Counterfactuals and quantificational force Experimental evidence for selectional semantics

Theories of counterfactuals agree on the use of a comparative similarity relation, but disagree about the quantificational force of counterfactual modals. This study reports findings from two experiments designed to evaluate the predictions of three prominent approaches: universal theories, homogeneity theories, and single-world selection theories (supplemented with supervaluations over selection functions). To differentiate the predictions of these theories, we examined counterfactual sentences embedded under various quantifiers and elicited graded truth-value judgments from speakers. The results provide empirical support for selection-based theories, while posing challenges to universal and homogeneity approaches. Additionally, we argue that a more recent implicature-based theory also fails to align with our findings. We discuss the broader implications of these results, including the similarities and differences between counterfactuals and plural definites.