 Śaṅkara’s philosophical conclusion is that non-reducible existence is numerically identical to pure non-intentional consciousness. Consciousness is nondual. It is the intrinsic nature of brahman itself. Consciousness is not simply the witness of one’s experience. It is the ultimate ground comprising an individual’s self-existence, the single self (ātman) of all sentient beings from a blade of grass to īśvara, and the metaphysical foundation of the entire universe.