注大乘入楞伽經 2.206

2.206

This explains the reason why it can be known and why it is difficult to know. Discerning the characteristics of the various bhūmis and having good mastery of the meanings of phrases through the power of wisdom constitutes the revelatory cause (jñāpaka-hetu). Having extensively accumulated roots of goodness in the presence of boundless Buddhas constitutes the contributory cause (sahakāri-hetu). The originally existent primary cause (kāraṇa-hetu) is thereby brought to the fore, and one naturally sees clearly the stream of false habits; hence it is said that they "are able to know it."