this practical life, pure idealism has to give way to a more particular and palpable form of activity. This side of Zen is known as its “constructive” aspect, in contradistinction to its “all-sweeping” aspect. And here Zen fully recognises degrees of spiritual development among its followers, as the truth reveals itself gradually in their minds until the “seeing into one’s nature” is perfected. Technically speaking, Zen belongs to the group of Buddhist doctrines known as “discrete” or “discontinuous” or “abrupt” (_tun_ in Chinese) in opposition to “continuous” or “gradual” (_chien_)[f159]; and naturally the opening of the mind, according to Zen, comes upon one as a matter of discrete or sudden happening and not as the result of a gradual, continuous development whose every step can be traced and analysed. The coming of satori is not like the rising of the sun gradually bringing things to light, but it is like the freezing of water which takes place abruptly. There is no middle or twilight condition before the mind is opened to the truth, in which there prevails a sort of neutral zone, or a state of intellectual indifference. As we have already observed in several instances of satori, the transition from ignorance to enlightenment is so abrupt, the common cur, as it were, suddenly turns into a golden-haired lion. Zen is an ultra-discrete wing of Buddhism. But this holds true only when the truth of Zen itself is considered, apart from its relation to the human mind in which it is disclosed. Inasmuch as the truth is true only when it is considered in the light it gives to the mind and cannot be thought of at all independent of the latter, we may speak of its gradual and progressive realisation in us. The psychological laws exist here as elsewhere. Therefore, when Bodhi-Dharma was ready to leave China, he said that Dōfuku got the skin, the nun Sōji got the flesh, and Dōiku the bone, while Yeka had the marrow (or essence) of Zen.[f160][8.1] Nangaku who succeeded the sixth patriarch had six accomplished disciples, but their attainments differed in depth. He