On the PIE root-structure constraint prohibiting repeated consonants

  • Paul S. Cohen
  • Benji Wald


This paper confronts and resolves the problem of apparent exceptions to the constraint prohibiting the co-occurrence of identical consonants in both syllable margins of the PIE root: schematically, †… Ci … E … Ci …, where † indicates the prohibition of the root structure following it, Ci = the identical consonant, E = the ablauting vowel, and … = optional additional consonants in the syllable margins. In advancement of previous work addressing this problem — most recently exemplified in Cooper (2009), Corbeau (2013) and Weiss (2020) — it eliminates several potential exceptions to the constraint and proposes that, once a cross-linguistic absence-of-contrast principle is taken into account which determines the relation of laryngeal features (glottalization, aspiration, and voicing) to the syllable margins that contain them, no clear-cut exceptions remain.