Determined that males (N=70) demonstrate higher level of intellectual development than females (N=70), that males mature intellectually earlier than females, and that there appear to be factors other than age and sex that are related to development of formal operational reasoning. Implications of these and other results are discussed. (JN)

Discusses whether formal thought constitutes a structured whole and role of propositional logic in advanced reasoning. Presents aspects of advanced reasoning model, considering hypothesis generation/testing as central processes in intellectual development. Argues that advanced reasoning schemata are linked by these processes and should be…