Originally published in 1974, this book presents a theory of cognitive development based on simple but powerful processes of inference. The author produces strong experimental evidence which not only challenged Piaget's ideas, but more importantly synthesized the old and new findings at the time into a newer theory of perceptual development.

Foreword and Acknowledgements. 1. Introduction 2. Relations 3. Inferences 4. Orientation 5. Position 6. Size 7. Number 8. Invariance 9. Vision and Touch 10. Experiments. References. Name Index. Subject Index.