(Non-)factive (non-)islands and meaning-based approaches

A key question in the literature on factive Weak Islands has been whether the effect is syntactic or semantic. Since Szabolcsi & Zwarts (1993), a key argument for the semantic nature of Weak Islands is the observation that the effect requires not just factivity, but also that the property described by the embedded clause is non-iterable with respect to the extracted argument (uniqueness). We present twocaveats concerning the notion of factivity needed in meaning-based approaches. First, we present novel data on factive non-islands showing that certain lexically factive verbs do not (always) lead to islandhood when combined with uniqueness. Second, recalling data from Cattell (1978), we argue that certain non-factive islands can be captured by the same meaning-based explanation. The emerging picture is that lexical factivity of the embedding verb is neither necessary nor sufficient to induce weak islands in combination with uniqueness; rather, what matters is whether or not there is a contextual entailment, pragmatic or lexical, that the complement proposition is true.