大乘百法明門論開宗義決 1.84

1.84

異義通因熟唯在果者。因謂識中善惡種子。果謂第八種子現行。此善惡因望無記果。因果各別皆得名異。不偏在果故言通因。及成熟時唯在第八種及現行言唯在果。

Regarding "the meaning of 'different' applies to the cause, while 'maturation' pertains solely to the effect": "Cause" refers to the wholesome and unwholesome seeds in the consciousness. "Effect" refers to the seeds and active functioning of the eighth [consciousness]. These wholesome and unwholesome causes, relative to the indeterminate effect, are each distinct and can both be called "different"; because [difference] is not restricted to the effect, it is said to "apply to the cause." And when ripening, it is solely within the seeds and active functioning of the eighth [consciousness]; hence it is said to "pertain solely to the effect."