C. G. Jung, The Theory of Psychoanalysis
“ We must now fit the new conception of libido into that theory of sexuality in childhood which is of such great importance in the theory of neurosis. Generally speaking, we first find the libido as the energy of vital activities acting in the zone of the function of nutrition. Through the rhythmical movements in the act of sucking, nourishment is taken with all signs of satisfaction. As the individual grows and his organs develop, the libido creates new ways of desire, new activities and satisfactions. ”
