The movements of his limbs in active exploration, accompanied by sight, enables him to build up his knowledge of the world about him.

Learning this he soon falls to "experimenting" with the things of space.

Thus he begins to find out how things fit together, and what their uses are.
On the side of his movements we find him going through a series of remarkable adaptations to his environment.

At the beginning his movements are largely random discharges, or reflexes of an instinctive character, such as sucking.

Yet in the first month he shows the beginning of adaptation to the suggestions of his daily life, the first manifestations of acquired Habit.