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Jean Piaget’s Theory of Cognitive Development

Jean Piaget’s theory of cognitive development suggests that children progress through a series of stages of mental development. The theory outlines four distinct stages from birth through adolescence, focusing on how children acquire knowledge, reasoning, language, morals, and memory.

Piaget’s stages of development are:

Sensorimotor Stage0-2Object permanence
Preoperational Stage2-7Egocentrism and symbolic thought
Concrete Operational Stage7-11Conservation and inductive logic
Formal Operational Stage11 and upAbstract thought and deductive logic

An Overview of Jean Piaget’s Theory

The theory was the work of Jean Piaget, a Swiss psychologist who became the first to conduct systematic research on children’s cognitive development. This theory had a tremendous impact on the fields of developmental psychology and education.

What made Piaget’s stages so unique and revolutionary?

  • Piaget was one of the first to suggest that the way children think is fundamentally different than that of adults. Prior to Piaget, the prevailing belief was that children were smaller versions of adults and that their thinking was simply less competent than that of adults. Piaget’s work demonstrated that children think about the world differently than adults do.
  • Piaget’s stages suggest that kids actively participate and construct their knowledge. Rather than believing that children passively take in what they observe, Piaget believed that kids play an active role in learning about the world around them.
  • Each of Piaget’s stages is marked by distinctive shifts in how kids think. His theory describes four stages of cognitive development that children go through as they learn more about the world.
  • During the earliest stages of development, children learn about the world primarily through their senses. As development progresses, children’s intellectual abilities become increasingly sophisticated, eventually allowing them to think and reason about abstract concepts and problems.

How Did Jean Piaget’s Theory Develop?

Piaget’s fascination with science began early in life, with his initial interests lying in the natural sciences. Born in the late 1800s, Piaget was a child prodigy. He published his first scientific paper on mollusks when he was just 11 years old. He went on to earn a Ph.D. in Zoology. After spending a semester studying with Carl Jung, Piaget developed a stronger interest in psychology.

It was through his work in Alfred Binet’s laboratory in Paris that Piaget developed an interest in children’s cognitive development. Charged with interpreting the results of the standardized intelligence tests that Binet had developed for the French government, Piaget was interested in why children answered questions incorrectly. Upon questioning kids about their answers, he realized that how they responded depended upon their level of intellectual development.

His observations of his young nephew and later his own children added to his growing theory of childhood cognitive development.

Piaget’s theory focused on three critical components:

  • Schemas, or the mental frameworks that make up knowledge
  • The ways that this knowledge is acquired or altered (assimilation, equilibration, and accommodation)
  • The stages of mental development that children go through as they obtain and create knowledge.

Piaget’s Stages of Cognitive Development

In Jean Piaget’s theory, he proposed that children progress through four distinct stages of intellectual development. Each stage is marked by changes in how kids think about and relate to the people and objects in their environment.

1. The Sensorimotor Stage (ages 0-2)

  • Children learn about the world via their senses
  • Basic activities such as sucking, rooting, listening, grasping objects, and sucking on things are how infants learn about the world
  • As they progress through this stage, they eventually learn object permanence, or that things continue to exist even when they can no longer be seen

During the first two years of life, a child’s knowledge of the world stems from motor actions and sensory information. A remarkable amount of learning takes place during this relatively brief period.

One of the critical events of the sensorimotor stage is the development of object permanence or the understanding that objects continue to exist even when they cannot be seen.

The physical milestones of this stage also contribute to cognitive development as children explore the world through reaching, grasping, rolling, crawling, and eventually walking. The earliest foundations of language development are established during this stage as well.

During the sensorimotor stage, infants learn about the world around them through their senses, perceptions, and motor skills. Infants are limited in terms of their ability to independently explore, so every interaction they have with people and the environment serves as an important learning opportunity.

Babies and toddler rely on the basic abilities they were born with, such as rooting, sucking, chewing, and looking, to learn more about themselves, the people around them, and the environment they live in.

Looking at a very young child, you might question just how much they really are able to generate knowledge from their actions. The truth is that babies can acquire a tremendous amount of information just by utilizing their sensory systems and motor skills. Sights, sounds, movements, tastes, smells, and textures provide valuable information that helps infants discover the world.

6 Sensorimotor Substages

Piaget believed that the events of this stage were so dramatic that he divided the sensorimotor stage further into six distinct substages.

1. Reflexive Activities (0 to 1 month): The infant gains knowledge of the world through their inborn reflexes at this substage. At this point, an infant’s actions involve performing reflexive actions such as sucking at a nipple or chewing on a toy.

Through these actions, new objects are assimilated, and reflexes are accommodated to respond to new objects. While these actions seem very basic, they serve as an important stepping stone in intellectual development.

2. Primary Circular Reactions (1 to 4 months): Infants begin to repeat reflexive actions that are related to their own bodies and that they find pleasurable. For example, a baby might suck her thumb or kick her legs against a soft blanket. Babies also begin to notice when objects disappear.

3. Secondary Circular Reactions (4 to 8 months): Babies continue to repeat actions that they find enjoyable, but they also begin to perform actions that involve manipulating objects. For example, a baby might shake a toy in order to hear the sound that it makes.

4. Coordination of Reactions (8 to 12 months): During this stage infant begin to perform more goal-directed actions. Rather than simply repeating pleasurable actions, they will intentionally seek out actions or objects in the environment that they want to play with. For example, a child might push aside unwanted object to get to an interesting toy.

