Jean Piaget was a 20th century psychologist and theoretician best known for his creation of the developmental stages of children. 

Professional Life

Jean William Fritz Piaget was born in Neuchatal, Switzerland in 1896. He studied zoology at the University of Neuchatel and received his doctorate in 1918. Next, he studied psychology in Zurich briefly, and he spent two years at the Sorbonne in Paris studying the philosophy of science, logic, and abnormal psychology. While in Paris, Piaget worked with Theodore Simon and Alfred Binet, evaluating responses to an intelligence test Binet and Simon had developed for children. Piaget recognized that some of the errors were consistent among children of the same age, and he began to consider the possibility that younger children possessed different cognitive processes than older children or adults.

In 1921, he was hired as director of research for the Jean Jacques Rousseau Institute in Geneva. Eventually, he became co-director of the institute. Piaget became a professor of philosophy in 1925 at the University of Neuchatel, a professor of the history of scientific thought in 1929, and professor of experimental psychology in 1940 at the University of Geneva. From 1952–1963, Piaget taught child psychology at the Sorbonne. He also directed Geneva’s Centre International de l'Épistémologie Génétique from 1955–1980.

Piaget married Valentine Chatenay. The couple had three children, each of whom Piaget used in his experiments. He died in 1980. 

Contribution to Psychology

Piaget’s studies into the cognitive development of children led to several different theories. Piaget examined and evaluated the behaviors of his own children, observing their behaviors as infants, and watching and assessing the physical movements and actions they employed to accommodate their needs as they grew. Piaget also determined that younger children responded intuitively to a series of questions he created and that they developed more socially acceptable responses as they aged.

Piaget believed that children progress through specific phases of development during which they acquire predictable skills and behavior:

  1. Sensorimotor Stage: from age 0–2, a child interacts with his world through movement and explores his surroundings through the five senses.
  2. Preoperational Stage: from age 2–7 years, the child enters the fantasy stage, or magical thinking stage. It is during this time that children learn symbols in language, when egocentrism dominates, and motor skills are acquired.
  3. Concrete Operational Stage: from age 7–11 years, children learn to use logical thinking and perform concrete mental operations with the use of aids. Children begin to master abstract thinking, but will not be fully capable of abstract thought until the final stage. 
  4. Formal Operational Stage: in adolescence, around age 11 and beyond, a child is able to think abstractly, use reason to solve theoretical problems, and consider hypothetical scenarios. During this period, the child moves toward sociocentrism—a focus on the larger social world rather than focusing solely on the self.  

Piaget argued that children develop schemata, or ways of organizing knowledge, to help them understand the world. These schemata serve as framework through which information is organized. He identified three types of schemata:

  • Behavioral schemata are patterns of behavior that enable children to understand and respond to their experiences.
  • Operational schemata are frameworks imposed upon thought.
  • Symbolic schemata are mental symbols, such as letters, images, or verbal shortcuts. 

Piaget’s influences can be observed throughout the world in child psychology. The Jean Piaget Society supports his theories and is a world-wide organization that holds well-attended conferences each year. Piaget’s theories continue to impact education, psychology, evolution, philosophy, morality, and even artificial intelligence, as his theories were used in the development of many of our modern society’s computer operating systems and interfaces.


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