Research conducted by Piaget indicates that as a child develops intellectually by adapting, either through inward assimilation or outward accommodation, to environmental experiences, he passes through a sequence of stages. Inhelder utilized Piaget's developmental theory of intelligence to measure observed reasoning in retardates and found that the first two stages observed in the development of reasoning in normals were also observed in retardates. However, no retardate achieved the third or formal level of reasoning. Consideration is given possible use of the theory and diagnostic methods to extend knowledge of the cognitive processes available to retarded individuals.
Will Beth Stephens (Fri,) studied this question.