成唯識論演祕 2.426

2.426

若依此論，唯依種子以為命根，命即是根，持業釋也。若《顯揚論》謂業所引異熟六處住時決定，名為命根。現行第八在第六處取彼為命，即命之根，根是種故；或命即根，俱是現故。

According to this treatise, the life-faculty is posited solely based on seeds; the life itself is the faculty, which is a karmadhāraya compound. According to the Prakaraṇāryavācā, the determined duration of the six sensory bases of karmic maturation projected by karma is called the life-faculty. The active eighth consciousness, situated within the sixth sensory base, takes it as life; that is, the root of life, because the root is the seed; or life itself is the faculty, because both are active.