Perception exists because of the ego: to keep it in check, to set it free. Alternate perceptions of other individuals control, sculpt, and mirror self-perception. Perception not only provides us with our reality, but it is also necessary for our survival as a species (a dual layer thing: we need reality to know we're alive, but we also survive by keeping our reality in check with alternate perceptions). Like a world-wide subconscious debate panel.
[ame="http://www.youtube.com/watch?v=yY5r_zox-a8"]YouTube - WHO IS THE MASTER? (ROBERT ANTON WILSON)[/ame]
I disagree slightly. The ego exists as a result of perception. The ego is merely our relativeness to the way we perceive everything around us.