抄録
In view of the unsatisfactory state of the mechanism that the Neogrammarians advocated, Wang (1969) proposed the theory of lexical diffusion, within which it is assumed that a phonological change operates on words severally at a time, rather than on the phoneme per se. Several significant issues are discussed within the perspective of lexical diffusion: the interaction of phonetic factors and word frequency in the eModE u shortening; the processes of language acquisition of the three children who were learning their first fifty words; and the language relationship. We critically introduce genetic subgroupings of the dialects or languages by tree diagrams. Then, basing on large quantities of data on current reflexes of 7 ME long vowels, we propose a method of dynamic dialectology that better unifies the study of language in its temporal and spatial aspects.
