摩訶止觀 7.42

7.42

若觀法性心因緣生法，一種一切種，一心一切心。法性空故，一切心一心，一空一切空。法性假故，一心一切心，一假一切假。法性中故，非一非一切，非空非假雙照空假。九法界心亦復如是。是名「心念處」。

If one contemplates the mind in the dharmatā as a dharma arisen from causes and conditions, one kind is all kinds, and one mind is all minds. Because the dharmatā is empty, all minds are one mind, and one emptiness is all emptiness. Because the dharmatā is provisional, one mind is all minds, and one provisionality is all provisionality. Because the dharmatā is middle, it is neither one nor all, neither empty nor provisional while simultaneously illuminating emptiness and the provisional. The minds of the nine dharmadhātus are also like this. This is called the “mindfulness of mind” (cittasmṛtyupasthāna).