The Ego’s relation to the Id might be compared with that of a rider to his horse. The horse supplies the locomotive energy, while the rider has the privilege of deciding on the goal and of guiding the powerful animal’s movement. But only too often there arises between the Ego and the Id the not precisely ideal situation of the rider being obliged to guide the horse along the path by which it itself wants to go.
The poor Ego.. . serves three severe masters and does what it can to bring their claims and demands into harmony with one another. . . Its three tyrannical masters are the external world, the super-ego, and the Id.