The Ashtadhyayi (Ạṣtādhyāyī, meaning "eight chapters") is the earliest known grammar of Sanskrit, and one of the first works on descriptive linguistics, generative linguistics, or linguistics altogether. It was composed roughly around 400 BC by the Indian grammarian Panini, and it describes the grammar of Sanskrit completely. Its mathematical structure has been compared to that of the Turing machine.

Panini's work had a phenomenal success, and later Indian grammarians were essentially reduced to the role of his commentators. His work is still used, or at least referred to, in the teaching of Sanskrit today.

Panini's grammar consists of several parts, of which the Ashtadhyayi contains the morphological rules:

• Shiva Sutras (phonology)
• Ashtadhyayi (morphology)
• Dhatupatha (lexicon of verbal roots)
• Ganapatha (lists of classes of words)

The Ashtadhyayi consists of 3,959 sutrani or rules, distributed among eight chapters, which are each subdivided into four sections or padas.

From example words in the text, and from a few rules depenting on the context of the discourse, additional information as to the geographical, cultural and historical context of Panini.

The rules

The first two sutras are transcribed thus:

1.1.1 vṛ́ddhir āT-aiC

1.1.2 aT-eṆ guṇáḥ

The capital letters and are so-called IT markers. The C and Ṇ refer to Shiva Sutras 3 and 4, forming the pratyaharas aiC, eṆ, i.e. they denote the list of phonemes {ai, au} and {e, o} respectively. The T appearing in both sutras is also an IT marker: It is defined in 1.1.70 as denoting that the preceding phoneme is not representing a list, but a single phoneme, (but encompassing all supra-segmental features (accent, nasality)), i.e. āT and aT represent {ā} and {a} respectively. The interpretation of the two sutras is thus:

1.1.1: the technical term vṛ́ddhi denotes the phonemes {ā, ai, au}.

1.1.2: the technical term guṇa denotes the phonemes {a, e, o}.

I.e. they are definitions of terminology: guṇa and vṛ́ddhi are the terms for the full and the lenghtened ablaut grades, respectively.

List of IT markers

(incomplete)

• suP nominal desinence
• Ś-IT
  • Śi strong case endings
  • Ślu elision
  • ŚaP active marker
• P-IT
  • luP elision
  • āP ā-stems
    • CāP
    • ṬāP
    • ḌāP
  • LyaP (7.1.37)
• L-IT
• K-IT
  • Ktvā
  • luK elision
• saN Desiderative
• C-IT
• M-IT
• Ṅ-IT
  • Ṅí Causative
  • Ṅii ī-stems
    • ṄīP
    • ṄīN
    • Ṅī'Ṣ
  • tiṄ verbal desinence
  • lUṄ Aorist
  • lIṄ Precative
• S-IT
• GHU class of verbal stems (1.1.20)
• GHI (1.4.7)

See also

• Sanskrit
• set and anit roots