The nature of Consciousness is a seminal theme at the heart of Upanishadic thought. Just as the Taittiriya Upanishad explores the fivefold sheath of human consciousness, the Koshas – Annamaya, Pranamaya, Manomaya, Vijnanamaya, and Anandamaya – the physical, vital, mental, intellectual, and causal layers of human individuality, and the Mandukya Upanishad lays out the four states of consciousness in terms of Jagrat, our waking, Svapna, dreaming, Sushupti, dreamless sleep state, and Turiya, pure consciousness; the Aitareya Upanishad outlines how Brahmn itself may be defined as Consciousness.
Reflecting deeply upon the nature of human and transcendental consciousness, the Aitareya Upanishad begins by stating that Atman is the only reality. Atma va idameka evagra – in the beginning was the Atman only, the Atman being defined as the first cause, the first principle, before creation itself, so to say. The Aitareya Upanishad then outlines how this ‘first principle’ created the universe in stages, beginning with the creation of space-time and crystallising its essence in the shape of a man finally.
Inner Cosmos
The Aitereya Upanishad draws attention to how the human body is the prime manifestation of Atman; perhaps also alluding to the fact that we need to understand our inner cosmic nature. ‘Who Am I?’ the classic question of the Upanishads, is first asked in the Aitereya Upanishad, urging the human to realise that he is more than the sensory organs, more than the mind, he is the Atman, actually. The Upanishad then touches upon the theme of how the Atman further sustains itself by procreation and nurturing of family, by metaphorically outlining how the Atman is born thrice in a human.
The first is when a child is conceived, through the shedding of the seed in the womb; second, when the child is born,and parents nurture the child to adulthood like themselves, and third, at the time of death, the human takes on another body, as determined by his Karma – his third birth. Through outlining the three births which the Soul takes, the Aitareya Upanishad elucidates that though this is the reality of the empirical world, we have to simultaneously understand that this created worldwide web of Samskara is only a projected one, not actually real. We need to understand the ‘first principle’behind the mystery of birth and rebirth, behind this endless cycle of Samskara and karma.
Multiple Selves
The Upanishad then wants you to reflect what the Atman is, and points out that Consciousness itself is the Atman. Absolute Consciousness itself has become the world of multiplicity. And even as it has become that, it has still actually not become those multiple selves.