A Decision Making Account for the Cognitive Processing of Demorgan′S Laws

The aim of this contribution is to propose a preliminary account for the intuitive recognition of the logical equivalences attributed to Augustus DeMorgan. Such equivalences concerned with the negation of conjunctions and disjunctions have been previoulsy studied only in the context of syllogistic tasks, but not from the perspective of decision making. An on-line exploratory study was conducted to test two hypotheses. The first hypothesis states that DeMorgan′s law for the negation of conjunctions is easier to recognize than the corresponding law for the disjunctions case. The second hypothesis states that spontaneous errors in the recognition of DeMorgan′s laws follow a cognitive pattern. The results obtained for the first hypothesis suggest that the disjunctions case is more intuitive than the conjunctions case. An heuristic explanation for such unexpected result is suggested. The second hypothesis testing results suggest that the observed errors are not random. Suggestions for future research are proposed.