成唯識論述記 3.647

3.647

述曰：何者為假？識緣於此現法之時，尋所從生說之為因，說現為果。尋現世法及所生法，變似未來之相，現名為因，未來為果，故言假也。而實所觀之法，非因非不因，非果非不果。且如於因，性離言故，非定是因；有功能故，非定不因，果亦如是。

The Commentary states: What is meant by "conventionally designated"? When consciousness takes this present dharma as an object, tracing where it arose from, it speaks of that as the cause and speaks of the present as the effect. Tracing present dharmas and what they produce, it transforms resembling the appearance of the future, designating the present as cause and the future as effect; hence it says "conventionally designated". But in reality, the observed dharmas are neither cause nor non-cause, neither effect nor non-effect. Take, for instance, a cause: because its nature is ineffable, it is not determinately a cause; because it possesses capacity, it is not determinately a non-cause. The same applies to an effect.