From: markrose@spss.com (Mark Rosenfelder)
Subject: Re: Correlation Lengths of Language Changes
Organization: SPSS Inc.
Date: Mon, 11 Jan 1993 20:14:56 GMT

In article <Jan.8.21.14.52.1993.18293@pilot.njin.net> hubey@pilot.njin.net 
(Mark Hubey) writes:
>A. How do we tell apart languages which differ by the smallest 
>degree i.e. very close dialects or idiolects.
>	ANS: nano level, phonemes, formants, phoneme level.
>	No need to check micro, midi, macro levels.
>
>B. How do we tell apart languages which differ greatly?
>	ANS. macro-level. Chinese is tonal. Uralic-Altaic
>	have vowel harmony. Chinese is strictly positional. [...]
>	No need to check for phonemes or words. If the words
>	match, they're borrowed. How do we reach this 
>	conclusion ? 
>
>There are priority levels. If there's no 'match' at the
>upper levels, lower level matches are borrowings.
>
>If the languages are very close you only try nano level. If
>they're far apart, macro-level will do. How about if
>they somewhat resemble each other or you're not sure ?
>Well, it seems that micro-midi level become important.
>Doesn't  this seem logical ?

Theories generally aim to explain the data, not to be "logical"; but we'll
let that pass.  Your proposal is on the table: to test relatedness of
languages, use the "nano level" (phonology and morphemes) for closely related 
languages, the "macro level" (typology) for those that are far apart,
the "micro-midi level" (words, morphology, syntax) for those in between.

Of course, the first problem here is circularity: "If the languages are
very close you only try nano level."  How do you know they're close?
If you already know, what is this procedure intended to accomplish?

Next, since you have different evaluation procedures for "close" and for
"far apart" languages, what do you do when the procedures give conflicting
results? 

>To say that infixing, postifixing, prefixing are not important
>because Bengali is postfixing and English is both pre and post
>and infixing is circular logic. Who says Bengali did not borrow words
>and that it wasn't originally agglutinative and maybe derived
>from proto-Dravidian ? AT what level are the comparisons being 
>made ? Which aspects of language persist longer ?
>
>To say that Irish, French and English differ as to VSO, SVO
>etc so that it's unimportant is circular logic. In fact it
>neatly divides them up (at the micro-midi level) into
>Celtic, Italic and Germanic. 

I'm afraid your proposal very quickly runs into some intractable data here.
Namely: Typology can change much quicker than phonology does.  The slow
and overwhelmingly attested change from Latin to French (etc.) shows this.
Latin is largely a verb-final language; French is basically SVO.  (Caveats 
apply on both sides; Latin had of course fairly free word order; while spoken
French is arguably turning into a different beast.)  Or consider how 
the highly inflected Anglo-Saxon turned into highly isolating modern English.
Hock (_Historical Linguistics_) also has a nice description of important
typological changes in Sanskrit and its descendants.

There's also Sprachbunden to worry about; unrelated languages which happen
to be geographically similar can come to share similar syntactic features,
while retaining separate vocabularies.  

The comparative method's reliance on lexical items and paradigms in 
determining the descent of languages is thus eminently reasonable; these are 
the things that change the slowest in a language ("slowest" here resting not 
on additional linguistic theory, but on the observed history of real 
languages).