Testing and extending a dual-source model of everyday conditional reasoning

• Applicant: Professor Dr. Karl Christoph Klauer
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2011 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 200771736

According to the dual source model of probabilistic conditional inference, human inferences draw on two sources of information: The syntactical form of given premises and content-specific background knowledge. We assume that the form-based component of the model is driven by a (resource-limited and fallible) monotonic system of reasoning, whereas the knowledge-based component is driven by summary assessments of chronically and momentarily salient beliefs, violating, across different contexts, coherence and monotonicity. The model is to be applied to three groups of classical problems: 1) Context effects, in particular suppression effects and effects of speaker expertise. Suppression effects are frequently seen as evidence for non-monotonic human reasoning and should thus map on the knowledge-based component of our model, whereas superficially similar effects of speaker expertise should map on the relative weight of form-based versus knowledgebased evidence. 2) The model is to be extended to other conjunctions than “if-then” to see whether the different syntactical forms are mapped on the form-based component in a manner consistent with the existence of a mental logic. 3) The relative role of cognitive resources for the knowledge-based and the form-based components of the model is to be assessed.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1516: New Frameworks of Rationality
• Participating Person: Professor Dr. Sieghard Beller