成唯識論掌中樞要 2.219

2.219

三受俱中識等六支既是種子，云何相應？釋有二義：一、依當生位說；二、依隨順俱有義，亦無違也。故種名俱，俱是相應之異名故。若爾，依有支無當生，云何相應？識等五種當有現行、種說相應，有支威力曾於行支等中，有相應故，種亦說相應。或從識等，當生位說。

Regarding association with the three feelings, since the six links such as consciousness are seeds, how can they be associated? There are two explanations: first, it is explained in terms of their prospective arising stage; second, according to the sense of compliant simultaneous coexistence, there is also no contradiction. Therefore, seeds are called "coexistent", since "coexistent" is another name for "associated". If so, then since the link of existence has no prospective arising, how can it be associated? The five seeds, such as consciousness, will have active manifestations, so seeds are spoken of as associated; since the power of the link of existence was previously associated within the link of formations and so on, seeds are also spoken of as associated. Alternatively, it is spoken from the perspective of the prospective arising stage of consciousness and the rest.