H₂e-conjugation theory

The h₂e-conjugation theory adds a third conjugation to the two generally accepted conjugations of the Proto-Indo-European language (PIE), the thematic and athematic conjugations.

The symbol h₂ refers to a particular example of a class of sounds known as "laryngeals" in the theory of PIE linguistics.

Proposed by Jay Jasanoff in 1979 and presented in its most elaborate form in Jasanoff (2003), the evidence for the "new" verbal conjugation in PIE is based on the attested existence of the similar ḫi-conjugation in Hittite and other Anatolian languages. Whereas the Anatolian ḫi-conjugation has traditionally been seen as an innovation in the Anatolian branch of the Indo-European family of languages, Jasanoff presents evidence and arguments to place it as a conjugation already established in PIE proper.

The following table serves to give an understanding of the problem that the theory tries to solve.

The origin of the Hittite mi-conjugation (in the singular of the present indicative active) is not controversial. It can easily be identified as a descendant of the corresponding forms in the ancestral PIE language.

The question is, where does the ḫi-conjugation come from (represented in the table as question marks)? A very common solution (Eichner and others) has been to derive it from the PIE perfect. The second most common candidate has been the PIE middle (Rozenkranz, Kuryłowicz). (Why the PIE perfect and middle endings resemble each other so much is a major question in itself, and of course of great interest vis a vis the Hittite ḫi-conjugation). Deriving the Hittite ḫi-conjugation directly from the PIE thematic presents (like Couvreur did) involves huge problems, but that there is some connection seems very probable (in line with Pedersen and Watkins).

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