The human mind utilizes the senses to acquire information about the external world. It then tries to comprehend the data it has acquired into meaningful patterns on which it can act. It builds from fragments to try to understand the whole. It does not have, as a native capacity, the knowledge of the whole, the oneness, the unity; this capacity, called Vijnana in the Upanishads, is reserved in its fullness for the supramental consciousness which starts from oneness and uses the data of the senses, but only within the context of its wider knowledge. The questions then arise as to whether the mind can gain data without use of the physical senses, and then, whether the supermind has capacities of knowledge of the specific manifested details and power to control them without necessarily relying on the senses (Ajnana).
Sri Aurobindo notes: “If we suppose a supreme consciousness, master of the world, which really conducts behind the veil all the operations the mental gods attribute to themselves, it will be obvious that that consciousness will be the entire Knower and Lord. The basis of its action or government of the world will be the perfect, original and all-possessing Vijnana and Ajnana. It will comprehend all things in its energy of conscious knowledge, control all things in its energy of conscious power. These energies will be the spontaneous inherent action of its conscious being creative and possessive of the forms of the universe.”
“The Upanishads declare that the Mind in us is infinite; it knows not only what has been seen but what has not been seen, not only what has been heard but what has not been heard, not only what has been discriminated by the thought but what has not been discriminated by the thought.”
Sri Aurobindo, The Upanishads, Kena Upanishad and analysis, pg. 102, 142-155