We examine two competing effects of beliefs on conditional inferences. The suppression effect occurs for conditionals, for example, “if she watered the plants they bloomed,” when beliefs about additional background conditions, for example, “if the sun shone they bloomed” decrease the frequency of inferences such as modus tollens (from “the plants did not bloom” to “therefore she did not water them”). In contrast, the counterfactual elevation effect occurs for counterfactual conditionals, for example, “if she had watered the plants they would (...) have bloomed,” when beliefs about the known or presupposed facts, “she did not water the plants and they did not bloom” increase the frequency of inferences such as modus tollens. We report six experiments that show that beliefs about additional conditions take precedence over beliefs about presupposed facts for counterfactuals. The modus tollens inference is suppressed for counterfactuals that contain additional conditions (Experiments 1a and 1b). The denial of the antecedent inference (from “she did not water the plants” to “therefore they did not bloom”) is suppressed for counterfactuals that contain alternatives (Experiments 2a and 2b). We report a new “switched‐suppression” effect for conditionals with negated components, for example, “if she had not watered the plants they would not have bloomed”: modus tollens is suppressed by alternatives and denial of the antecedent by additional conditions, rather than vice versa (Experiments 3a and 3b). We discuss the implications of the results for alternative theories of conditional reasoning. (shrink)

Pragmatic deficits of persons with autism spectrum disorders [ASDs] are often traced back to a dysfunction in Theory of Mind. However, the exact nature of the link between pragmatics and mindreading in autism is unclear. Pragmatic deficits in ASDs are not homogenous: in particular, while inter-subjective dimensions are affected, some other pragmatic capacities seem to be relatively preserved. Moreover, failure on classical false-belief tasks stems from executive problems that go beyond belief attribution; false-belief tasks require taking an alternative perspective on (...) the reality. While this capacity is functional in typically developing young children, it is impaired in ASDs. Typically developing children are capable of taking their interlocutor's perspective into account when communicating, whereas poor cognitive flexibility makes it difficult for persons with ASDs to grasp the inter-subjective character of communicative stimuli. This analysis predicts that those pragmatic processes that amount to merely taking into account salient contextual facts during utterance interpretation, without necessarily adopting the interlocutor's perspective, may be preserved in ASDs. (shrink)

ADHD is a psychiatric disorder characterised by persistent and developmentally inappropriate levels of inattention, impulsivity and hyperactivity. It is known that children with ADHD tend to produce incoherent discourses, e.g. by narrating events out of sequence. Here the aetiology of ADHD becomes of interest. One prominent theory is that ADHD is an executive function disorder, showing deficiencies of planning. Given the close link between planning, verb tense and discourse coherence postulated in van Lambalgen and Hamm (The proper treatment of events, (...) 2004), we predicted specific deviations in the verb tenses produced by children with ADHD. Here we report on an experiment corroborating these predictions. (shrink)