The latest issue (November 6, 2008) of the New York Review of Books contains an article by that irrepressible mountebank, Harold Bloom of Yale University. This piece is entitled "The Glories of Yiddish."
Bloom's comments derive from a new edition of a book first published in translation in 1940. Max Weinreich, the author, had died in 1969 without making any substantial revisions. As such, the book can hardly reflect recent advances and controversies in scholarship. On this basis, however, Bloom makes various debatable assertions about the origins and nature of Yiddish, which I won't attempt to replicate.
He quotes a poem from Jacob Glatshteyn about his arrival in New York City in 1919. This poem consists of 113 words, of which only 8 are NOT German. Compare English where only an estimated 16 per cent of the vocabulary is Anglo-Saxon--a proportion that is close to the reverse. In any event, the massive presence of foreign loan words, the majority from Romance, does not alter the fundamental nature of our language, which remains Germanic. Ditto Yiddish. For political reasons, though, one tends to limit this fundamental Germanness with regard to Yiddish. That is just PC nonsense.
In addition to the vocabulary, which is overwhelmingly Germanic with small admixtures of Slavic and Hebrew, there is the matter of syntax, always the most decisive marker in the classification of languages. Consider the familiar Yiddish refrain in the delightful song popularized by the Andrews Sisters: "Bei mir bist du sheyn." Obviously, this utterance corresponds to the High German "Bei mir bist du schön." With a minor shift in pronunciation the vocabulary is just the same. The word order is also revealing, for the Yiddish expression follows the familiar and distinctive German rule in declarative sentences: the verb must always be in the second place. Such a rule does not occur in Hebrew or Slavic languages.
Further to illustrate the point, here is a sentence from Glatshteyn's poem: "Der oyberhar hot mit dem himelbloy di gantse erd arumgeringelt un nito keyn retung." Setting aside the idiosyncracies of transcription of Yiddish into English, this is simply the German "Der Überheer hat mit dem Himmelblau die ganze Erde herumgeringelt und nicht kein Rettung." Vocabulary and syntax correspond exactly.
The truth is that Yiddish is not an autonomous language, but a nonstandard variant of High German. It is closer to High German than are either Plattdeutsch or Swiss German. Revealingly, the Yiddish word for "to translate" is fartaytshn, to Germanize.
As with all sorts of languages, from Sumerian to Old Provençal, most people will know about the glories of Yiddish only through translation. Bloom is resigned to this. "The vibrant Yiddish language, fused and open, questioning and celebrating, someday soon will be no more."