In linguistics, veridicality is a semantic or grammatical assertion of the truth of an utterance. For example, the statement "Paul saw a snake" asserts the truthfulness of the claim, while "Paul did see a snake" is an even stronger assertion. Negation is veridical, though of opposite polarity, sometimes called antiveridical: "Paul didn't see a snake" asserts that the statement "Paul saw a snake" is false. In English, non-indicative moods are frequently used in a nonveridical sense: "Paul may have seen a snake" and "Paul would have seen a snake" do not assert that Paul actually saw a snake, though "Paul would indeed have seen a snake" is veridical, and some languages have separate veridical conditional moods for such cases. Nonveridicality has been proposed to be behind the licensing of polarity items such as the English words any and ever, as an alternative to the influential downward entailment theory proposed by Ladusaw. Anastasia Giannakidou argues that various polarity phenomena observed in language are manifestations of the dependency of polarity items to the veridicality of the context of appearance. The veridical dependency may be positive, or negative, and arises from the sensitivity semantics of polarity items. Across languages, different polarity items may show sensitivity to veridicality, anti-veridicality, or non-veridicality.
All downward entailing contexts are nonveridical. Because of this, theories based on nonveridicality can be seen as extending those based on downward entailment, allowing more cases of polarity items licensing to be explained. Downward entailment predicts that polarity items will be licensed in the scope of negation, downward entailing quantifiers like few N, at most n N, no N, and the restriction of every:
Non-monotone quantifiers
like exactly three students, nobody but John, and almost nobody are non-monotone but nevertheless admit any:
''Hardly'' and ''barely''
Hardly and barelyallow for any despite not being downward entailing.
Questions
Polarity items are quite frequent in questions, although questions are not monotone. Although questions biased towards the negative answer, such as "Do you give a damn about any books?", can sometimes be seen as downward entailing, this approach cannot account for the general case, such as the above example where the context is perfectly neutral. Neither can it explain why negative questions, which naturally tend to be biased, don't license negative polarity items. In semantics which treats a question as the set of its true answers, the denotation of a polar question contains two possible answers: Because disjunctionp ∨ q entails neither p nor q, the context is nonveridical, which explains the admittance of any.
Future
Polarity items appear in future sentences. According to the formal definition of veridicality for temporal operators, future is nonveridical: that "John will buy a bottle of Merlot" is true now does not entail that "John buys a bottle of Merlot" is true at any instant up to and including now. On the other hand, past is veridical: that "John bought a bottle of Merlot" is true now entails that there is an instant preceding now at which "John buys a bottle of Merlot" is true.
Habitual aspect
Likewise, nonveridicality of the habitual aspect licenses polarity items. The habitual aspect is nonveridical because e.g., that "He is usually cheerful" is true over some interval of time does not entail that "He is cheerful" is true over every subinterval of that. This is in contrast to e.g., the progressive aspect, which is veridical and prohibitsnegative polarity items.
s create generally good environments for polarity items: Such contexts are nonveridical despite being non-monotone and sometimes even upward entailing.
