8.4.31
हलश्च इजुपधात्
Operational rule vidhi
The कृत् affix, coming after a verb, which begins with a consonant and has a penultimate इच् vowel, changes optionally its न् , which is preceded by a vowel, into ण् , when it comes after उपसर्ग having a cause of change.
Word by word (padaccheda)
Left context pañcamī · ekavacanaIndeclinable च avyayaLeft context - pañcamī · ekavacana
- Left context Pañcamī (5th case): "after X", the operation applies to what follows (1.1.67 तस्मादित्युत्तरस्य). Also used for limits and sources.
- Indeclinable An avyaya such as च "and", वा "optionally", न "not".
Dotted words are technical terms, dashed ones pratyāhāras (names for classes of sounds or affixes). Hover or tap one to see its card.
Full reading
च -
Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.
Commentary
The कृत् affix, coming after a verb, which begins with a consonant and has a penultimate इच् vowel, changes optionally its न् , which is preceded by a vowel, into ण् , when it comes after उपसर्ग having a cause of change.
The phrase कृत्यचः is understood here. Thus प्रकोपणम् or प्रकोपनम्, परिकोपणम् or परिकोपनम् ॥
Why do we say हलः 'beginning with a consonant'? Observe प्रेहणम् and प्रोहणम् where the change is obligatory, under 8.4.29. These are from ईह चेष्टायाम् and ऊह वितर्के ॥
Why do we say इजुपधात् 'having a penultimate इच् vowel'? Observe प्रवपणम् and परिवपणम्; no option.
By the rule कृत्यचः the change was obligatory, this rule makes it optional.
The न of the krit-affix must come after a vowel, otherwise there will be no change. See परिभुग्नः ॥
The word हलः in the sutra should be interpreted as हलादेः, and not as ordinarily "after what ends in हल्" ॥ For an इजुपधा verb implies that it ends with a consonant, and so the employment of the word हलः in the text would have been useless had it meant हलन्तात् ॥
Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.