The 7th verse of the Mandukya Upanishad is the most important verse of that short work. There the word, advaita, shows up for the first time in history, and thus it is arguably the most important verse in advaita vedanta. It is the verse in which the fourth state, the stateless state, appears (after the previous appearances of the three states, in verses 3, 4, 5, respectively, of waking, dreaming, and deep sleep). Because of its importance, I am including various translations here for triangulation purposes.
They consider the Fourth to be that which is not conscious of the internal world, nor conscious of the external world, nor conscious of both the worlds, nor a mass of consciousness, nor conscious, nor unconscious; which is unseen, beyond empirical dealings, beyond the grasp (of the organs of action), uninferable, unthinkable, indescribable; whose valid proof consists in the single belief in the Self; in which all phenomena cease; and which is unchanging, auspicious, and non-dual. That is the Self, and That is to be known.
~Gambhirananda
(And this is from Sankara’s commentary as translated by Gambhirananda:
By the phrase, `nantah-prajnam, not conscious of the internal world’, is eliminated Taijasa. By `na bahis-prannam, not conscious of the outside world’, is eliminated Visva. By `na ubhayatah-praj’nam, not conscious of either’ is ruled out the intermediate state between dream and waking. By `na prajndnaghanam, not a mass of consciousness’ is denied the state of deep sleep, for this consists in a state of latency where everything becomes indistinguishable. By ‘na prajnam, nor conscious’ is denied being aware of all objects simultaneously (by a single act of consciousness). By ‘na aprajham, nor unconscious’ is negated insentience.
Hence, It is adrstam, unseen. Since It is unseen (i.e. unperceived), therefore It is avyavahdryam, beyond empirical dealings; agrdhyam, beyond the grasp, of the organs of action; alaksanam, without any logical ground of inference, that is to say, uninferable. Therefore It is acintyam, unthinkable. Hence It is avyapade-syam, indescribable, by words. It is eka-dtma pratyaya- sdram, to be spotted by the unchanging belief that It is the same Self that subsists in the states of waking and so on. Or, the Turiya that has for Its sara, valid proof, eka dtmapratyaya, the single belief in the Self, is the eka-atmapratyaya-sara. And this is in accord with the Vedic text: `The Self alone is to be meditated upon’)
Turiya is not that which is conscious of the inner (subjective) world, nor that which is conscious of the outer (objective) world, nor that which is conscious of both, nor that which is a mass of consciousness. It is not simple consciousness nor is It unconsciousness. It is unperceived, unrelated, incomprehensible, uninferable, unthinkable, and indescribable. The essence of the Consciousness manifesting as the self [in the three states], It is the cessation of all phenomena; It is all peace, all bliss, and non-dual. This is what is known as the Fourth (Turiya). This is Ātman, and this has to be realized.
~Nikhilananda
They consider the fourth quarter as perceiving neither what is inside nor what is outside, nor even both together; not as a mass of perception, neither as perceiving nor as not perceiving; as unseen; as beyond the reach of ordinary transaction; as ungraspable; as without distinguishing marks; as unthinkable; as indescribable; as one whose essence is the perception of itself alone; as the cessation of the visible world; as tranquil; as auspicious; as without a second. That is the self (ātman), and it is that which should be perceived.
~Olivelle
It is not that which is conscious of the internal subjective world nor that which is conscious of the extenal world, nor that which is conscious of both, nor that which is a mass of Consciousness, nor that which is simple Consciousness, nor is it unconscious: It is unseen by any sense organ, beyond empirical dealings, incomprehensible by the mind, uninferable, unthinkable, indescribable, essentially of the Self alone, negation of all phenomena, the peaceful, the auspicious and the non-dual. This is what is known as the fourth (turīya). This is the Ᾱtman and this is to be realised.
~Chinmayananda
The Fourth [Turiya] is not outward-moving consciousness, not consciousness turned inward, not consciousness moving in any direction. It is not a mass of consciousness or all-knowing consciousness. It is not unconscious either. It is beyond perception, beyond all kinds of transactions, ungraspable, uninferable, indescribable and always experienced as the unbroken “I-sense,” free from the world, tranquil, auspicious and non-dual. It is the Self. It is to be known.
~Swartz
He is not knowable by perception, turned inward or outward, nor by both combined. He is neither that which is known, nor that which is not known, nor is He the sum of all that might be known. He cannot be seen, grasped, bargained with. He is undefinable, unthinkable, indescribable. The only proof of His existence is union with Him. The world disappears in Him. He is the peaceful, the good, the one without a second. This is the fourth condition of the Self — the most worthy of all.
~Yeats & Purohit
Not inwardly cognitive (antaḥ-prajña), not outwardly cognitive (bahiḥ-prajña), not both-wise cognitive (ubhayatah-prajña), not a cognition-mass (prajñāna-ghana, not cognitive (prajña), not non-cognitive (a‑prajña), unseen (a‑dṛṣṭa), with which there can be no dealing (a‑vyavahārya), ungraspable (a‑grāhya), having no distinctive mark (a‑lakṣaṇa), non-thinkable (a‑cintya), that cannot be designated (a‑vyapadeśya), the essence of the assurance of which is the state of being one with the Self (ekātmya-pratyaya-sāra), the cessation of development (prapañcopaśama), tranquil (śanta), benign (śiva), without a second (a‑dvaita) — [such] they think is the fourth. He is the Self (Ātman). He should be discerned.
~Hume
The Sages believe that the Fourth which has knowledge neither of the internal (subjective) nor of the external (objective) world, nor simultaneously of the former and the latter, and which, ultimately, is not (even) a unity of integral consciousness, as it is neither conscious nor unconscious – is adṛṣṭa: invisible, avyavahārya: non agent, agrāhya: incomprehensible, alakşana: indefinable, acintya: unthinkable, avyapadesya: indescribable; it is the only pratyayasara: essence of self knowledge, without any trace of manifestation, fullness of peace and bliss devoid of duality: it is the atman and as such it must be known.
~Raphael
People say that the fourth quarter neither perceives outwardly nor inwardly nor both. It is not a mass of cognition- it is neither cognitive nor noncognitive. It is unseen, not open to interaction, ungraspable, without a defining mark, inconceivable, indescribable, the cessation of material proliferation. Tranquil, auspicious, and without a second (advaita). The essence of its certainty is the one Self. That is the Self. That is what is to be known.
~Jones
And a quick transcreation:
Neither outwardly conscious nor inwardly conscious nor both.
Neither integral consciousness nor consciousness itself nor unconsciousness.
Unseen, beyond transaction, inconceivable, uninferable, unthinkable, indescribable.
Essentially one-pointed self-awareness, beyond all phenomena, peaceful, blissful, nondual.
The one Self That is to be known.
~aumdada
