Ego feeds itself principally off three different kinds of impressions that come into the body.
Ego is a lower manifestation of Self, or
Purusha, that appears in the interaction of the first three
universal principles, materiality, desire, and power. It is a mechanical or reflexive response to the action of life, not a conscious one — the conscious response only emerges at the level of Being, which relates to the fourth universal principle. Within the first three universal principles, ego lives in a world of hunger — what the Buddhists call the world of hungry ghosts. And the three forces it finds itself surrounded with are what it feeds on.
The first being food for ego is material things. When this lower part of the Self encounters material existence, it takes it all as an affirmation of its own existence. This is a kind of food which feeds the ego with a concrete understanding of its own existence, which it takes as real. this is the equivalent of ordinary food which is chewed and digested by human beings. Ego takes the material and incorporates it into its being, constructing a concrete existence for itself.
The second being food for ego is desire. This is the equivalent of air in the being food of man — ego breathes desire in and out, wanting and not wanting. The interaction of wanting and not wanting with material creates the sensation of life. All ordinary cravings arise here from the ingestion of this food by the ego. In addition, the existence of the material, compounded by the ingestion of craving, creates a situation where the ego needs to defend itself and its material existence. It is, for all intents and purposes, defending its food source, a primal instinct for every animal.
In order to do this, the ego needs a third food, the highest food, power, which is the equivalent of impressions for a man. Power provides the force necessary to defend all three of the food sources. Ego enjoys feeding on power, because it confers authority on it.
Everything, in other words, that ego does arises out of hunger. Because of its automatic functioning, ego is insatiable; it doesn't see limits to how much material, desire, or power it ought to eat, and, in fact, the ego is almost always an obese creature. Because it isn't literally visible, this can, in its subtleties, be difficult to see, but the more exaggerated effects that overgrown egoists project around themselves can often be noticed.
The ego is furthermore a predator; it has no conscience to speak of, and will readily feed on anything in its immediate vicinity, if it can get hold of it. It will kill in order to feed, literally as well as metaphorically. Only to the extent that some level of conscience is actually present are any limits placed on its behavior.
At the same time, we cannot make the ego an enemy. We need it; and if we try to make it an enemy, it will surely defeat us. Al 'Arabi Warns of exactly this problem in the
Divine Governance of the Human Kingdom. Referring to it, almost lovingly, as the "evil – commanding ego," he reminds us that the ego is fully capable of inflicting great damage on our inner work, if we don't recruit it to our cause. He suggests we make friends with it through negotiation, rather than trying to destroy it. This is reminiscent of Gurdjieff's principle of conscious egoism — an egoism turned toward the service of inner growth, rather than poised in opposition to it.
We should keep an eye on what the ego is eating, and make sure that it gets the appropriate food — not everything it wants, but what is necessary.
May your soul be filled with light.