Priming effect on the exceptive conditional ‘except if’

Abstract

Here we report the results of one priming experiment that examines the comprehension of exceptive conditionals—for example, ‘Mary will go out tonight except if she has an exam tomorrow’—and indicative conditionals—for example, ‘Mary will not go out tonight if she has an exam tomorrow’. The experiment showed that participants read the true possibility ‘Mary is not going out tonight and she has an exam tomorrow’ faster when it was primed by an exceptive conditional than when it was primed by an indicative; other possibilities (‘Mary is going out tonight and she does not have an exam tomorrow’, ‘Mary is going out tonight and she has an exam tomorrow’ and ‘Mary is not going out tonight and she does not have an exam tomorrow’) were primed equally by both connectives. The experiments showed that (1) when people understand ‘B except if A’, they access the true possibilities ‘not-A & B’ and ‘A & not-B’, and (2) when they understand ‘B, if not-A’ they access ‘not-A & B’, but they do not access ‘A & not-B’. We discuss the implications of this for current theories of reasoning.

Keywords:

• Conditional
• Exceptive conditionals
• Mental model theory
• Reasoning
• Suppositional theory

We would like to thank García-Madruga and two anonymous reviewers for their thoughtful suggestion on a first version of this manuscript. We thank Alicia Bolaños’ helpful comments on an earlier draft.

We would like to thank García-Madruga and two anonymous reviewers for their thoughtful suggestion on a first version of this manuscript. We thank Alicia Bolaños’ helpful comments on an earlier draft.