One student of this man explored the creative proc
One student of this man explored the creative process in an essay entitled "The Having of Wonderful Ideas. "That student, Eleanor Duckworth, later wrote the introduction to one collection of his essays. Also the teacher of Barbara Inhelder, in his later work, this psychologist considered cognitive structures of development as a differentiation of biological regulations, which played a role in a later concept. This psychologist described a phenomenon in which children are unable to comprehend that something that they cannot see is no longer there, known as object permanence. A proponent of innate instinctual schemas, this psychologist later developed four developmental stages, the last of which is the formal operational one. For 10 points, name this French psychologist. 
One student of this man explored the creative process in an essay entitled "The Having of Wonderful Ideas. "
Jean Piaget