二諦義 2.85

2.85

問：若爾，用真俗何為耶？解云：真俗標別二諦，明此是真諦、此是俗諦，由真諦顯彼是俗諦，猶如一赤色，雖同是赤色，而色有勝劣，此是劣赤、此是勝赤，由劣赤顯此是勝赤，勝劣兩赤待。二諦亦爾，俗是劣諦、真是勝諦，勝劣兩諦待。凡聖、空有、真俗皆例爾。

Question: If so, what is the purpose of using ultimate and conventional? Explanation: Ultimate and conventional mark the distinction between the two truths, clarifying that this is ultimate truth and this is conventional truth. Through ultimate truth it is manifested that the other is conventional truth. It is just like the color red: although both are alike in being red, color has superior and inferior—this is inferior red, and this is superior red; through the inferior red it is manifested that this is superior red, and the two reds, superior and inferior, are mutually dependent. The two truths are also like this: the conventional is the inferior truth, and the ultimate is the superior truth; the two truths, superior and inferior, are mutually dependent. Ordinary and noble, empty and existent, ultimate and conventional are all analogous to this.