金剛經纂要刊定記 6.158

6.158

"Jñeya" is Sanskrit and has two meanings: first, it means the "mother of cognition", as already explained before; second, it means the "cognitive sphere"—here, however, it is the sphere within samādhi, and this latter meaning is adopted now. The meaning is: the Buddha's cognition knows in accord with the sphere; tathatā has activity and knowing, while sentient beings lack activity and knowing. If it were explained as the mother of cognition, it would be the fundamental cognition realizing the principle of equality without vikalpa, and now contemplating sentient beings is also like this.