<P>Originally published in 1975, the study of logical reasoning was undergoing rapid expansion and this volume brings together the latest thinking in the area, in such a way that the relation between Piagetian and non-Piagetian traditions are examined, as well as the connection between the study of reasoning and the area of linguistic inquiry. It would have been required reading for all those interested in reasoning in children and adults at the time and can be read in its historial context today. </P>