Universal vs. particular reasoning: a study with neuroimaging techniques

The article investigates some general properties of universal vs. particular propositions occuring in syllogistic arguments, in order to explore the kind of interaction played by these two forms of reasoning inside cognition. The theoretical framework of our analysis is represented by recent developments of linear logic, focusing on the distinction between positive vs. negative status of logical operators (connectives and quantifiers). In the first part of the article, this distinction is introduced and applied to the analysis of the categorical propositions occurring in Aristotelian syllogism, the deductive paradigm particularly considered in psychological studies about human reasoning. In the second part of the article, an experimental research is presented in which the positive vs. negative alternation is studied in the transition from a universal (vs. a particular) categorical proposition to its contradictory, a particular (vs. a universal) categorical proposition; the experimental research is based on a reasoning task which shows that significant differences are exhibited by the two types of transitions.