Piaget, Jean

Piaget, Jean (1896–1980) A Swiss psychologist who made a major and distinct contribution to theories of human intellectual development, arguing that individuals actively make sense of the world, rather than merely being conditioned by it.

Piaget conducted a long series of experiments with children which led him to the conclusion that people pass through successive stages of cognitive development. He distinguishes four such phases, each characterized by its own distinctive logic, and each associated with the development of particular intellectual skills. In the sensorimotor stage (from birth to approximately 18 months), the child does not know that it exists as a separate object, and therefore cannot distinguish between its self, its actions, and the external objects upon which it acts. Its intelligence is expressed only in terms of sensory and physical contact with the environment. The pre-operational stage (from about age 2 to 7 years) is characterized by an increasing command of language, and an ability to think about concrete objects which are not actually present, but also by extreme egocentrism. At this stage of development children cannot take the role of others. They also lack understanding of abstract concepts such as causality, quantity, and weight. In the stage of so-called concrete-operations (which lasts from about the ages of 7 to 11 or 12), children start to classify objects, can take the role of others and understand the nature of cause and effect, but still have difficulty thinking about abstract concepts without referring these to real events or particular images with which they are familiar (hence ‘concrete’ operational stage). Finally, in the formal operations stage (12 years onwards), the young person is able to create his or her own classificatory systems and thus to achieve formal and abstract thought. Adolescents can apply general rules to particular problems, reason logically from premisses to conclusions, and think in terms of theories and concepts. Not all adults progress to this final stage however, since many people have great difficulty comprehending abstract concepts, and so do not move beyond the phase of concrete operations. Abstract thinking is dependent upon a social environment which exposes the individual to formal cognitive reasoning: the internal processes of the mind only develop through social interaction. Piaget argued that the various stages of cognitive development were the same cross-culturally; however, since the content of cultures varied, the particular beliefs that people learned in each of the stages would vary in time and place. If the surrounding culture teaches that cause and effect are related to magic then, clearly, this is how the individual will come to interpret the world.

Piaget's approach to intellectual development and the notion of developmental stages has been a major influence in cognitive psychology. Unlike most other psychologists, who have been concerned with behavioural aspects of cognition (such as short-term memory), Piaget has highlighted the epistemological questions surrounding the definition and categorization of knowledge. His theories of child intellectual development have also been incorporated by some teachers and educationalists into methods of teaching young children. Most of his extensive writings are now translated into English (see H. E. Gruber and and J. J. Voneche ( eds.) , The Essential Piaget—An Interpretive Reference and Guide, 1977
).