Piaget, Jean (1896–1980)

Swiss psychologist whose studies of the development of thought processes in children have been influential in early-childhood research and on school curricula and teaching methods.

The subjects of Piaget's studies of intellectual development were his own children. He postulated four main stages in the development of mental processes: sensorimeter (birth to the age of two), preoperational (two to seven), concrete operational (seven to twelve), and formal operational, characterized by the development of logical thought.

Piaget believed this was a vital framework for studying human intelligence and he stressed the interaction of biological and environmental factors.

Piaget was born in Neuchâtel. He was a child prodigy in zoology, and by the age of 15 had gained an international reputation for his work on molluscs. Subsequently he studied at Neuchâtel, Zürich, and Paris, where he researched into the reasons why children fail intelligence tests. This gained him the directorship of the Institut J J Rousseau in Geneva 1921. During his subsequent career Piaget held many academic positions, some of them concurrent. In 1955 he founded the International Centre of Genetic Epistemology at Geneva University. He also held several positions with UNESCO at various times.

Piaget's works include La Naissance de l'intelligence chez l'enfant/The Origins of Intelligence in the Child 1936 and The Child's Construction of Reality 1936.