On Tue, 20 Nov 2012 09:15:29 -0800
Garth Wallace <[log in to unmask]> wrote:

> On Tue, Nov 20, 2012 at 8:24 AM, David McCann
> > A [indef specific] nice man helped me out.
> > *A bus [indef non-specific] ran him over.
> > Polynesian languages would use different articles here.
> I'm not sure what you mean by non-specific. Do you mean like in gnomic
> sentences?

I'm using "specific" as a linguistic term meaning "known to the speaker
but not known to the hearer", as distinct from "indefinite" meaning
simply "unknown to the hearer".

As I said, Polynesian languages have a specific / nonspecific contrast
in articles instead of a definite / indefinite one. The concept also
shows up in indefinite pronouns/adjectives:
Someone [specific] called while you were out: you'll never guess who it
Someone [indefinite] called while you were out, but she wouldn't leave
her name.
In English "someone" serves for both, but "some" cannot be specific.
Latin distinguishes "quidam" and "aliquis", while some languages (e.g.
Hausa, Quechua) lack a specific indefinite.

I was a bit over the top with my "*A bus ran him over"; I should have
written "?A bus ran him over": odd, but not totally ungrammatical.