大乘起信論裂網疏 3.72

3.72

不相應無明者，正指第八識中無明種子，不與第八識現行相應也。此明雖由無始已來無明力故，法爾有此八識及諸心所各各四分，乃至一切境界。然此諸法原無改變、原無變易，仍是一真法界。若能念念觀察動心即不生滅，即得入真如門，即為證得如來智慧。特以偶爾失照，不覺一法界故，則第八識中無明種子即與前七相應，而現行分別遂起，復生諸染心也。

'Unassociated ignorance' specifically refers to the seeds of ignorance within the eighth consciousness, which are not associated with the active manifestations of the eighth consciousness. This explains that although through the power of ignorance from beginningless time, by the nature of things there are these eight consciousnesses, the various mental factors each with four aspects, up to all sense-realms, nevertheless these dharmas originally have no alteration and originally have no change; they are still the one true dharmadhātu. If in thought after thought one can contemplate that the moving mind is itself free from arising and ceasing, one then enters the aspect of tathatā and realizes the Tathāgata's wisdom. It is only because of occasionally losing awareness and not being enlightened to the one dharmadhātu that the seeds of ignorance in the eighth consciousness immediately associate with the first seven, active discriminations thereupon arise, and they again produce the various defiled minds.