2018-12-112018-12-112003Suzanne Egan. “Counterfactual ‘only if’ conditionals”, 25th Annual Cognitive Science Conference, Boston, MA. Aug 2003. (Refereed).1069-7977http://hdl.handle.net/10395/2542Counterfactual ‘only if ’ conditionals.People understand a conditional, 'if A then B', such as 'if Peg went swimming then she felt well' by keeping in mind only true possibilities, e.g., A and B, not-A and not-B, not-A and B (Johnson-Laird & Byrne, 2002). Initially they think about only a few of them, e.g., A and B, because of working memory limitations. As a result, they make some inferences readily e.g., modus ponens (MP), given A, therefore B. But they find other inferences difficult, e.g., modus tollens (MT), given not-B, therefore not-A. The information does not correspond to their initial possibility and they must think about other true ones, e.g., not-A and not-B.enghttps://escholarship.org/uc/item/373511jhCounterfactualConditionalsOnlyIfConference report