大乘起信論裂網疏 2.12

2.12

The mind's tathatā is the essence of the dharma-gate of the great general characteristic of the one dharmadhātu. This is because the fundamental nature of the mind is the mark of neither arising nor ceasing. All dharmas possess distinctions solely due to deluded thoughts; if one is free from deluded thoughts, then there are no marks of distinction among objective realms. Therefore, all dharmas from the beginning have in their nature been free from speech, cannot be overtly expressed by any written words, and, apart from the mind's cognitive grasping, have no marks whatsoever; they are ultimately equal, eternally without alteration, indestructible, and solely the one mind, and for that reason are called tathatā.