Observations seem to show that the hampering of the infant’s movements is the factor which apart from all training brings out the movements characterized as rage. If the face or head is held, crying results, quickly followed by screaming. The body stiffens and fairly well coördinated slashing or striking movements of the hands and arms result; the feet and legs are drawn up and down; the breath is held until the child’s face is flushed. In older children the slashing movements of the arms and legs are better coördinated and appear as kicking, slapping, biting, pushing, etc. These reactions continue until the irritating situation is removed, and sometimes do not cease then. Almost any child from birth can be thrown into a rage if its arms are held tightly to its sides.... Even the best-natured child shows rage if its nose is held for a few seconds.... The original stimuli for bringing out the earliest manifestations of joy or love seem to be as follows: gentle stroking and soft tickling of the infant’s body, patting, gentle rocking, turning upon the stomach across the attendant’s knee, etc. The response varies: if the infant is crying, crying ceases and a smile may appear; finally a laugh, and extension of the arms. In older children and in adults this emotion, due both to instinctive and habit factors, has an extremely wide range of expression.[1] We understand of course that these expressions of emotion mean a preparation for action which will be useful in preserving life (anger), avoiding death (fear), and in reproducing the species (love), but even if our knowledge of the nervous system of man were complete we could not read out of it all the concrete varieties of human experience. The variety of expressions of behavior is as great as the variety of situations arising in the external world, while the nervous system represents only a general mechanism for action. We can however approach the problem of behavior through the study of the forces which impel to action, namely, the wishes, and we shall see that these correspond in general with the nervous mechanism. The human wishes have a great variety of concrete forms but are capable of the following general classification: 1. The desire for new experience. 2. The desire for security. 3. The desire for response. 4. The desire for recognition.