大方廣佛華嚴經疏 6.9

6.9

四現見一切法等者，觀義解脫也。現見之言，揀比知故。真實相言，略有三義：一以智觀事實，事不虛故。故下經文「觀有為法如實相」故。二以慧觀理實，所謂無相，無相不相名為實相。三以無礙智知無二實，窮實故深、盡邊故廣稱智慧海，不為相縛是解脫門。

Fourth, "clearly perceiving all dharmas, etc.," is the liberation of the meaning of contemplation. The words "clearly perceiving" are used to differentiate it from inferential knowledge. The words "true marks" briefly have three meanings: first, using wisdom to contemplate the actuality of phenomena, because phenomena are not false—hence the later sūtra text says, "contemplating conditioned dharmas as having the true mark"; second, using prajñā to contemplate the reality of noumenon, namely the signless, where the signlessness of signs is named the true mark; third, using unobstructed wisdom to know non-dual reality; exhausting reality, it is profound, and reaching the limits, it is vast—hence it is called the ocean of wisdom. Not being bound by marks is the liberation gate.