The subset property

Only DPs with postnominal adjectives can be used in response to the question  What kind of an N is X?” For example, if somebody were to ask What kind of lawyers are Rodrigo and Pedro? a possible answer would be Rodrigo y Pedro son abogados competentes ‘Rodrigo and Pedro are competent lawyers’ but not ??Rodrigo y Pedro son competentes abogados.

Another context in which we can test the subset property is provided by what we may call set-making verbs like distinguir ‘distinguish,’ diferenciar ‘differentiate,’ dividir ‘divide,’ or agrupar ‘group.’ When we say Distingo entre sueños posibles e imposibles ‘I can distinguish between possible and impossible dreams’ we mean that dreams can be classified as possible and impossible, and we suppose that a distinction can be made between dreams that are candidates to become materialized and those that are simply out of reach. ∗Distingo entre posibles e imposibles sueños sounds awkward if not ungrammatical because the subset reading is not possible. The following is another example in the same line (note that the strangeness in (1b) goes away if luminosas mañanas and tormentosas mañanas is interpreted as “echoed discourse”).

In sum, the subset property shows in those cases when adjectives are used restrictively because they serve to denote a class: a subset of the set mentioned by the N head. Prenominal adjectives usually are not qualified to trigger this interpretation.