成唯識論述記 7.715

7.715

述曰：第二師：亦定有疎所緣緣，亦親所緣也。此第八識要杖他變為本質方能自變故，即種子等亦杖他變，望自身雖為本質，望他即為影像，即是變他根之師。

The Commentary states: The second master: it also definitely possesses a remote objective condition as well as an immediate objective condition. This eighth consciousness must rely on what others transform as an archetype before it can transform itself; that is, seeds and so forth are also transformed relying on others. With respect to one's own stream, it serves as an archetype, but with respect to others, it serves as a reflected image; this is the master who holds that it transforms the faculties of others.