A comparative developmental study of object sorting

The purpose of this study was to investigate the orthogenetic theory of Heinz V7erner as it applies to the development of categorizing behavior of average and slow learning children, and average and schizophrenic adults. Werner (1948, 1957) postulated that in whatever context development occurs, it begins from an initial stage of globality, proceeds through a stage of differentiation, and culminates in a final stage of hierarchic integration of the differentiated parts. Werner held that his orthogenetic principle not only applied to normal development, but also to the mental development of the schizophrenic and the mental retardate. He postulated that the mentally retarded individual follows the same developmental sequence as does the average individual but at a slower rate and that he evidences earlier developmental arrest. In the thought processes of the schizophrenic, Werner discerned evidence of developmental regression. Werner's theoretical formulations concerning the comparative development of the categorizing behavior of mentally average, mentally below average, and schizophrenic individuals have not been empirically investigated.