妙法蓮華經玄義 2.210

2.210

為未得者執中生惑，故須無諦。實得者有，戲論者無（云云）。

Because those who have not attained it cling to the middle and produce delusion, it is necessary to speak of truthlessness. For those who have truly attained it, it exists; for those who engage in conceptual proliferation, it does not exist (and so forth).