Chapter 3 Understanding Human Development 73
individuals are similar. At each new stage, individuals incorporate new
experiences into what they know based on skills they have developed ear-
lier in previous stages. Chart 3-5 summarizes Piaget’s fi ndings.
By carefully documenting the thinking skills of many people at various
ages, Piaget improved the understanding of how cognitive skills develop
over time. Young children base their thinking on what they know through
their senses. Their experiences are limited. Therefore, when Shana, age
three, thinks that the moon is following her, it is a logical conclusion. This
type of thinking will change with her gaining further knowledge and
experience.
Although many researchers have added to the understanding of how
thinking occurs, Piaget’s four stages of cognitive development remain
important. His theory helps teachers understand how children learn and
develop and explains why they need continuous exposure to experimenta-
tion, discovery, and fi rst-hand experiences.
Vygotsky’s Sociocultural Theory
Many researchers have challenged Piaget’s theory, especially his belief
that humans learn primarily through experimentation with objects. They
point out the importance of human interaction as well as a person’s social
Piaget’s Stages of Cognitive Development
Age Stage Description
Infancy
(Birth to age 2)
Sensorimotor Babies begin to learn about the world
through their senses. At fi rst, learning
relies on refl exes but more purposeful
movement later enhances learning.
Toddler
(Ages 2 to 7)
Preoperational Toddlers and young children
communicate through language. They
recognize symbols and learn concepts.
Both hands-on experiences and
imaginative play are keys to learning.
Early childhood
(Ages 7 to 11)
Concrete operational Children in this stage learn to
think logically. They can make
generalizations, understand cause and
effect, group and classify items, and
suggest solutions to problems.
Adolescence
and adulthood
(Age 12 and up)
Formal operational Both logical and abstract thinking
are mastered during this stage. This
includes making predictions and
considering “what if” questions.
3-5
Piaget identified four
stages of cognitive
development.