It had its foundations in the work of PERSON@1 , Gestalt psychology of PERSON@2 , PERSON@3 , and PERSON@4 , and in the work of PERSON@5 , who provided a theory of stages/phases that describe children 's cognitive development .

Cognitive psychology had its beginnings in the Gestalt psychology of PERSON@2 , PERSON@3 , and PERSON@4 , and in the work of PERSON@5 , who came up with a theory of `` stages '' or `` phases '' that describe children 's cognitive development .
