因明入正理論疏 2.178

2.178

述曰：第六，相違決定有三，此初標名。具三相因，各自決定，成相違之宗，名相違決定。相違之決定，決定令相違，第三、第六兩囀，俱是依主釋也。有比量云：「此之二因非是過因，三相具故，如二、八因。或二、八因應非正因，具三相故，如此二因。」應為彼立相違量云：「此之二因不定因攝，令敵、證者生疑智故，如五不定。或此二因非正因攝，不令敵、證生定智故，如餘過因。」若二、八因許非正因，便無正量、違教、世間種種過失，故知彼是正因所攝，此二乃是不定所收。二、八句因正因所攝，生敵、證者決定智故，如餘正因。

Commentary: Sixth, the mutually contradictory decisive [reasons] have three parts; this first sets forth the name. Reasons possessing the three characteristics each independently decide and establish contradictory theses; this is called "mutually contradictory decisive" (viruddhāvyabhicārin). The decisiveness of the contradiction, or being decisive so as to make them contradictory—in both the third and sixth case-inflections, it is a tatpuruṣa compound. There is an inference stating: "These two reasons are not fallacious reasons, because they possess the three characteristics, like the second and eighth reasons. Or: the second and eighth reasons should not be correct reasons, because they possess the three characteristics, like these two reasons." One should establish against them a counter-inference: "These two reasons are subsumed under inconclusive reasons, because they give rise to doubtful cognition in the opponent and the arbiter, like the five inconclusive reasons. Or: these two reasons are not subsumed under correct reasons, because they do not give rise to definite cognition in the opponent and the arbiter, like the other fallacious reasons." If the second and eighth reasons were accepted as not being correct reasons, there would be no valid cognition, contradicting scripture and everyday experience with various fallacies; hence we know that they are subsumed under correct reasons, while these two are gathered under the inconclusive. The reasons of the second and eighth propositions are subsumed under correct reasons, because they produce definite cognition in the opponent and the arbiter, like other correct reasons.