The overmind

… the overmind knows the One as the support, essence, fundamental power of all things, but in the dynamic play proper to it it lays emphasis on its divisional power of multiplicity and seeks to give each power or Aspect its full chance to manifest, relying on the underlying Oneness to prevent disharmony or conflict. Each Godhead, as it were, creates his own world, but without conflict with others; each Aspect, each Idea, each Force of things can be felt in its full separate energy or splendour and work out its values, but this does not create a disharmony, because the overmind has the sense of the Infinite and in the true (not spatial) Infinite many concording infinities are possible.

—Sri Aurobindo, Letters on Yoga, p. 248


In its nature and law the Overmind is a delegate of the Supermind Consciousness, its delegate to the Ignorance. Or we might speak of it as a protective double, a screen of dissimilar similarity through which Supermind can act indirectly on an Ignorance whose darkness could not bear or receive the direct impact of a supreme Light. Even, it is by the projection of this luminous Overmind corona that the diffusion of a diminished light in the Ignorance and the throwing of that contrary shadow which swallows up in itself all light, the Inconscience, became at all possible. For Supermind transmits to Overmind all its reali- ties, but leaves it to formulate them in a movement and according to an awareness of things which is still a vision of Truth and yet at the same time a first parent of the Ignorance.

—Sri Aurobindo, The Life Divine, p. 307