The pramāṇas / Postulation
Postulation, arthāpatti (अर्थापत्ति)
Summary
Postulation is a means Mīmāṃsā (मीमांसा) counts and Nyāya (न्याय) does not count apart. Something is known because otherwise a fact already known would be impossible. Nyāya (न्याय) folds that move into inference. The page says the difference. It does not invent a sūtra (सूत्र) in which Gautama names arthāpatti (अर्थापत्ति) as a fifth.
नेपालीमा
अर्थापत्ति मीमांसाले गन्ने र न्यायले अलग नगन्ने साधन हो। पहिले जानिएको तथ्य नत्र असम्भव हुने भएकाले केही जानिन्छ। न्यायले त्यो चाल अनुमानभित्र पर्छ भन्छ। पृष्ठले भिन्नता भन्छ। पृष्ठले गौतमले अर्थापत्तिलाई पाँचौँ साधन भनेको कुनै सूत्र आफैँ गढ्दैन।
artha (अर्थ) is a fact. āpatti (आपत्ति) is a coming-about. A further fact is supposed because the facts in hand would not stand otherwise.
The classroom picture is not a sūtra (सूत्र) in this book. Devadatta (देवदत्त) is fat, and he is not seen to eat by day. The fatness stands if he eats at night. That supposition is the postulation. Another supposition could fill the same gap. Nyāya (न्याय) presses that point. Mīmāṃsā (मीमांसा) counts the step anyway.
Two kinds
The Mīmāṃsā (मीमांसा) books name two. dṛṣṭārthāpatti (दृष्टार्थापत्ति) runs from what is seen, as with the fat man. śrutārthāpatti (श्रुतार्थापत्ति) runs from what is heard, when a sentence does not yield a sense until a word is supplied. Jaimini (जैमिनि)'s sūtra (सूत्र) does not open with this pair. The pair belongs to the later Bhāṭṭa (भाट्ट) and Prābhākara (प्राभाकर) books. Both of those schools count postulation as its own means.
न्याय Nyāya
Nyāya (न्याय) 2.2.1 is the objection that postulation, with three other names, forces the means to be more than four. 2.2.2 answers that postulation is nothing other than inference. 2.2.3 raises the objection that postulation is inconclusive, anaikāntika (अनैकान्तिक): it does not stay on one side. 2.2.4 answers it. Nyāya (न्याय) keeps postulation valid, but folds it into inference.
The lines after 2.2.4 keep that argument. This page stops at the definition of the step and at those four sūtras (सूत्र). Sāṅkhya (साङ्ख्य)'s three, at kārikā (कारिका) 4, leave no slot with this name. Every means, the verse says, already stands by the three.
न्यायसूत्र २.२.३ ले अर्थापत्ति अनैकान्तिक हो भन्ने आपत्ति उठाउँछ। २.२.४ ले त्यसको जवाफ दिन्छ। न्यायले अर्थापत्तिलाई मान्य राख्छ, तर अनुमानभित्र राख्छ।