Because it is implicitly involved in material Nature, the supramental consciousness creates a harmony in the sphere of material energy. If we look closely and deeply at the operation of the world of matter, we see a marvelous and completely ordered mechanism that creates atoms, molecules, material substance, and eventually worlds, suns & stars, galaxies and universes. All of these have their own law of action and manifestation that can be seen to function in an order far beyond that which the human mind is capable either of creating or fully understanding.
As the evolution proceeds into the realm of life-energy, and then into the realm of mental-energy, we see the emergence of other principles, the principle of desire and repulsion, the principle of mental organisation and the contrasting dualities with which our mind is always engaged, and this can look like a confused middle ground that has left the security and organisation found in the purely material creation. Eventually however, the evolution continues to a new level of consciousness that has the harmony and order of Knowledge rather than the mechanistic order of Ignorance found in the material manifestation.
“…it emerges into a greater spontaneous harmony and automatic self-fulfilling action founded on the spiritual Truth of things. In this higher state the consciousness will see that Truth and follow the line of its energies with a full knowledge, with a strong participation and instrumental mastery, a complete delight in action and existence. There will be a luminous and enjoyed perfection of unity with all instead of a blind and suffered subjection of the individual to the universal, and at every moment the action of the universal in the individual and the individual in the universal will be enlightened and governed by the rule of the transcendent Supernature.”
Sri Aurobindo, The Life Divine, Book 2, Part 2, Chapter 26, “The Ascent Towards Supermind”