Jean Piaget

Jean Piaget was a Swiss psychologist and epistemologist whose theory of cognitive development reshaped how educators and researchers understand how children come to know the world. He was born on August 9, 1896, in Neuchâtel, Switzerland, and died on September 16, 1980, in Geneva, Switzerland.

Piaget showed early scientific aptitude; he published his first paper, on an albino sparrow, at age ten and went on to study mollusks, earning a doctorate in zoology from the University of Neuchâtel in 1918 with a dissertation on the mollusks of Valais. He then turned to psychology, studying briefly at Zurich and at the Sorbonne in Paris, where he worked at the Alfred Binet laboratory standardizing intelligence tests on Parisian children.

Watching children give consistent wrong answers, he became interested less in their errors than in the reasoning behind them. From 1921 he worked at the Rousseau Institute in Geneva, later becoming its director, and developed his account of stages of cognitive development — sensorimotor, preoperational, concrete operational, and formal operational — through close observation of his own three children with Valentine Châtenay and of many others.

Across more than fifty books and hundreds of articles, including The Language and Thought of the Child, The Origins of Intelligence in Children, and The Construction of Reality in the Child, he framed knowledge as actively built by the learner through assimilation and accommodation. In 1955 he founded the International Center for Genetic Epistemology in Geneva, which he directed until his death.

The given name Jean is the French form of John, from the Hebrew Yochanan, meaning God is gracious; he carried it throughout his life.