成唯識論述記 8.350

8.350

述曰：謂無明行者，出能引體，能引識等五果種故。釋能引名，雖此二支與生、老死為引因體，而前十支俱是因故，不可遠望二果為能引支故，但望近所增之種，名能引也。

The Commentary states: 'Ignorance and saṃskāra' presents the essence of the projector, because they project the seeds of the five results such as consciousness. Explaining the name of 'projector': although these two links serve as the essence of the projecting cause for birth and aging-and-death, because the preceding ten links are all causes, they cannot be called projecting links by looking distantly toward the two results; they are called 'projectors' solely by looking to the seeds proximately increased.