Abstract: In early excavated texts such as oracle bone inscriptions, bronze inscriptions, and Warring States bamboo and silk manuscripts, sporadic examples can be found where labial characters and lingual characters are used interchangeably in phonetic series or as phonetic loans. Scholars in the past have explained these phenomena either by positing consonant clusters or by invoking dialectal variation. This study finds that the alternation between labials and linguals not only existed in Old Chinese but also occurs in modern Chinese dialects and minority languages. It represents a natural sound change, possibly related to auditory confusion resulting from phonetic similarity.

Key words: Excavated Ancient Chinese Texts, Labial and Lingual Sounds, Harmony and Interchange, Phonological Interpretation