成唯識論述記 7.94

7.94

述曰：初定有意樂，而不離喜，即一喜受，義說為樂。如《對法》七及五十七、《顯揚》二等說，以此義故總說喜名，即攝彼樂，欲界尋、伺，下地喜、樂，在識各別，體性相離，何不別說？前師問言：汝純受苦處，彼與意苦俱，何緣亦不說，豈以不說即非苦俱？

The Commentary states: The first dhyāna has mental pleasure, yet it is not separate from joy; it is just a single sensation of joy that is conceptually spoken of as pleasure. As explained in the seventh fascicle of the Samuccaya, fascicle 57 [of Yogācārabhūmi], Prakaraṇāryavācā fascicle 2, and elsewhere, by virtue of this meaning it is collectively called by the name of joy, which thereby subsumes that pleasure. In the investigation and examination of the desire realm, the joy and pleasure of the lower stages exist separately in consciousness and are distinct in substance; why are they not stated separately? The former master asks: In your places of unadulterated suffering, where it accompanies mental pain, for what reason is that also not mentioned? Could it be that because it is not mentioned, it does not accompany pain?