仁王護國般若波羅蜜多經疏 2.516

2.516

問：此有無等，為一法前後、為兩法俱時相形待耶？答：有無俱時，待唯一法，如將一丈對丈五等，即彼一丈而有短相，對五尺等即無短相而有長相，故彼一丈短長二相，體俱無故。一法前後，例此應知。如第二月者，結無實體。由眼病故，見第二也。開一觸一，見一謂二；閇一觸一及眼無病，即無二也。由心病故，妄見有無一異好醜及長短等，示令觀察，如月無矣。從此第六明緣成假。

Question: Are this existence and nonexistence, etc., mutually relative as one dharma earlier and later, or as two dharmas simultaneously? Answer: Existence and nonexistence are simultaneous, relative to a single dharma. For example, if one takes ten feet and contrasts it with fifteen feet, that very ten feet has the characteristic of being short; if contrasted with five feet, it does not have the characteristic of being short but has the characteristic of being long. Therefore, regarding that ten feet, both the characteristics of short and long are devoid of substance. One dharma earlier and later should be known by analogy with this. 'Like a second moon' concludes that it has no real substance. Because of an eye disease, one sees a second [moon]. If one opens one eye and presses the other, one sees one and thinks it is two; if one closes one and presses the other, or if the eye has no disease, there are no two [moons]. Because of a disease of the mind, one falsely perceives existence and nonexistence, one and different, beautiful and ugly, long and short, and so on; showing them enables one to contemplate that they are nonexistent, like the [second] moon. Hereafter, the sixth part explains the designation of conditioned assembly.