Language for (im)possible worlds

Abstract The chapter focuses on thinking and talking about (im)possible worlds—eventualities which may or may not take place in the future—so moving to irrealis mood. It begins by considering the role of predicting and contemplating future possibilities in everyday life and in scientific study, then moves to the linguistic forms and the different grammatical resources that languages use for talking about future contingencies: lexical and syntactic constructions that indicate whether an utterance is factual, and so has a truth value, or whether it makes a modal judgment (expressing desire, doubt, hypothetical reasoning, etc.) and so can only be evaluated for its feasibility. We then review correlates of idea-generation and prediction in the brain and the neurological networks involved in factual, hypothetical, and counterfactual conditional statements. And we conclude by describing how, over time, children show increasing command of the linguistic forms that mark different types of unrealized possibilities—initially for instrumental purposes of expressing wishes and requests, moving to deontic, socially-prescribed modality (should, have to, can’t) and later-acquired epistemic modality expressing individual predictions and contingencies (may, likely, possible), shifting from use of future forms to hypothetical and counterfactual eventualities (if x happened, y would come about versus if x had happened, y would have come about). To conclude, we discuss how these age-related shifts reflect socio-cognitive development in the propositional attitudes that they express.