大般涅槃經義記 5.152

5.152

下廣辯中有二問答：前一問答明諦體一，不相離故；後一問答明諦相異，淺深別故。就前問中，先牒二諦總問云何，次就二諦問相有不。下就設難，「如其有者即是一諦」就有徵難；「如其無者將非虛妄」就無遮責。下佛答之，「世即第一」，以相即故亦得相有。

In the extensive discussion below, there are two questions and answers: the first question and answer explains that the substance of the truths is one because they are not separate from each other; the second question and answer explains that the marks of the truths are distinct because of their difference in shallowness and depth. In the first question, he first reiterates the two truths and asks generally what they are; next, in relation to the two truths, he asks whether marks exist or not. Below, in setting up objections: 'If they exist, then they are one truth' is a query and objection based on existence; 'If they do not exist, might they not be false?' is a refutation and censure based on nonexistence. Below, the Buddha answers it: 'the conventional is identical to the ultimate'; because they are mutually identical, mutual existence is also obtained.