因明入正理論疏 2.20

2.20

述曰：下解異有四：一牒名、二總顯、三別指、四釋成。此即初二。處謂處所，除宗已外，有無法處。謂若有體，若無體法，但說無前所立之宗，前能立因亦遍非有，即名異品，以法異故、二俱異故。《理門》頌云「宗無因不有」，是名異法。有解：正取因之異品，由無此故宗必隨無，故亦兼取無宗名異，合名異法。復自難言「若但無因，即名異法，同品非有應是異喻」者，若爾，聲無常宗，以電瓶等而為同喻，勤勇之因於電非有，應成異品，宗定隨無。由此應言同成宗故，因為正同，宗為助同。異品離故，宗為正異，因為助異，偏取非異。故《理門》云：「宗無因不有，名為異法，不云因無宗不有，名為異喻。」然此不欲別成異法，故先無宗，後方無因。

The commentary states: Below, the explanation of heterogeneity has four parts: first, restating the term; second, general elucidation; third, specific designation; fourth, explanatory justification. This corresponds to the first two. "Place" refers to a locus: the loci of existent and nonexistent things apart from the proposition. That is, whether an entity exists or does not exist, so long as it is stated that the preceding probandum of the proposition is absent, the preceding probans of the reason must also be universally nonexistent; this is called a heterogeneous instance, because the property is different, and because both are different. The verse in the Nyāyamukha states: "Where the proposition is absent, the reason does not exist"—this is called a heterogeneous property. There is an explanation: It primarily takes the heterogeneous instance of the reason, because when this is absent, the proposition is necessarily absent along with it; therefore, it also secondarily takes the absence of the proposition as heterogeneous, and together they are called a heterogeneous property. It then objects to itself: "If mere absence of the reason is called a heterogeneous property, then absence in the homogeneous instance should be a heterogeneous example." If so, with sound as impermanent as the proposition, taking lightning, pots, and so forth as homogeneous examples, the reason "arising from effort" does not exist in lightning, and so lightning would become a heterogeneous instance, and the proposition would necessarily be absent along with it. From this, one should say that because they homogeneously establish the proposition, the reason is the primary homogeneous [factor], and the proposition is the auxiliary homogeneous [factor]. Because heterogeneous instances are separated [from the proposition], the proposition is the primary heterogeneous [factor], and the reason is the auxiliary heterogeneous [factor]; taking only one does not constitute heterogeneity. Therefore, the Nyāyamukha states: "Where the proposition is absent, the reason does not exist—this is called a heterogeneous property; it does not say that where the reason is absent, the proposition does not exist, calling that a heterogeneous example." However, here one does not wish to establish a distinct heterogeneous property; therefore, first the proposition is absent, and only thereafter is the reason absent.