The Classic Edition of Dolph Kohnstamm-s Jean Piaget, Children and the Class-Inclusion Problem, first published in 1967, includes a new introduction by the author, describing for readers the original context for his work, how the field has moved forward and the ongoing relevance of this volume.
This enduring text offers a critical study of a cornerstone of Piaget-s theory that a child''s ability to solve problems of class-inclusion marks the beginning of the period of concrete (logical) operations at about 7 or 8 years of age. Kohnstamm''s experiments show, however, that, with a teaching method that provokes children-s authentic logical thinking processes, most children of 5 can already learn to solve a variety of class-inclusion problems, up to a level where they can even invent similar but new problems themselves. These results question the basic assumption of Piaget''s theory that logical operations can only develop in firmly connec
