One of the most salient and inspirational figures in psychological and educational research of the 20th century, Piaget was also prolific, authoring or editing over 80 books and numerous papers. This volume is the fourth in a set of nine which reproduce his original texts.

Part 1 Conservation of Quantities and Invariance of Wholes; Chapter 1 Conservation of Continuous Quantities; Chapter 2 Conservation of Discontinuous Quantities and its Relation to One-One Correspondence1With the collaboration of M. Juan Jaen.; Part 2 Cardinal and Ordinal One-One Correspondence; Chapter 3 Provoked Correspondence and Equivalence of Corresponding Sets; Chapter 4 Spontaneous Correspondence Cardinal Value of Sets1With the collaboration of Mlle. Zoé Trampidis and Mme. Rafia Mehmed?emin.; Chapter 5 Seriation, Qualitative Similarity and Ordinal Correspondence; Chapter 6 Ordination and Cardination1In collaboration with Mlle Zahara Glikin.; Part 3 Additive and Multiplicative Compositions; Chapter 7 Additive Composition of Classes Relations between Class and Number; Chapter 8 Additive Composition of Numbers and Arithmetical Relations of Part to Whole1With the collaboration of Mme Tatiana-Katzaroff-Eynard and Mlle Zoé Trampidis.; Chapter 9 Co-Ordination of Relations of Equivalence and Multiplicative Composition of Numbers1With the collaboration of Mile Edith Vauthier.; Chapter 10 Additive and Multiplicative Composition of Relations and Equalization of Differences;