5. Tertiary Circular Reactions (12 to 18 months): During this substage, infants begin to experiment with new ways of solving problems. Babies now display intentional reactions that they have learned during the earlier substages. For example, a child might take a stack of blocks apart and will now try to figure out how to put it back together again. Babies also explore trial-and-error processes in order to see what happens or what sort of reaction they will get.

6. Early Representational Thought (18 to 24 months): During this final sensorimotor stage, children begin to show signs of symbolic thought. Babies now possess mental representations of objects, which means they are also able to think about things that are not there.

Object Permanence During the Sensorimotor Stage

One of the hallmarks of the sensorimotor period in Piaget’s stages of development is the presence of egocentrism. Children at this stage of development cannot take other people’s perspective.

In addition to being unable to see things from other people’s perspectives, children at this stage also develop object permanence or the understanding that objects continue to exist even when they cannot be seen. During the early sub-stages of the sensorimotor stage, children lack any sense of object permanence. If an object cannot be seen, it simply no longer exists in their view.

As children progress through this stage, they begin to learn more about the objects around them and the fact that things can exist even though they may be hidden. During the first month of life, a baby may track an object with its eyes but ignore the objects sudden disappearance. From about 1 to 4 months, an infant will stare at the spot where an object vanished.

It is during the age from around 4 to 8 months that children start to search for an object that is partially concealed, and from 8 to 12 months a clear understanding of object concepts begins to emerge.

If you have ever played peek-a-boo with an infant, you can see the development of object permanence in action. A very young infant might not search for a hidden object and will be very surprised when it pops out from a hidden spot. On the other hand, a child with an emerging sense of object permanence will actively search for the hidden object.

The sensorimotor stage of development serves as an important building block for future cognitive growth. While children may be limited to learning through their senses and motor actions, this does not mean that this is an uneventful stage of development. A tremendous amount of growth takes place during the sensorimotor stage, laying the foundation for the upcoming preoperational stage of development.

 2. The Preoperational Stage (ages 2 to 7)

  • Egocentrism is a common characteristic of this stage, since children struggle to see things from other’s point of view
  • Children begin to think symbolically and are able to understand that symbols and words represent objects in the real world

The early part of this stage of cognitive development is marked by the emergence of language. Why is this an important part of Piaget’s stages? Because it suggests that children are capable of symbolic thought. Children utilize language to symbolically represent objects, people, and ideas.

While their thinking is becoming increasingly sophisticated, kids at this stage of cognitive development struggle with logic and mentally transforming information.

Piaget’s experiments demonstrated, for example, that kids in the preoperational stage have difficulty with conservation.  For example, kids are shown two glasses containing the same amount of liquid. The liquid is then poured into two different containers – a short, wide glass and a tall skinny glass. While they saw that the two amounts were equal, children in the preoperational stage will invariably select the tall skinny glass as containing more.

This period of cognitive development is also marked by an inability to take another person’s perspective, which Piaget called egocentrism.

In his experiments, Piaget found that when children were asked to select an image depicting another person’s view of a scene, they would simply select their own view because they could not imagine the scene from the other individual’s perspective.

 3. The Concrete Operational Stage (ages 7 to 11)

  • Children begin to utilize logical and organized in their thinking, but they tend to think about things in very concrete terms
  • They struggle to think about abstract ideas or concepts
  • They learn conservation, or the idea that the total amount of something such as a glass of water remains the same even if it is divided into smaller parts

The concrete operational stage of cognitive development is marked by the emergence of logical thought. Kids become much more capable at applying logic, but they also tend to be very concrete, literal thinkers. At this point, they still struggle with abstract ideas and hypothetical situations.

In addition to thinking more logically, kids also become less egocentric and capable of conservation. At this stage of cognitive development, children can better consider other people’s perspectives and understand that other people do not see things the same way they do.

 4. The Formal Operational Stage (age 11 to adulthood)

  • Children at this stage of cognitive development are beginning to utilize abstract thinking when they consider problems
  • As they consider complex problems about the world, including social and moral issues, they become better at considering theoretical and abstract ideas

The fourth and final stage in Piaget’s stages of cognitive development is characterized by the emergence of abstract thought. Instead of simply relying on their own experiences, kids begin to imagine multiple possible ways of solving problems.

Whereas younger kids typically rely on trial and error when solving problems, those who have reached the formal operational stage can systematically solve problems using logic. Trial-and-error may still come in to play, but it involves a more methodical and organized approach rather than the haphazard style that younger kids use.

In Jean Piaget’s theory, he did not identify exact ages when these stages occur. However, most explanations of the theory identify a typical range during which the stage often occurs.

While Piaget believed that these stages were universal, not all individuals reach the later stages. Not everyone, for example, reaches formal operations and becomes skilled at deductive reasoning and abstract thinking.

The Impact of Jean Piaget’s Theory

Jean Piaget’s theory of cognitive development had a lasting impact on the fields of psychology and education. Most educational programs today are based around the idea that instruction should be geared towards a child’s developmental level. Strategies such as peer-led instruction and social facilitation are also rooted in the tenets of Piaget’s stages.

While influential, Piaget’s theory has not been without criticism. Many note that development does not necessarily align to a series of distinct stages, a fact that even Piaget himself observed.

Others suggest that his stages may have been too broad, vague, and not clear on how children’s learning actually occurs.

Researchers also suggest that Piaget underestimated children’s abilities. For example, the understanding of object permanence is thought to occur much earlier than what Piaget believed.

Nevertheless, Piaget’s theory of cognitive development had a powerful impact on our understanding of the intellectual abilities and growth of children.


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