On 28 February 2018 at 18:07, Logan Kearsley <[log in to unmask]> wrote:

> English has a distinction between restrictive relative clauses (which
> provide information necessary for identifying the referent, or which
> restrict the set of possible referents) and non-restrictive relative
> clauses (which merely provide additional background information on an
> already-determined referent set). But Russian, for example, does not
> bother with that distinction. So, while I have no idea what the
> distribution of this feature in natlangs generally is (there doesn't
> seem to be a WALS feature for it), there is clearly variation.
> In contrast, there is no way to distinguish restrictive vs.
> non-restrictive adjectives (apart from relativizing a predicate
> adjective clause) in English. So, now I'm wondering, is there any
> natlang precedent for a regular (either syntactic or morphological)
> distinction between restrictive and non-restrictive attributive
> adjectives? If not, is there a conlang precedent known to the List?

1. I haven't studied this question in detail, but my impression is that it
is somewhat misleading, though usual, to apply to adjectives the
restrictive--nonrestrictive distinction found in relative clauses. A NRRC
is predicated of the referent of the modificand -- "an X, which is Y"
attributes the property of being Y to the particular X referred to, whereas
nonrestrictive adjectives, such as "a calorific doughnut", "a noxious gust
of exhaust fumes", attribute to the class of things expressed by the noun
the property expressed by the adjective.

2. I recall having seen examples from French or Italian of the prenominal
or postnominal position of the adjective being correlated with
restrictiveness (among other semantic properties), the prenominal position
being the 'nonrestrictive' one and the postnominal the restrictive one, but
my knowledge of either language is not good enough to offer examples. (I
don't mean "un vecchio amico" vs "un amico vecchio", which is a different
distinction.) I mention this only as a prompt to others with better