Sino-Tibetan Negation and the Case of Galo: Explaining a Distributional Oddity in Diachronic Terms

While the vast majority of Sino-Tibetan (=Trans-Himalayan) languages have a pre-head predicate negator, Tani is one of a small handful of subgroups whose languages display an exclusively post-head negator. This negator, furthermore, is somewhat unusual in having both derivation-like and inflection-like properties, and in occupying an 'intermediate' position between derivations and inflections in the predicate stem. This article proposes a common explanation for both facts, by hypothesizing that reanalysis of an AUX-final serial verb construction as a single predicate word has resulted in realignment of an earlier pre-head auxiliary negator as a predicate suffix with leftward scope over the predicate stem. This is similar to another channel found in some Tibeto Burman languages in which a prefixal negator fuses with a clause-final auxiliary to become a suffix (as in Kuki-Chin and 'Naga'); however, I argue it to be ultimately somewhat different. These arguments are made on the basis of a more comprehensive description of negation in Galo (Tibeto-Burman > Tani, Eastern Himalaya) than was provided in Post (2007); as such, a second goal of the paper is to contribute to the typology of negation in Asian languages more generally.