Priming effect in indicative and subjunctive exceptive conditionals

Abstract

We report the results of three experiments that examine the mental representations underlying the comprehension stages of negative exceptive conditionals using subjunctive mood (‘B a menos que A’, ‘B a no ser que A’; ‘B excepto que A’=‘B unless A’) and indicative mood (‘B excepto si A’ and ‘B salvo si A’=‘B except if A’). The mental representations during the comprehension stage were analyzed using a priming methodology. All experiments showed that participants read the true possibility ‘not-B & A’ faster when it was primed by exceptive conditionals requiring the subjunctive mood than when it was primed by exceptive conditionals requiring the indicative mood; other possibilities (‘B & A’, ‘B & not-A’, ‘not-B & not-A’) were primed equally by both connectives. The experiments showed that (a) when people understand negative exceptive conditionals using the subjunctive mood, such as ‘B a menos que A’/‘B a no ser que A’/‘B excepto que A’, they access the true possibilities ‘not-B & A’ and ‘B & not-A’, and (b) when they understand negative exceptive conditionals using the indicative mood, such as ‘B excepto si A’/‘B salvo si A’, they access ‘B & not-A’, but not ‘not-B & A’. We discuss the implications of this for current theories of reasoning.