While we may recognize the Oneness of Being, we nevertheless have a day-to-day experience of a limited action of consciousness that is centered in the ego-self. Sri Aurobindo indicates: “For we identify ourselves mentally, vitally, physically with this superficial ego-consciousness which is our first insistent self-experience; this does impose on us, not a fundamentally real, but a practical division with all the untoward consequences of that separateness from the Reality.”
The Ignorance that focuses us on the awareness and action of the ego-self is an exclusive concentration that keeps hidden and untapped the deeper knowledge based in the Oneness. As a corrollary, when we have some project in mind, we frequently find that we narrow our attention and focus all our knowledge and power of concentration on that specific project, putting all other issues, ideas, or situations aside. This type of “exclusive concentration” is one of the great powers of action and achievement in the world we live in, and it illustrates for us at a certain level what the ego-consciousness represents in relation to the larger Oneness. An exclusive concentration on the ego-self does not, however, destroy or obviate the reality of the larger Knowledge and Consciousness based in the One Omnipresent Reality, just as a focus for a particular time and project does not destroy or deny the larger awareness we may have at other times and in other circumstances.
Sri Aurobindo explains it thus: “This frontal power of Ignorance is a pwoer of concentration in a limited working, much like that power in our human mentality by which we absorb ourselves in a particular object and in a particular work and seem to use only so much knowledge, only such ideas as are necessary for it,–the rest, which are alien to it or would interfere with it, are put back for the moment: yet, in reality, all the time it is the indivisible consciousness which we are that has done the work to be done, seen the thing that has to be seen,–that and not any fragment of consciousness or any exclusive ignorance in us is the silent knower and worker: so is it too with this frontal power of concentration of the All-Consciousness within us.”
reference: Sri Aurobindo, The Life Divine, Book 2, Part I, Chapter 4, The Divine and the Undivine, pp. 402-403