Piaget's Four Stages of Cognitive Development

1. 2. Preoperational Stage - age 2 to age 7 - Children begin to talk, and they also begin to understand and manipulate in symbols and engage in symbolic play. They also begin to form a theory of mind - the ability to read other’s intentions, perceptions, thoughts, and feelings - during this stage. Also in this stage, children experience egocentrism - difficulty in taking another’s point of view.

2. 3. Concrete Operational - age 7 to age 11 - Children are better able to understand mental operations and are able to think logically about concrete events, but lack the ability to understand hypothetical/abstract concepts. During this stage, the children begin to understand the concept of conservation - the idea that quantity remains the same despite changes of shape.

3. 4. Formal Operational - age 11 to adulthood - Adolescents finally possess the ability to understand abstract concepts, and their skills of deductive reasoning, systematic planning, and logical thought emerge during this stage.

4. 1. Sensory Motor - birth to 2 years - Infants are preoccupied with learning how their body interacts and relates to the environment around them. The infants have well-developed sensory abilities. Infants also develop object permanence during this stage - awareness that objects exist even when not seen.