維摩經玄疏 6.43

6.43

一、中道佛性合真諦為二諦者，猶是通教之二諦也。非祇通二乘，亦通別、通圓也。所言中道合真為第一義諦者，《涅槃經》云「言佛性者，即是第一義空。第一義空，名為智慧。智者見空，及與不空」，不空即是中道，空即是真諦，故知中道佛性合真諦，為第一義諦也。亦有三種二諦，類前可知。

First, the two truths in which the middle way buddha-nature is combined with the ultimate truth are still the two truths of the shared teaching. They are not shared only with the two vehicles, but are also shared with the distinctive and shared with the perfect. As for what is called combining the middle way with the ultimate to constitute paramārtha-satya, the Nirvāṇa Sūtra states: "What is called buddha-nature is precisely the emptiness of the supreme meaning. The emptiness of the supreme meaning is called wisdom. The wise see emptiness and also non-emptiness." Non-emptiness is precisely the middle way, and emptiness is precisely the ultimate truth. Hence we know that the middle way buddha-nature combined with the ultimate truth constitutes paramārtha-satya. There are also three kinds of two truths here, which can be known by analogy with the preceding.