成唯識論述記 9.205

9.205

述曰：《顯揚》云：心染眾生染，心淨眾生淨。見識真如便能知此染淨心等，約詮即依他，據理即真如。七十七名了別真如。識了別也。

The Commentary states: The Prakaraṇāryavācā says: When citta is defiled, sentient beings are defiled; when citta is pure, sentient beings are pure. Seeing the tathatā of consciousness, one can know this defiled and pure citta and so forth. In terms of designation, it is paratantra; based on principle, it is tathatā. Fascicle 77 names it the tathatā of discernment. Consciousness is discernment.