大方廣佛華嚴經隨疏演義鈔 75.40

75.40

疏「但心變故非見前法」者，此通喻合。約喻者，即通妨難也。謂有難言：若無實者，何以夢中見色聞聲等耶？故《智論》云「不應言論無實之事。何以故？得緣便生。」夢中之識有種種緣，若無緣，云何生？故今答云：夢中五識不行，所見五塵但心變耳，故《智論》云無也，不應見而見故。如夢中見人頭有角，見身飛等，人實無角、身實不飛故。二約法者，但心變故，合而有義；不見前境，合非有義。

Regarding the Commentary's statement, "It is merely a transformation of the mind, and therefore not the seeing of an external phenomenon": this applies generally to the simile and its doctrinal application. In terms of the simile, it resolves an objection. An objection states: if there is no reality, why does one see forms and hear sounds in a dream? Thus the Mahāprajñāpāramitopadeśa says, "One should not discuss things that have no reality. Why? When conditions are obtained, they arise." The consciousness in a dream has various conditions; without conditions, how could it arise? Therefore, he now replies: in a dream, the five consciousnesses do not operate; the five sense-objects perceived are merely transformations of the mind, and thus the Mahāprajñāpāramitopadeśa says they are non-existent, because one sees what ought not to be seen. It is like seeing horns on a human head or seeing one's body flying in a dream; a human truly has no horns, and the body truly does not fly. Second, in terms of the doctrine: being merely a transformation of the mind matches the sense of existing; not seeing an external object matches the sense of non-existing.