The Development of Conditional Reasoning: A Piagetian Reformulation of Mental Models Theory.

Empirical data concerning the development and use of conditional reasoning (if P then Q) indicate a variety of apparently conflicting results. Some studies report strong developmental differences in the ability to use conditional reasoning, whereas others make strong claims about the existence of reasoning abilities in young children. Further, conditional reasoning has been found to be highly variable even among adult subjects. Existing theories tend to concentrate on a single facet of these results. Proposed here is a theory of the development of conditional reasoning that combines specific procedures taken from the mental models theory of Johnson-Laird (1983) with a basically Piagetian analysis, specifically that of the development of possibility and necessity. An account of how this theory can potentially explain the various results concerning conditional reasoning is given and an extension to counterfactual reasoning is described