Sri Aurobindo
Letters of Sri Aurobindo
Volume IV - Part 2
Ego is not so easy to get rid of. It remains not only in spite of work, but in spite of knowledge or bhakti. The disappearance of ego means complete mukti. But even the Yogi who feels 
his separate being swallowed up in cosmic consciousness or some kind of transcendental consciousness, yet when it comes to outward action and reaction finds the superficial ego still there. That is why the ascetic has a horror of action and says that without ego it can’t be done. It can, but fully only when even these outermost things are finally taken up by the higher Consciousness entirely.