प्रकृतिभावप्रकरणम्

Covers SK 90–110 (21 sūtras): all present.

Acsandhau prakṛtibhāvaḥ — outline (p04, SK 90–110, all 21 sūtras)

The exemptions from vowel-sandhi: which vowels stay in their prakṛti (own form) instead of combining. For every rule the "work" is a form left standing apart — a pragṛhya ī that does not become y, a pluta a³ that takes no savarṇadīrgha. Grouped by which item is exempt and how: the master rule (A); the optional ik/ak retention (B); the source rules that first make the pluta (C); the boundary where a pluta stands down (D); the pragṛhya roster of 1.1.11–19 (E); and the two residual sandhi rules that supply alternatives (F). Order tracks SK closely; the one reorder is 108, pulled past 109 into F, since it is a tripādī va-rule (8.3.33), not part of the 1.1.11–19 pragṛhya roster.

A. The master rule — pluta & pragṛhya vowels invariably block sandhi — running example: harī etau, ehi kṛṣṇa³ atra

• 90 plutapragṛhyā aci nityam 6.1.125 — pluta (protracted, "³") and pragṛhya vowels invariably (nityam) stay in prakṛti — no sandhi — when a vowel (ac) follows; this governs the whole prakaraṇa (the pluta defined by 93–97, the pragṛhya by 100–109). In harī etau the pragṛhya ī does not go to yaṇ y; in ehi kṛṣṇa³ atra the pluta a³ takes no savarṇadīrgha before the following a. The point of nityam: precisely this bare prakṛtibhāva must win, blocking the rival prakṛtibhāva-with-shortening of 91 (else paratva would let the later Śākala rule in).

B. The pada-final ik/ak kept (Śākalya's optional retention + shortening) — running example: cakri atra, brahma ṛṣiḥ

• 91 iko 'savarṇe śākalyasya hrasvaś ca 6.1.127 — in Śākalya's view a pada-final ik (i u ṛ ḷ) before a dissimilar (asavarṇa) vowel optionally stays in form and is shortened. cakrī atra → the ī stays and shortens → cakri atra (no yaṇ); the non-Śākalya alternative gives yaṇ → cakryatra. Two vārttikas fold in: na samāse (not in a compound: vāpyām aśvaḥ → vāpyaśvaḥ) and siti ca (not before a sit affix: pārśvam). Excluded by "pada-final" (padāntāḥ): gauryau.
• 92 ṛtyakaḥ 6.1.128 — carrying forward hrasva + prakṛtibhāva from 91, but now for a pada-final ak (so a/ā too, not just ik) before ṛ. brahmā ṛṣiḥ → the ā shortens and stays → brahma ṛṣiḥ, blocking the ād-guṇa that would give brahmarṣiḥ. Applies even in a compound (the na samāse vārttika does not reach here): sapta ṛṣīṇām → saptaṛṣīṇām (vs. guṇa saptarṣīṇām). Excluded by padānta: ā ṛcchat → ārcchat (the ā is not pada-final).

C. Making the pluta — the source rules that protract a sentence-final vowel — running example: devadatta3

• 93 vākyasya ṭeḥ pluta udāttaḥ 8.2.82 — adhikāra heading (no worked form of its own): the ṭi (final-vowel segment) of a sentence becomes pluta and udātta; "vākyasya" confines it to the sentence's last pada, and "ṭeḥ" secures pluta even for consonant-final sentences (grāmaṃ gacchāgnici3t). Supplies "pluta of the sentence-final ṭi" to 94–97.
• 94 pratyabhivāde 'śūdre 8.2.83 — in a return-greeting addressed to a non-śūdra (dvija), the sentence's ṭi is pluta+udātta. Reply āyuṣmān bhava … devadatta3 — the final a of the name protracted. Vārttikas fold in: striyāṃ na (not to a woman: bho āyuṣmatī bhava gārgi, no pluta) and bho-rājanya-viśāṃ vā (optional for bhoḥ and kṣatriya/vaiśya names: bhoḥ3, indravarma3n, indrapālita3).
• 95 dūrād dhūte ca 8.2.84 — and in address (sambodhana) from afar, the sentence's ṭi is pluta. saktūn piba devadatta3 — the final a of devadatta protracted (sambodhana, not mere calling, so it works even with no explicit calling-word).
• 96 haiheprayoge haihayoḥ 8.2.85 — when the vocative particles hai/he are employed (in far-calling), the pluta falls only on hai/he (niyama). he3 rāma, rāma hai3 — the ai/e protracted; the restriction keeps pluta off another word's final (contrast the free choice of 97), and "prayoga" lets it hit hai/he even when they are non-final.
• 97 guror anṛto 'nantyasyāpy ekaikasya prācām 8.2.86 — (Eastern view) in far-calling, each single guru vowel other than ṛ, even a non-final one, is optionally pluta, one at a time (ekaika = alternation). de3vadatta / devad3atta / devadatta3. "guru" excludes the light a after v; "anṛtaḥ" excludes ṛ (so kṛṣṇa3, only the final a). The yoga-vibhāga of prācām makes every pluta optional (retiring the "sarvaḥ plutaḥ… vibhāṣā" vārttika).

