4. Ego Development and Adaptation

To Assume that all reactions to the external world are processes of adaptation would increase the vagueness of this concept; nevertheless, an attempt should be made to restudy the evolution of the ego in terms of adaptation. We do attribute a sort of ego to animals also (Freud, 1915b, p. 121). The animal is in contact with the external world by means of its receptors and effectors, it develops a “world of percepts” (“Merkwelt”), a “world of action” (“Wirkwelt”), and by “exerting regulative functions” it also creates an “internal world” (Uexküll, 1920). But we cannot speak, in regard to the animal, of that kind of separation into ego and id which exists in the human adult. The very fact that the concept of instincts as it pertains to the lower animals is much more comprehensive than the concept of instinctual drives as it pertains to man prevents such a separation. It is possible, and even probable, that it is just this sharper differentiation of the ego and the id—the more precise division of labor between them—in human adults which on the one hand makes for a superior, more flexible, relation to the external world, and on the other increases the alienation of the id from reality.1