Acharya Prashant explains that the ego is essentially a person's sense of self, which lacks any real foundation, support, or metaphysical grounding. He compares the ego's existence to a dream where everything appears real until one wakes up. Even though the ego is rootless, individuals continue to nourish it because they assume its foundation is solid, as evidenced by their actions, decisions, and the personal worlds they build. The ego makes itself feel indispensable by creating internal chaos and presenting unimportant matters as momentous, which distracts the individual from reality.