Jean Piaget, who lived from 1896-1980, was a self-proclaimed natural scientist. He spent his undergraduate and graduate studies in Switzerland working with mollusks. After his studies, Piaget began working with Theodore Simon in France developing standardized tests for children. Piaget began to see patterns in the answers given by the children and developed his theory of cognitive development.
History
Piaget began working for Theodore Simon in France standardizing tests for gauging reasoning abilities for children 5 to 8 years old. He became fascinated with the tests because he found that at certain ages, the children could answer a particular reasoning problem but at a younger age, the children would almost always answer the problem incorrectly. During the next 60 years, Piaget worked closely with children and developed the four stages of cognitive development.
Sensorimotor Stage
The sensorimotor stage is from birth to about 2 years and is defined through motor activity without the use of symbols. Knowledge of the world is gathered through physical interactions and experiences. It is in this stage that children can learn object permanence and early language.
An example of reasoning at this stage is object permanence. In the early months of life, if a toy is shown to a baby and then hidden under a blanket, the baby will forget about the toy. At about 9 months, if you hide a toy under a blanket, the baby with then go get the toy from under the blanket.
Preoperational Stage
The preoperational stage is from about the time a child learns to speak until about age 7. This stage of development is defined by increased use of symbols, language improves and memory is developed. This is also the stage when imagination is demonstrated. Also at this stage, a child can understand past and future.
Concrete Operational Stage
The concrete operational stage is from about age 6 or 7 until adolescence. In this stage, children begin to manipulate symbols in relation to concrete objects. Operational thinking develops during this stage as well as the relationship between cause and effect.
Formal Operational Stage
The formal operational stage is from adolescence to early adulthood. This stage when an individual can use deductive reasoning, abstract thinking and use comparison and classification.
