妙法蓮華經玄義 3.128

3.128

若欲顯智，要須觀成。汎論觀、智俱通因果；別則觀因智果。例如佛性，通於因果；別則因名佛性，果名涅槃。今就別義，以觀為因，成於智果。如《瓔珞》云：「從假入空名二諦觀；從空入假名平等觀；二觀為方便道，得入中道第一義諦觀。」今用從假入空觀為因，得成於果，名一切智；用從空入假觀為因，得成道種智果；用中觀為因，得成一切種智果也。

If one wishes to reveal wisdom, it requires that contemplation be perfected. Speaking generally of contemplation and wisdom, both apply to cause and effect; specifically, contemplation is the cause and wisdom is the effect. For example, buddha-nature applies to cause and effect; specifically, the cause is named buddha-nature, and the effect is named nirvāṇa. Now, following the specific meaning, taking contemplation as the cause perfects the effect of wisdom. As the Yingluo jing says: 'Entering emptiness from the provisional is called the contemplation of the two truths; entering the provisional from emptiness is called the contemplation of equality; these two contemplations serve as the path of expedients to enter the contemplation of the middle way's paramārtha-satya.' Now, using the contemplation of entering emptiness from the provisional as the cause, one achieves the effect, named the wisdom of all [phenomena]; using the contemplation of entering the provisional from emptiness as the cause, one achieves the effect of the wisdom of the paths; using the contemplation of the middle as the cause, one achieves the effect of the wisdom of all modes.