Logic and Psychology: By Jean Piaget. Introduction by W. Mays. New York: Basic Books, Inc., 1957. 48 pp.

Based on three lectures delivered at the University of Manchester in 1952, this little book is a retroactive introduction to Piaget's work over the past twenty years in applying the methods of symbolic logic to the intellectual activities of the child and the adolescent.

Avoiding the fallacies of 'logicism'—which were so typical of the Würzburg school of Denkpsychologie and of the older philosophical psychology, wherein classical logic was employed as a causal explanation of psychological data in themselves—Piaget uses the algebra of logic to delineate specific psychological configurations and to put into the form of calculus those structures and operations which are central to thought processes. He thus reverses the procedures of Fitch, Hull, and others, who have been aspiring to a formalization of psychological theories by means of axiomatic logic.

Although this book manifests the eternally prefatory quality which (to this reviewer) is characteristic of Piaget's work, it constitutes nevertheless a tour de force and combines in brief compass a succinct introduction both to symbolic logic and to Piaget's psychological theories. The author makes the significant point that the logical calculus provides a nonlinear and nonatomistic technique for the study of thought in children and adolescents; that the developmental schemata of intelligence are thereby made available to qualitative analysis; and that symbolic logic is a necessary extension of the quantitative measurements which have long been accepted by psychologists.