成唯識論演祕 6.376

6.376

若離出體其方便中，不攝中間二緣爾者，論何不說中間二緣是能生收？論既不說能生因攝，明是增上，故知方便具攝三緣，增上即是方便攝故。

If, in setting forth the essence separately, the auxiliary (upāya) does not subsume the intermediate two conditions, why would the treatise not state that the intermediate two conditions are included under the productive cause? Since the treatise does not say they are subsumed under the productive cause, it is clear they are sovereign (adhipati); hence we know that the auxiliary fully subsumes the three conditions, because the sovereign is subsumed under the auxiliary.