What Are the Piaget Stages of Development?

Jean Piaget was a psychologist and a genetic epistemologist. He was born in Switzerland in 1896 and wrote his first scientific paper at the ripe old age of eleven. His first scientific love was nature and zoology, but eventually, psychology captured his interest. He began to explore the intellectual development of children because he was fascinated by watching his daughter and nephew grow and learn. The cognitive theory that resulted from this fascination has become the world standard for explaining how children learn and mentally develop.

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Piaget proposed that intelligence is not something that a child just has. It is instead something that grows through a series of measurable stages. More importantly, perhaps, he put forth the assertion that young children are not less intelligent than older children or even adults, they just think differently. Piaget's theory includes four distinct stages of cognitive development, each of which will be described in detail in the following slides.

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The sensorimotor stage is the earliest stage of cognitive development. It begins when a child is born and lasts until he or she is around two years old. In this stage, everything the infant knows about the world is based on movement and sensation. Grasping, sucking, looking, and listening are their methods of processing input, and they realize that their actions can make things change in the world around them. They also learn about object permanence: the fact that things keep existing even when they can't see them anymore.

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The preoperational stage takes place from two to seven years of age. In this second stage of Piaget's theory, children expand on their understanding of language. They begin to think symbolically instead of just literally and begin to use pictures and words to identify and represent objects or ideas. They still tend to think in more concrete terms, however, so some symbolism and abstract ideas are difficult to grasp. In this stage, children are usually self-involved and can't yet see things from a perspective other than their own.

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The concrete operational stage is the third stage of cognitive development and takes place when a child is between seven and eleven years old. In this stage, children start to use logic to think about concrete events. They learn the meaning of conservation, meaning that they can recognize that the amount of liquid in a shorter, wider cup is the same amount as that in a taller, more slender glass. Thinking is still very concrete, but it is becoming more organized. This is also the stage in which children begin to use reasoning skills to predict outcomes of events before they happen.

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The formal operational stage begins at age twelve and continues on into adolescence. Finally, children are able to think more abstractly and use reasoning to think about hypothetical problems. Teenagers start to think less about just themselves and more about the moral, ethical, social, political, and philosophical issues in the world, which can only be understood with theoretical and abstract methods of thinking. They can now use deductive reasoning and have the ability to solve problems both hypothetical and concrete. This is also when children become able to plan for the future.

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As mentioned previously, Piaget was not asserting that the cognitive development of a child is a quantitative process. Children are not just amassing more knowledge as they move through life. Instead, they are changing the way that they think: it is a qualitative process. Intelligence is not simply based on how much input a child has absorbed or how much experience and knowledge a child has gained as they age. Cognitive development is based on a change in how one thinks and experiences the world.

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Before Piaget introduced his theory to the world, psychologists, scientists, and researchers believed that children were just smaller versions of their adult counterparts. They believed that children just simply weren't as smart as adults yet. They also tended to dismiss children as being "less than" in terms of cognitive development and intellectual capacity. Piaget, however, discovered that childhood is a very important time for learning and development and that children's brains are just as capable as those of adults. Once this was revealed, the field of psychology was changed forever.

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As big of an effect as Piaget's theory had on the world of psychology, this was not the only field affected by his hypotheses. Fields ranging from linguistics to education to sociology to science to evolutionary biology have all been affected by Piaget's discoveries. His theory completely changed the way that people thought about the human brain and how it worked. These progressive childhood stages came to represent so much more, and today many other scientists' theories are based on them.

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As with all important discoveries, Piaget's theory is not without its critics. Most criticisms come as a result of his research methods, which mostly consisted of observing his own children. The other children in his studies were also from high-class backgrounds, meaning that they may have had access to more resources than children of lower economic status. Although the children he studied may not have been representative of the larger child population as a whole, many researchers find it difficult to dispute some of his ideas.

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