大方廣佛華嚴經隨疏演義鈔 68.14

68.14

疏「五觀七轉識」等者，即真識之用。用而常寂，故說為空。故疏云「皆無自體」，即是空義。

Regarding the Commentary's statement, "Fifth, contemplating the seven transforming consciousnesses..." and so forth: these are the functions of the true consciousness. Operating as function while being constantly quiescent, they are therefore said to be empty. Thus the Commentary states "they all lack self-substance," which is precisely the meaning of emptiness.