Experimental investigations of licensing environments for NPIs in English

In an experimental investigation of NPIs and their licensing conditions in German, Richter & Radó (2013) showed that Weak Licensors can partially license Strong NPIs. In two experiments we investigate these results for English. In Experiment 1 we empirically identify 16 Strong and 16 Weak NPIs by examining their acceptability when licensed by sentential negation and weak adverb licensors and find results similar to German. In Experiment 2 we compare the licensing abilities of two different types of conditionals, normal, causal conditionals and rhetorical conditionals, such as `If you win, I’ll eat my hat’. We did not find statistically significant evidence for our prediction that rhetorical conditionals might be able to license strong NPIs better than normal conditionals, but we discuss possible changes in the experimental design that might lead to different results. Experiment 2 thus serves as a pilot study for future investigations.