Principled Comparative Method - a new tool

[Sean Crist]

On Thu, 12 Aug 1999, Jon Patrick wrote:

> The idea is that the distance between languages is represented by the
> series of changes that occur to a large set of words in moving from
> their parent form to their daughter forms, so that distance apart is not
> measured between the daughter languages but rather by their distance
> from their parent. We feel this better represents the real world
> process.
> Our data has to be the word set in the parent form (reconstructed words
> or real words) and then one word set for the each daughter language and
> the set of phonological transformation rules between each parent and
> daughter for each word in their chronological sequence. Hence we are
> modelling the rules and their sequence of application for each word. The
> extent to which any of this information is hypothetical merely defines
> the hypotheses one is comparing, but importantly it does not effect the
> computational method we apply to this data.

This post certainly caught my interest, because I've got various ideas
myself about how computers could be better used in language
reconstruction.  In a very general way, I think we have some of the same
interests.

I do have some comments about your specific approach.  If I understand
correctly, you're measuring language 'distance' at least partially in
terms of how many historical phonological rules a language has undergone
since it first diverged from some reconstructed ancestor: the more rules,
the greater the distance.  (I hope I haven't just plain misunderstood; if
so, the following may not apply.)

I think the basic problem your approach raises is this: how do you count
historical phonological changes?  For example, is the Great Vowel Shift in
English one rule, or a dozen?  It looks like your distance measure will
depend a great deal on what choices you make on such questions.

The rule count is going to depend in part on what phonological theory
you're working in.  A traditional historical grammar of a language often
lists a multitude of small rules which a modern theory can conflate into a
shorter list.  Exactly how short you can make the list partly depends on
what phonological theory you're working in. There may indeed be no
phonological rules at all in the traditional sense;  phonological change
could all be just the reranking of constraints, which is what I'm assuming
in my in-progress dissertation.

I'll respond to your question about an online database of Indo-European
under a separate cover.

  \/ __ __    _\_     --Sean Crist  (kurisuto at unagi.cis.upenn.edu)
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