大般涅槃經義記 8.174

8.174

此後一義與〈聖行〉中辯性相似，今此所論義當後門。云何得知？此中辯釋非因果性，即是真諦常、樂、我、淨不變之法，故上說言因緣中道常、樂、我、淨。前問所辯乃是世諦無常、苦、空、無我之法，三乘同知，故非此義。

This latter meaning resembles the explanation of nature in the "Chapter on Holy Practice"; what is discussed here corresponds in meaning to the latter gate. How is this known? The neither-cause-nor-effect nature explained here is precisely the unchanging dharma of permanence, bliss, self, and purity of the ultimate truth; hence it was stated above that the middle way of dependent origination is permanent, blissful, self, and pure. What was distinguished in the previous inquiry was the dharma of impermanence, suffering, emptiness, and non-self of conventional truth, known in common by the three vehicles, and therefore is not this meaning.