The Weak Completion Semantics and Counterexamples

Abstract

An experiment has revealed that if the antecedent of a conditional sentence is denied, then most participants conclude that the negation of the consequent holds. However, a significant number of participants answered nothing fol lows if the antecedent of the conditional sentence was non-necessary, that is the case when given a conditional if A then C, both (¬A ¬C) and (¬A C) are deemed possible. The Weak Completion Semantics correctly models the answers of the majority, but cannot explain the number of nothing fol lows answers. In this paper we extend the Weak Completion Semantics by counterexamples. The extension allows it to explain the experimental findings.