Jean Piaget was a twentieth-century psychologist who is most famous for formulating a four-stage theory of childhood cognitive development that is still widely accepted today. Each stage is age-specific and marked by major hallmarks that indicate the development of specific thought-processing abilities. The first stage is sensorimotor, lasting from birth to 18-24 months, and is characterized by experience-based learning (Marcin, 2018). The hallmark is object permanence, the understanding that items and people exist even if they cannot be seen or heard. The second stage is pre-operational, lasting from the ages of two to seven, and characterized by the development of language, memory, and imagination (Marcin, 2018). The goal for the second stage is symbolic, representative thought. The third stage is concrete operational, lasting from the ages of seven to eleven, characterized by more logical and methodical manipulation of symbols. The child becomes more aware of the outside world and the major achievement is operational thinking, perceiving the relationship between objects (Marcin, 2018). The final and fourth stage is formal operational, lasting from adolescence to adulthood, and characterized by the developing ability to grasp abstract concepts and make hypotheses based on existing knowledge (Kail & Cavanaugh, 2016). The final milestone for this fourth stage is abstract thinking.
Jean Piaget first defined the concept of object permanence as the major hallmark of the sensorimotor stage of his cognitive development theory lasting from birth to approximately the age of two. It understands that items and people continue to exist even if they cannot be directly seen or heard. Children begin to search for objects if they are hidden instead of losing interest (Kail & Cavanaugh, 2016). This is an important precursor to other developmental milestones because it signifies that the child has a mental representation of the object and is not exclusively dependent on sensory perception.
Egocentrism, centration, and appearance as reality are markers of the second preoperational stage of Piaget’s theory of cognitive development. Firstly, egocentric intelligence signifies that children in that stage do not differentiate between their own perceptions and those of others (Kail & Cavanaugh, 2016). A classic example is a child covering up their eyes during hiding and seek because they believe if they cannot see anyone, then nobody can see them. Secondly, centration consists of fixating on one aspect and ignoring other relevant details (Kail & Cavanaugh, 2016). For example, a child might focus on the number of cookies one has without considering that they have variable sizes. Thirdly, appearance as reality is defined as the inability to distinguish between the two. If an actor portrays a superhero in a movie, the child will believe that the actor is in fact a superhero.
Piaget is recognized for his contributions to child development, but some elements of his theory have also been subject to criticism. Firstly, many of his theories are too vague to be scientifically tested. Secondly, recent research has demonstrated that Piaget underestimated infants’ understanding of object permanence and overestimated the sophistication of adolescents’ cognitive skills (Kail & Cavanaugh, 2016). Thirdly, he undervalued the importance of the sociocultural environment in cognitive development (Kail & Cavanaugh, 2016). Fourthly, Piaget’s four-stage model does not account for variability in performance. As a result, only some parts of Piaget’s theory are still accepted today, while others have been abandoned.
Kail, R. V. & Cavanaugh, J. C. (2016). Essentials of human development: A life-span view. Cengage Learning.
Marcin, A. (2018). What are Piaget’s stages of development and how are they used?. Healthline. Web.