When we recognize that the consciousness levels of Sat-Chit-Ananda are intrinsically a “truth-consciousness” and the supermind is the executive power of the Truth-Consciousness, we have to ask, how did the manifestation of Mind, Life and Matter become one of Ignorance?
Sri Aurobindo attributes this to the power of the overmind to work out each possibility in detail, and then to have them carry out their characteristic actions with an “exclusive concentration” that is so pervasive that it loses immediate awareness of the Oneness of which it is a part.
Sri Aurobindo explains that there is a separation, a filtering lens, if you will, between the supramental gradation of consciousness and the overmental gradation. This filter is transparent, so that the overmental gradation retains its innate awareness of the Oneness. There is a similar filtering lens between the overmental and the mental level, but in this case, it is more opaque, which permits therefore the quasi-independent action of each possibility of manifestation and the exclusive concentration which allows it to become Ignorant of its source and purpose.
Sri Aurobindo describes the result: “each mental being, each basic mental idea, power, force stands similarly on its separate self; if it communicates with or combines or contacts others, it is not with the catholic universality of the overmind movement, on a basis of underlying oneness, but as independent units joining to form a separate constructed whole. It is by this movement that we pass from the cosmic Truth into the cosmic Ignorance.”
From this point forward, the successively denser manifestations of mind, vital principal and matter all partake of this character of separation, division, fragmentation and ignorance.
reference: Sri Aurobindo, The Life Divine, Chapter 28, Supermind, Mind and the Overmind Maya