--- You wrote:
If I'm understand Beckwith's disassociation of Koguryo(ic) and Japanese from other Altaic languages, does this imply that Tungusic languages are only in some incidental way connected to "Altaic" languages at all? Does it mean that if there is an Altaic family it really has only two branches --Turkic and Mongolic? Does it leave the Tungusic languages as a free-standing language group?
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Hi Professor Crossley,
The Tungusic languages have always been part of the Altaic language family - one of the branches in a dendritic classification.  It's the status of Korean and that of Japanese that are disputable.  In the early years, Korean and Japanese were grouped together with the Altaic languages and identified with the Tungusic languages.  The Korean-Japanese-Tungusic link is not clear and I doubt we can prove that Korean or Japanese were part of Tungusic.  I think Roy Andrew Miller once attempted to argue for the Altaic status of Japanese.  Some have called Japanese a language isolate, like Korean.  It'll be interesting to see what others make of the relation between these languages.

Best,
Wayne