D. When the pluta stands down — a pluta made to behave like a non-pluta — running example: suśloketi, cinuhīti

• 98 aplutavad upasthite 6.1.129 — when an upasthita (a non-Vedic "iti") follows, a pluta acts like a non-pluta (aplutavat) — so sandhi does run. suśloka3 iti → aplutavat → ād-guṇa → suśloketi. The word "vat" cancels only the pluta's prakṛtibhāva operation, not the protraction itself, so a pragṛhya-based pluta stays audible: agnī3 iti.
• 99 ī3 cākravarmaṇasya 6.1.130 — (Cākravarmaṇa's view) a pluta ī3 before any vowel optionally behaves as apluta. cinuhī3 iti / cinuhīti; cinuhī3 idam / cinu hīdam — the option (vibhāṣā) holds in both, before "iti" and before any other vowel.

E. The pragṛhya roster (1.1.11–19) — which forms are pragṛhya, so 90 keeps them apart — running example: harī etau, viṣṇū imau

• 100 īdūded dvivacanaṃ pragṛhyam 1.1.11 — a dual (dvivacana) ending in ī/ū/e is pragṛhya (saṃjñā). harī etau, viṣṇū imau, gaṅge amū (the e blocks ay), pacete imau (tadanta-vidhi: the dual ending in e, not being e itself, still qualifies) — each pragṛhya, so by 90 prakṛtibhāva, no yaṇ/ay. Note: maṇīva is maṇī + particle va ("like"), not a dual pragṛhya.
• 101 adaso māt 1.1.12 — the ī/ū of adas that follow its m are pragṛhya (extends the saṃjñā where 1.1.11 cannot reach). amī īśāḥ (this ī is a plural, so 1.1.11's dual-requirement fails and this rule supplies it); rāmakṛṣṇāv amū āsāte. "māt" blocks the carried-forward e, so amuke 'tra (e after k, not m) is not pragṛhya.
• 102 śe 1.1.13 — a form ending in the (Vedic) affix śe is pragṛhya. asme indrābṛhaspatī — the e of asme stays, no ay-sandhi.
• 103 nipāta ekāj anāṅ 1.1.14 — a single-vowel particle (ekāc), except āṅ, is pragṛhya. i indraḥ, u umeśaḥ — the particles i/u stay apart. An aṅit ā is pragṛhya (ā evaṃ nu manyase, ā = resumed-sentence/recollection sense); the ṅit āṅ ("a little," kriyāyoga, maryādā, abhividhi) is excluded → ā uṣṇam → guṇa → oṣṇam.
• 104 ot 1.1.15 — an o-final particle (nipāta) is pragṛhya. aho īśāḥ — the o stays, no av-substitution.
• 105 sambuddhau śākalyasyetāvanārṣe 1.1.16 — (Śākalya, optional) the vocative-occasioned final o is pragṛhya before a non-Vedic "iti". viṣṇo iti (pragṛhya, stays) vs. viṣṇav iti (non-pragṛhya, v-substitution). "anārṣe" excludes Vedic usage: brahmabandhav ity abravīt (ārṣa → yaṇ applies).
• 106 uñaḥ 1.1.17 — the particle uñ (= u) is optionally pragṛhya before "iti" (Śākalya; "prāg-uktam," the earlier saṃjñā carried in). u iti (pragṛhya, stays) vs. v iti (yaṇ). [The SK/Bālamanoramā treats the received text as the single sūtra uñ ūṃ split into 1.1.17 + 1.1.18, precisely to yield the third form v iti.]
• 107 ūm̐ 1.1.18 — the substitute ūm̐ (long, nasalized, and itself pragṛhya) optionally replaces uñ before "iti". ūm̐ iti — pragṛhya, so prakṛtibhāva. With 106 this gives the three forms ūm̐ iti / u iti / v iti.
• 109 īdūtau ca saptamyarthe 1.1.19 — a pada ending in ī/ū that rests in locative sense (after luk of the saptamī by supāṃ suluk) is pragṛhya. somo gaurī adhiśritaḥ (= gauryām), māmakī tanū iti (= māmakyāṃ tanvām) — pragṛhya → prakṛtibhāva, no yaṇ. "artha" (vs. bare saptamyām) excludes the sense shifting inside a compound: vāpyām aśvaḥ → vāpyaśvaḥ (the ī has passed to the second member, so not pragṛhya).

F. Residual sandhi rules — a substitute where sandhi is otherwise blocked, and pausal nasalization — running example: kimvuktam, dadhiṃ

• 108 maya uño vo vā 8.3.33 — (residual; pulled here from between 107 and 109) uñ after a maY consonant optionally becomes va before a vowel — an alternative supplied because uñ, being invariably pragṛhya (1.1.14), otherwise blocks yaṇ. kimu uktam → kimvuktam; placed in the tripādī, the va-substitution is asiddha, so mo 'nusvāraḥ does not fire (no anusvāra for the m).
• 110 aṇo 'pragṛhyasyānunāsikaḥ 8.4.57 — a non-pragṛhya aṇ (a i u only, by the earlier-ṇ pratyāhāra) optionally becomes its anunāsika (nasalized) counterpart at a pause (avasāna, carried from vā … avasāne). dadhi → dadhiṃ or dadhi. The "non-pragṛhya" clause is the exemption's mirror: a pragṛhya dual agnī does not nasalize. This closes the ac-sandhi section (Bālamanoramā colophon; the pratyayamālā follows).