大方廣佛華嚴經隨疏演義鈔 36.51

36.51

疏「法性本空非觀之使空故無所取」者，此以性空門顯無所取。次云「何有能見者」，即以相待門遣其能見。此中語略，合云：若有所取則有能取，既無所取故無能取，能因於所而得立故。亦曰相因門。然取與見皆通能所，今所取之中則存於所取略無能取，於能見中略無所見，所見即所取故。

Regarding the Commentary's statement, "The dharmatā is fundamentally empty, not made empty by contemplation, hence there is nothing grasped": this uses the approach of nature-emptiness to reveal that there is nothing grasped. Next, it says, "How could there be a perceiver?"—this uses the approach of mutual dependence to dispel the perceiver. The phrasing here is abbreviated; it should properly say: If there were something grasped, there would be a grasper; since there is nothing grasped, there is no grasper, because the agent is established on account of the object. This is also called the approach of mutual causation. However, grasping and perceiving both apply to agent and object; now, within the object grasped, the object grasped is retained while the agent grasping is omitted; within the perceiving agent, the perceived object is omitted, because what is perceived is precisely what is grasped.