Conditionals on crutches: Expanding the modal horizon

Abstract

Using truth-value judgment tasks, we investigated the on-line processing of counterfactual conditionals such as If kangaroos had no tails, they would topple over. Face-value plausibility of the counterfactual as well as the complexity of the antecedent were manipulated. Results show that readers’ judgments deviate from face-value plausibility more often when the antecedent is complex, and when the counterfactual is plausible rather than implausible. We interpret our results based on the modal horizon assumption of von Fintel (2001) and argue that they are compatible with a variably strict semantics for counterfactuals (Lewis, 1973). We make use of computational modeling techniques to account for reaction times and truth-value judgments simultaneously, showing that implementing detailed process models deepens our understanding of the cognitive mechanisms triggered by linguistic stimuli.