因明入正理論疏 2.81

2.81

若有依教名為自語，此中亦有全分、一分二種四句。全四句者，有違自語非他，如順世外道對空論言「四大無實」。彼說四大必非無實，彼云無實必非四大，以違自教自語非他。有違他語非自，如佛法者對數論言「彼我非受者」。彼所說我必非非受者，若非受者必非彼我，故違他教他語非自。有俱違自他語，謂如一切言皆是妄，此依違教方有諸句，故此一分句亦即是前一分自教相違，義准應悉。二四句中，違自及共，皆此過攝。其違共中，違他非過，違自為失，故此但名自語相違。雖俱不違，非此過攝，兩同必有相符極成，故亦過攝。唯違於他，總非過攝，本害他故。此說決定自語相違，亦有兩俱、隨一、全分猶預自語相違，恐繁且止。至不成中當具顯示。

If it is based on scripture that it is called 'one's own words,' there are also two kinds of four permutations here: complete and partial. As for the complete four permutations: there is contradicting one's own words and not the other's, as when a Lokāyata says to a proponent of emptiness: 'The four great elements are not real.' They maintain that the four great elements must not be unreal, and if they say they are unreal, they must not be the four great elements, so it contradicts their own scripture and thus their own words, not the other's. There is contradicting the other's words and not one's own, as when a Buddhist says to a Sāṃkhya: 'That self of yours is not an experiencer.' The self they speak of must not be a non-experiencer, and if it is a non-experiencer, it must not be that self of theirs, so it contradicts the other's scripture and the other's words, not one's own. There is contradicting both one's own and the other's words, as in 'all words are false.' It is only when relying on contradiction with scripture that these various permutations exist; therefore, this partial permutation is also precisely the earlier partial contradiction with one's own scripture, which should be understood by analogy. Among these two sets of four permutations, contradicting oneself and contradicting both are all subsumed under this fault. Among those contradicting both, contradicting the other is not a fault, but contradicting oneself is an error; hence this is simply called contradicting one's own words. Although not contradicting either is not subsumed under this fault, when both agree there must be the fault of proving what is already established (siddhasādhana), so it is also subsumed under fault. Contradicting only the other is not subsumed under fault at all, because the original aim is to refute the other. This explains decisive contradiction of one's own words; there are also both-accepted, one-sided, complete, and doubtful contradictions of one's own words, but for fear of prolixity we shall set them aside for now. They will be fully shown when we come to the unestablished reasons (asiddha).