Positive Polarity Items cannot appear in the scope of a clausemate negation
. This statement stands in need of a double qualification. For one thing, n
ot all negative environments are alike, and some PPIs can occur in one type
of negative environment but not the other. I argue that indefinite NPs wit
h a are PPIs of the weakest type, and therefore only incompatible with the
weakest of negative contexts, basically those instantiated by the negative
adverb not. Second, indefinites with a can be found to occur in the syntact
ic scope of not. This happens under either of two conditions: on the one ha
nd, not may signal metalinguistic negation, which differs substantially fro
m ordinary negation. On the other hand, the indefinite may (in a language l
ike English at least) take semantic scope over not. The latter strategy is
unavailable in a scrambling language like Dutch, where the indefinite can m
ove overtly to a syntactic position having scope over the negative adverb.