Ivšić's law or Stang's law is a Common Slavic accent law named after Stjepan Ivšić and Christian Schweigaard Stang who both independently discovered it. It explains the origin of the so-called Proto-Slavic neoacute accent occurring in the accent paradigm b as retractive from the following syllable. It was independently discovered by Ivšić in 1911, and 46 years later by Stang.
Retraction from stressed weak yer
During the Late Common Slavic period, the short vowels *ь and *ъ (known as yers, also written *ĭ *ŭ) developed into "strong" and "weak" variants according to Havlík's law. The accented weak variants could no longer carry an accent which was thus retracted onto the preceding syllable. That syllable gained a rising neoacute accent. It is denoted with a tilde diacritic ⟨◌̃⟩ on historically "long" syllables (*a, *i, *u, *y, *ě, *ę, *ǫ, *VR), and with a grave accent ⟨◌̀⟩ on a historically "short" syllables (*e, *o, *ь, *ъ).
In conservative Serbo-Croatian dialects of Čakavian and Old Štokavian (e.g. Slavonian) this neoacute is preserved as a separate tone, distinct from the old acute and circumflex. Ivšić designated the long neoacute in Čakavian with the same circumflex symbol as the Lithuanian circumflex, due to their phonetic similarity.
Retraction from medial circumflexed syllables
Retraction also occurred on medial long circumflexed (i.e. non-acuted) syllables, e.g. on verbs in *-iti. On the basis of attested forms nȍsīte, vrãtite Ivšić assumed earlier forms of *nosȋte *vortȋte which would also yield neoacute by retracting the long circumflex accent onto the preceding syllable. This retraction is uncontroversial if the preceding syllable is long - in case of short preceding syllables, it is generally accepted, but some argue that it's analogical to long neoacute in individual (mostly West Slavic) languages.
Additionally, Ivšić's law explains the acute accent on certain jā-stem nouns such as sũša (Slavonian Štokavian speeches), vȍlja (with shortened neoacute).
Borrowings from other languages show that Ivšić's law operated after Dybo's law, and had the effect of partially reversing it. Compare:
- PSl. *kȁrlju 'king' (originally the name of Charlemagne) > (Dybo's law) *karlju̍ > (Ivšić's law) *kãrlju > Čakavian krãlj.
- Matasović, Ranko (2008), Poredbenopovijesna gramatika hrvatskoga jezika [A comparative-historical grammar of the Croatian language] (in Croatian), Zagreb: Matica hrvatska, ISBN 978-953-150-840-7
- Ivšić, Stjepan (1911), "Prilog za slavenski akcenat" [A contribution to Slavic accent], Rad JAZU (in Croatian) (187): 133–208
- Stang, Christian (1957), Slavonic accentuation, Oslo
- Kapović, Mate (2008), "Razvoj hrvatske akcentuacije", Filologija (in Croatian) (Zagreb: Hrvatska akademija znanosti i umjetnosti) 51: 1–39
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