When every thought absorbs your attention completely, when you are so identified with the voice in your head and the emotions that accompany it that you lose yourself in every thought and every emotion, then you are totally identified with form and therefore in the grip of ego. Ego is a conglomeration of recurring thought forms and conditioned mental-emotional patterns that are invested with a sense of I, a sense of self.
In the well adjusted person the ego is the executive of the personality and is governed by the reality principle.
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