The Old Chinese origin of Middle Chinese voice sibilants z/ʑ

This paper discusses the Old Chinese origin of voiced sibilants zand ʑin Middle Chinese. First, based on careful examination of Guǎngyùn (广韵) and other texts, we argue that, although the distinction between voiced affricates and fricatives was largely kept in the Guǎngyùn system, in some words the voiced affricates dz-/dʑhad already merged into fricatives z-/ʑdue to copying from other texts and/or sound change. Second, we argue that zand ʑin Middle Chinese are either in complementary distribution or show free variation in some occasions. Therefore, they had one single origin (/z/) before the onset of the sound change z> ʑ-. Based on these arguments, we have carried out a detailed analysis of the xiéshēng series and found four different origins for /z/. They are *r-j-, *s-ɢ-, *z-, and *s-drespectively.