成唯識論掌中樞要 2.79

2.79

Regarding 'fearing this might be conflated with that, for the seventh it only establishes the name of manas, etc.': Why is it that the sixth is not merely named manas, while the seventh is also a consciousness? The seventh is a karmadhāraya compound; the two meanings manifest the essence of the consciousness. The sixth is a tatpuruṣa compound; it takes the other to clarify itself. If the sixth were designated solely as 'manas' without saying 'consciousness', it could not manifest itself; if 'consciousness' were added to the seventh, it was feared that it would be conflated with the tatpuruṣa compound. Therefore, the seventh is designated solely with the name manas, fearing this might be conflated with that. The sixth has 'consciousness' added to show that it relies on the other, whereby it obtains its name.