What is the major accomplishment of the Sensorimotor stage (birth to 2 years) in Piaget's theory?

The major accomplishment of the Sensorimotor stage in Piaget's theory is the development of object permanence. This concept refers to the understanding that objects continue to exist even when they are not visible. During this stage, infants learn through their senses and actions, actively exploring their environment, which leads them to realize that things can exist independently of their immediate perception.

As infants engage with the world around them, they begin to search for objects that they can no longer see, indicating that they have formed a mental representation of these objects. This understanding typically develops around 8 to 12 months of age and is a significant cognitive leap, marking the transition from a reliance on immediate sensory experiences to a more complex understanding of the permanence of objects.

The other concepts, like egocentrism, reversibility, and conservation, emerge in later stages of cognitive development. Egocentrism is associated with the Preoperational stage, where children have difficulty seeing things from perspectives other than their own. Reversibility and conservation are concepts that develop later, typically in the Concrete Operational stage, where children understand that certain properties of objects remain constant despite changes in form or appearance.