New Light on an Old Hypothesis:
Hirt's Law and the Origin of the Slavic Accentual Classes
Perhaps the biggest discrepancy between the Baltic and Slavic accentual systems is that those Slavic languages which have preserved lexical accent (e.g. Russian and Serbo-Croatian) exhibit three classes of nominal and verbal stems, namely accented, unaccented, and postaccenting, whereas Lithuanian contrasts only underlyingly accented and unaccented stems. Although it is generally agreed that Baltic and Slavic have undergone a period of common development in their accentual systems, the prehistory of these accentual classes, and their relation to the system reconstructible for Proto-Indo-European (PIE), has not yet been fully clarified.
Dybo (1981:18ff., with refs.) considers the postaccenting class of Slavic to be an innovation: in pre-Proto-Slavic, stems which were underlyingly accented on a non-acute syllable (i.e. either a long vowel or diphthong with "circumflex" intonation, or a short vowel) advanced their stress to the following syllable, thus resulting in the attested postaccenting type of e.g. Russian stol 'table', stol-á, -ú, -óm, -é, etc. This analysis, which has been accepted by most researchers in Balto-Slavic accent today (cf. Dybo et al. 1990:38ff., Lehfeldt 1993:44ff.), explains the complementary distribution of intonation in Proto-Slavic accented and postaccenting stems: the former retain their accent on an acute syllable head, whereas the latter have advanced it from a circumflex or short stem vowel to the following syllable. Yet Dybo's Law fails to account for a significant peculiarity: both in Lithuanian and in reconstructed Proto-Slavic, underlyingly accented polysyllabic stems are always accented on the stem-final syllable.
I propose that the Slavic postaccenting class is not an innovation, but directly continues the inherited oxytonic type of ancient Greek zugón 'yoke' or Vedic Sanskrit devá- 'god'. Instead of a rightward accent shift, the complementary distribution discovered by Dybo may just as easily be explained as the result of a retraction of postaccenting stress to a preceding "acute" syllable head. Such a hypothesis immediately accounts for the otherwise unmotivated restriction of underlying accent to the final syllable of polysyllabic stems in Baltic and Slavic.
This retraction recalls the sound change proposed over a century ago by Hirt, according to which PIE oxytonic stems retracted their stress to a preceding long vowel — in today's terms, a vowel or diphthong plus tautosyllabic laryngeal, i.e. *VH or *VRH. As there is universal agreement that tautosyllabic laryngeals are the major source of the Balto-Slavic "acute", Hirt's Law accounts at once for the complementary distribution of acute vs. circumflex intonation in accented vs. postaccenting stems. The alleged counterexamples to the law which had led to its gradual abandonment or deemphasis over the last century find a ready explanation within the brackets-and-edges model of prosodic computation (cf. Idsardi 1992, Halle and Idsardi 1995, Halle 1997): only sequences of the form * (*, where the first stress-bearing head is acute, undergo retraction to (* *, while unaccented sequences * * remain as such, e.g. *suÌnu- 'son'.
This revised statement of Hirt's Law thus precludes the need for Dybo's forward shift in Slavic. The oxytonic class of PIE o- andáÌ-stems has been preserved in Slavic and possibly also Old Prussian, and its elimination in Lithuanian is due to later East Baltic innovations.
Dybo, Vladimir A. 1981. Slavjanskaja akcentologija: opyt rekonstrukciji sistemy akcentnyx paradigm v praslavjanskom. (Akademija Nauk SSSR, Institut Slavjanovedenija i Balkanistiki.) Moscow: Izdatel'stvo Nauka.
—, G. I. Zamjatina, S. L. Nikolaev. 1990. Osnovy slavjanskoj akcentologii. Moscow: Izdatel'stvo Nauka.
Halle, Morris. 1997. On stress and accent in Indo-European. Language 73:2, 275-313.
— and William Idsardi. 1995. General properties of stress and metrical structure. The Handbook of Phonological Theory, ed. by John Goldsmith, 403-43. Oxford and Cambridge, MA: Blackwell.
Idsardi, William. 1992. The Computation of Prosody. Ph.D. dissertation, MIT.
Lehfeldt, Werner. 1993. Einführung in die morphologische Konzeption der slavischen Akzentologie. (Vorträge und Abhandlungen zur Slavistik, Band 23.) München: Sagner.