成唯識論述記 1.146

1.146

述曰：隱劣顯勝故，謂所與心非定俱起，如貪、信等，時不現行，不可說所義兼於心，故說識言，亦攝心所。問：遍行五所，心定相應，何不說彼，而但說識？答：識為主故，能生彼故。彼五種類，非定俱行，故但說識，即攝心所。問：真如與識，非如心所，何故此中亦不說有？答：識實性故，識俱有故，不離識故，非我、法依，故但說識，不說真如。

The Commentary states: Because it conceals the inferior and reveals the superior; that is, the mental factors and the mind do not invariably arise together—for example, greed, faith, and so on are at times not active—one cannot say that the meaning of 'mental factors' subsumes mind. Therefore, speaking of 'consciousness' also includes mental factors. Question: The five omnipresent mental factors are definitely associated with mind; why does it not mention them, but only speaks of consciousness? Answer: Because consciousness is the master, and because it can generate them. Those five categories do not invariably operate together [with all states]; therefore, by merely speaking of consciousness, it includes mental factors. Question: Tathatā and consciousness are not like mental factors; why is it not said to exist here either? Answer: Because it is the real nature of consciousness, because it is concurrent with consciousness, because it is not separate from consciousness, and because it is not the support for self and phenomena, it only speaks of consciousness and does not speak of tathatā.