Piaget’s Theory of Child Psychological Development
There currently exists a great deal of literature based on child developmental psychology from a variety of great psychologists, notably Freud, Erikson, Bowlby, Bandura, Vygotsky, and many others. However, this paper will focus on the theories of Jean Piaget.

Jean Piaget, a Swiss developmental psychologist and philosopher, was born in Neuchatel, Switzerland on August 9, 1896. After working with Alfred Binet in his children’s intelligence tests, Piaget developed an interest in the development of children He is widely known for his epistemological studies regarding children and formulating the Cognitive Theory of Development. Piaget self-identifies as a genetic epistemologist; “What the genetic epistemology proposes is discovering the roots of the different varieties of knowledge, since its elementary forms, following to the next levels, including also the scientific knowledge”. Jean Piaget was the first to believe that children were no less smarter than adults, they just think differently. Piaget refers to children as “little scientists” because they actively try to explore and make sense of the world around them
The model Piaget designed was a model that sought to explain how humans made sense of the world around them through collecting and organizing information from experiences with people, applied to children specifically. The model itself has four main stages in children: the sensorimotor stage (birth to two years), the pre-operational period (two to seven years), the concrete operations stage (seven to 11 years), and the formal operations stage (11 to 15 years). These age categorizations are a general approximation, as each child develops differently, and at their own pace. This pace is partly due to innate intelligence, and partly due to four pre-defined factors: maturation of the nervous system, experience, social transmission of information or teaching, and equilibration.
Sensorimotor Stage This is the stage where the early movements of an infant are uncoordinated and they do everything with their hands. Piaget believed that an infant’s understanding is adapted through sensory information being matched by the infant’s motor experiences. Infants are discovering that their bodies and their awareness are separate from the environment. Through interacting with the world through touching, seeing, sucking feeling, and using the other senses, the infant realizes that the world still exists outside of their awareness. This is called object permanence, being old enough to know that an object continues to exist even when not in view. After the child grasps object permanence, the next thing the child learns is directed groping. Directed groping refers to the child performing “motor experiments in order to see what will happen”.
Pre-Operational Stage The pre-operational stage lasts from two to seven years. The child is more capable in dealing with the environment. Although the child’s grasp with the world is still not fully systemic and logical, they start to develop a grasp of language, thinking more logically. Children are able to see links between two seemingly unrelated situations. For example, one of Piaget’s children had figured out that since she hadn’t taken a nap, it was not yet afternoon. An important characteristic of children at this stage of development is ego-centrism; they are unable to see things from any perspective other than their own. To prove this, Piaget conducted a simple experiment where he used a model of three mountains and walked the child around it, giving the child a chance to see the whole thing. He then placed the child at one end, and placed a toy at the other end. Upon asking the child what the toy would see, children in the pre-operation stage thinks the toys were looking at their own view. Children in this stage of development also have a hard time understanding the concept of irreversibility; one famous experiment that Piaget conducted consisted of showing children 16 boxes, six of which are yellow and 10, red. When children are asked whether there are more red boxes or boxes, in their responses children in this stage fail to see that yellow boxes are also boxes. Similar to the concept of irreversibility is the inability to conserve. Piaget shows two similar glasses full of water to children. The children understand that they two glasses are identical, and therefore have the same amount of water. However, after pouring the water from one glass onto another taller or wider glass, the children do not perceive that mass stays the same, even though shape changes. At this stage children also begin to categorize;
Concrete Operational Stage
The concrete operational stage, taking place from seven to 11 years, is characterised by the onset of logic and reasoning. The period is when the cognitive development of the child becomes a drastic improvement from the previous stages. Using the previous test of water in two glasses, this is the stage where the child learns that the mass stays similar, even in another container. They understand the concept of reversibility. Children also learn the concept of seriation: ordering objects according to differences. At the concrete operational stage, children have “no difficulty with the seriation task. The 10 sticks are ordered accurately without trial and error”. They are shown to have grown capable of mentally calculating and sorting three characteristics at once.
Formal Operations Stage
The formal operations stage starts from age twelve and develops into adulthood. Children gain the mental ability similar to that of adults, and have the ability to think about abstract concepts. Skills such as logical, reason, and planning are developed. Piaget believed that deductive logic emerged in this stage; the ability to use a general principle to determine a specific outcome. Adolescents in this stage are more capable of reason and gain the ability to think and evaluate all possible factors when considering problems.
Jean Piaget’s research into developmental psychology and genetic epistemology had one common goal: to find out how knowledge grew. His answer is that the growth of knowledge is one based on construction, of many simpler logical concepts building up onto more complicated ones into adulthood. Piaget was the first to tell that children were different from adults and were innately curious learners. While he did receive criticism for underestimating the mental capabilities of children, there is no doubt Piaget’s work was a milestone in the field of child psychology and helped people understand the development of their children and gain the tools to be able to shape them into good and responsible adults.