Piaget theory - development of object permanence

Object permanence in Piaget's theory is the child's ability to realize if some object continues to exist even if it's not in his senses range.

According to Piaget, babies in the beginning of the Sensorimotor stage can't realize that some object still exist even if he isn't their visual or contact range.

Example

Benjamin is in the beginning of the sensorimotor stage. He knows his Mutant Ninja Turtles Dolls exist only when his brother Eric shows him them. But when Eric hides the dolls, Benjamin thinks they don't exist anymore.

At the Later stage the baby knows the object continues to exist even if they aren't in his sight:

When Eric hides the dolls from Benjamin, he knows they still exist, and he can still play with them even though he can't see them rihgt now.

At the end stage the baby understand that every action has a certain outcome. When Bejamin throws his Michael Angelo doll, Eric returns it to him, And Benjamin throws him back.

Benjamin understands his action result, the doll will fall somewhere every time Benjamin throws it.