大方廣佛華嚴經隨疏演義鈔 37.5

37.5

疏「若以第一義空為佛性者，唯是正因」者，揀異智慧性也。然《涅槃》云「佛性者名第一義空，第一義空名為智慧，此二不二以為佛性。」然第一義空是佛性性，名為智慧，即佛性相。第一義空不在智慧但名法性，由在智慧故名佛性。若以性從相，則唯眾生得有佛性，有智慧故。牆壁瓦礫無有智慧，故無佛性。若以相從性，第一義空無所不在，則牆壁等皆是第一義空，云何非性？故下經云「知一切法即心自性」，論云「以色性即智性故，色體無形說名智身；以智性即色性故，說名法身。偏一切處，明體本均。」今分性相，故分二義。

Regarding the Commentary's statement, "If one takes the emptiness of the ultimate truth to be Buddha-nature, it is purely the primary cause": this distinguishes it from the nature of wisdom. However, the Nirvāṇa Sūtra states: "Buddha-nature is named the emptiness of the ultimate truth; the emptiness of the ultimate truth is named wisdom. These two are non-dual and constitute Buddha-nature." Now, the emptiness of the ultimate truth is the essence of Buddha-nature, while being named wisdom is the characteristic of Buddha-nature. When the emptiness of the ultimate truth is not within wisdom, it is merely named dharmatā; because it is within wisdom, it is named Buddha-nature. If one subsumes the essence under the characteristic, then only sentient beings have Buddha-nature, because they have wisdom. Walls, tiles, and gravel have no wisdom, so they lack Buddha-nature. If one subsumes the characteristic under the essence, then since the emptiness of the ultimate truth is nowhere absent, walls and the like are all the emptiness of the ultimate truth—how could they not be the nature? Therefore, a later passage of the sūtra states: "Know that all dharmas are the mind's own nature." A treatise says: "Because the nature of form is itself the nature of wisdom, the essence of form, being formless, is termed the wisdom-body; because the nature of wisdom is itself the nature of form, it is termed the dharmakāya. It pervades all places, clarifying that the essence is fundamentally equal." Here, essence and characteristic are differentiated, and so two meanings are distinguished.