摩訶止觀 6.64

6.64

若言假、實諸法體如幻化，乃至涅槃亦如幻化。幻化是易解之空，涅槃是難解之空；舉易況難，而難易皆空。亦如幻人與空共鬪，能觀所觀性皆寂滅。如此空慧體諸見思即幻而真，能成惑智、因果無生，是名空門破假之意。

If one says that the substance of provisional and real dharmas is like an illusion, up to nirvāṇa also being like an illusion: illusion is an emptiness easy to understand, while nirvāṇa is an emptiness difficult to understand; by citing the easy the difficult is illustrated, yet both difficult and easy are empty. It is also like an illusory person fighting with emptiness: the natures of the contemplating and the contemplated are both quiescent. Such wisdom of emptiness, substantiating that all views and thoughts are identical to illusion and thus real, can bring about the non-arising of delusion, wisdom, cause, and effect; this is the purpose of breaking down the provisional through the gate of emptiness.