瑜伽師地論略纂 3.18

3.18

「有性是障緣」等者，有性，謂有體性。果性，謂因所有，即體名為義，名果性。此中問：有體作障緣？為果義作障緣？若有體是障緣，體性常有，是則性永不得顯，顯如未顯，常有體故。因亦常有，何不為障，而獨果有，能為障耶？量云：汝宗之果應永不顯，常有性故，猶如未顯。　汝宗因體亦應為障，體常有故，猶如於果。「若言果性是障緣」者，如芽一法，亦因亦果，望種是果、望莖是因。望莖不障、望因能障，障義攝顯、不顯，故成一法亦顯、不顯。應立量云：汝宗果體亦應不顯，有因體故，如自性因。然彼宗果體一向顯，故為此難。　或汝自性體亦應果顯之因故，如後果因。猶彼執芽是因必顯，故成斯難。　或應果性非障，體即因故，如因。　因亦應障，即果體故，如果。故言一法亦因亦果。

Regarding "The nature of existence is the obstructing condition," and so forth: "nature of existence" refers to having substantial nature. "Nature of effect" refers to what belongs to the cause—that is, the substance designated as an entity is called the nature of effect. Here we ask: Does having substance act as an obstructing condition, or does being an entity that is an effect act as an obstructing condition? If having substance is the obstructing condition, since substantial nature is permanently existent, its nature could never be manifested; being manifested would be like not yet being manifested, because it always has substance. The cause also always exists; why does it not act as an obstruction, while only the existence of the effect can act as an obstruction? The formal inference is: "The effect in your school should never be manifested; because it permanently has nature; just like [when it is] not yet manifested." "The substance of the cause in your school should also act as an obstruction; because its substance is permanently existent; just like the effect." Regarding "If you say that the nature of an effect is the obstructing condition": take a single phenomenon such as a sprout, which is both a cause and an effect; relative to the seed it is an effect, and relative to the stem it is a cause. Relative to the stem it does not obstruct, while relative to the cause it can obstruct; since the meaning of obstruction subsumes both manifestation and non-manifestation, this would mean that a single phenomenon is both manifested and unmanifested. One should formulate the inference: "The substance of the effect in your school should also not be manifested; because it has the substance of a cause; like the cause of the primal nature (prakṛti)." However, in their school the substance of the effect is exclusively manifested, which is why this objection is raised. Or: "The substance of your primal nature should also be the cause of the effect's manifestation; like the cause of a subsequent effect." Since they hold that a sprout is definitely manifested as a cause, this objection is established. Or: "The nature of the effect should not be an obstruction; because its substance is identical to the cause; like the cause." "The cause should also obstruct; because it is identical to the substance of the effect; like the effect." Hence it is said that a single phenomenon is both cause and effect.