As soon as the child can focus, it finds pleasure in watching moving objects, especial1y things that wave in the wind. But the number of possible amusements is small, until the child has learned to grasp objects that it sees. Then, immediately, there is an enormous accession of pleasure. For some time, the exercise of grasping is enough to secure the happiness of many waking hours. Pleasure in a rattle also comes at this stage. Slightly earlier is the conquest of the toes and fingers. At first, the movement of the toes is purely reflex ; then the baby discovers that they can be moved at will. This gives all the pleasure of an imperialist conquering a foreign country.: the toes cease to be alien bodies and become incorporated in the ego.
Source: On Education, especially in early childhood, 1926, by Bertrand Russell
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