Q: the 'only six' argument

[Larry Trask]

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This is a very general question on comparative linguistics.

Quite often, in my reading, I've come across a statement of the
following type:

        "The presence of only six good matches between two languages
        is enough to show that the languages must be genetically related."

I've seen this many times in various forms, but I've never been alert
enough to take notes.  Now, a couple of things strike me.

First, the number is always different.  Six is the smallest I've
ever seen, but I've also seen 15, 50 and various other numbers.

Second, the expression 'good matches' is never defined, and I have
no idea if it means anything beyond 'matches that impress me
personally'.

So, my question: does anybody believe that any version of this
statement is valid?  More precisely, do we have a number N and
a set of criteria C such that the existence between two languages
of N matches satisfying criteria C is enough to guarantee that
the languages must be related?


Larry Trask
COGS
University of Sussex
Brighton BN1 9QH
UK

larryt at cogs.susx.ac.uk

Tel: 01273-678693 (from UK); +44-1273-678693 (from abroad)
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