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Dignāga on trairūpya Reconsidered: A Reply to Prof. Oetke 261 second characteristic. If we restrict it in the way "tattulye (=sapakşe) lingasya sadbhāva eva", then the domain of the property to be proven or inferred (sādhya / anumeya-dharma) is restricted by the domain of linga. In other words, the former is pervaded by the latter. In that case, linga is deviant or inconclusive (vyabhicărin / anaikāntika) in respect to what is to be proven (sādhya) and it cannot be regarded as valid.
linga
sādhya
If we restrict the anvaya formula in the way "tattulya (=sapakşa) eva lingasya sadbhāvaḥ”, then the domain of linga is restricted by the domain of the property to be proven. In this case, linga is neither deviant nor inconclusive and it is a valid inferential mark.
sādhya
linga
In the case of Hetu No. 2 the domain of sādhyadharma (=anityatva) and the domain of hetu (=kặtakatva) are co-extensive but at least the domain of hetu does not deviate from the domain of sādhyadharma. Therefore, it can be regarded as a special case of hetu's being restricted by sādhyadharma.
In the case of Hetu No. 8 it is quite clear that the domain of hetu (=prayatnānantariyakatva) is restricted by the domain of sādhyadharma (=anityatva). Consequently, it is regarded as a valid hetu.
