Piaget's Stages of Development

The first stage is called the Sensorimotor stage. It occupies the first two years of a child's life, from birth to 2 years old. It is called the Sensorimotor stage because in it children are occupied with sensing things and moving them. From these activities they learn what makes things happen, what the connections are between actions and their consequences. They learn to grasp and hold and what happens when they let go.

This happens later on in the stage. When they are new-born they have no concept of there being anything else apart from themselves in the world. In fact they think that they are the world. Piaget called this Egocentism; he said that children with this attitude were totally Egocentric. This does not mean that they are just plain selfish; it means that they do not even know that we or anything else exist apart from themselves. Children develop the idea of a world separate from and independent of themselves through their actions; it is only necessary for them to bump into a couple of things for them to be made painfully aware that, at least, something strange is going on, and table legs are not got out of the way just by closing your eyes. Like most things in life, acquisition of the concept of the external world is not as simple as that, but this is no place in which to enquire after such questions. It is easier to ask what evidence there may be that an individual has acquired the concept.

One piece of evidence is the child's apparent belief that objects exist when not perceived. This is called belief in Object Permanence. If a cloth is placed over a toy for which an eight-month old child is reaching, the child will immediately lose interest in the toy, as if the toy had ceased to exist. This is just what it has done for the child; as soon as anything passes from its experience that thing is no more. However, only a couple of months later, the same child in a similar situation will actively search for an object that has been hidden from its view. The older child has the concept of Object Permanence; it believes that there is an object under the cloth even though it cannot see it, feel it, hear it, taste it or smell it, and will make an effort to reach it if it so desires.

The child's problems are not over yet, though. It is not very agile in its thought; if a toy has been hidden very often in one place, and is hidden again but in a different place, with the child watching, the child will reproduce

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