瑜伽論記 5.262

5.262

法施設建立，謂名身句身文身等者，出聲明體。及五德等者，由彼聲體具五德故方成聲論，勝能詮聲，聲論者說，謂名句文體明則是聲，聲性是常音響是無常，無常之響顯於常聲，若知常聲名聲明。

Regarding "the conceptual designation and establishment of dharmas, that is, the collection of names (nāmakāya), collection of phrases (padakāya), collection of phonemes (vyañjanakāya), and so forth": this reveals the essence of linguistic science. Regarding "and the five virtues, and so forth": because that essence of sound possesses the five virtues, it only then constitutes a treatise on linguistic science. Regarding supreme expressive sound, the linguistic theorists say: the essence of names, phrases, and phonemes is clarity, which is sound; the nature of sound is permanent, whereas audible resonance is impermanent. The impermanent resonance manifests the permanent sound; knowing this permanent sound is called linguistic science.