ABSTRACT
The adaptation-equilibration model attests to the role of experience and, therefore, to the possibility of variations in performance due to the history of the subject's experiences and to the relative difficulty of the tasks. The concept of conservation has been the focus of research inspired by Piaget's theory into the mechanism of intellectual development. Theoretically, if the child saw the deformation as making the one ball lighter and the subtraction as making the other ball lighter, there should be a cognitive conflict which might well produce a resolution in the form of a conservation judgement. P. E. Vernon observed a close correspondence between the performance of English and West Indian schoolboys on tasks assessing conservation of surface, quantity and volume. Successful training has been reported for a training programme which included classification, compensation and reversibility training, for compensation and identity, for a reversibility and cognitive conflict procedure and for reversibility, identity and compensation.
