Jean Piaget

Jean Piaget (August 9, 1896 – September 16, 1980) was a Swiss psychologist and epistemologist known for his pioneering work in child development. His theory of cognitive development and epistemological view are together called "genetic epistemology." Piaget was interested in how children organize knowledge and how this organization changes as they grow. He began his career as a biologist, studying mollusks, but moved to psychology after developing an interest in psychoanalysis. He worked in Alfred Binet's laboratory, where he was tasked with standardizing a French version of an intelligence test. Through this work, he observed that young children gave qualitatively different types of answers to questions compared to older children, which led him to theorize that cognitive development was not simply a matter of adding more knowledge, but rather involved transformations in the way children understand the world. His theory is structured around the concept of developmental stages: the sensorimotor stage (birth to 2 years), the preoperational stage (2 to 7 years), the concrete operational stage (7 to 11 years), and the formal operational stage (from 11 years onward). These stages are defined by qualitative differences in thought processes. Piaget's method was based on careful observation of children and he often conducted conservation experiments to determine what children understood about concepts such as quantity, volume, and number. Piaget theorized that all children progress through these stages in the same order but at different rates. He believed that intellectual development was a process of adaptation (adjustment to the environment) through assimilation (incorporating new information into existing schemas) and accommodation (adjusting schemes in response to new information). Though subsequent research has questioned some aspects of his stage theory, especially the rigidity of stage transitions and ages, Piaget’s contributions to our understanding of childhood cognitive processes remain influential. His work has had a considerable impact not just on psychology, but also on educational practices, where his insights into child learning and development continue to inform instructional methods and curriculum design.