Since, Mandukya Upanishad is the shortest upanishad and also rated as one that alone can grant liberation, I add its text here. This will also help to refer to this text easily whenever required.
The Mandukya Upanishad
Tr. Swami Prabhavananda and Frederick Manchester
All this that we see without is Brahman. This Self that is within is Brahman.
This Self, which is one with OM, has three aspects, and beyond these three, different from them and indefinable–The Fourth.
The first aspect of the Self is the universal person, the collective symbol of created beings, in his physical nature—Vaiswanara. Vaiswanara is awake, and is conscious only of external objects. He has seven members. The heavens are his head, the sun his eyes, air his breath, fire his heart, water his belly, earth his feet, and space his body. He has nineteen instruments of knowledge: five organs of sense, five organs of action, five functions of the breath, together with mind, intellect, heart, and ego. He is the enjoyer of the pleasures of sense.
The second aspect of the Self is the universal person in his mental nature–Taijasa. Taijasa has seven members and nineteen instruments of knowledge. He is dreaming, and is conscious only of his dreams. In this state he is the enjoyer of the subtle impressions in his mind of the deeds he has done in the past.
The third aspect of the Self is the universal person in dreamless sleep–Prajna. Prajna dreams not. He is without desire. As the darkness of night covers the day, and the visible world seems to disappear, so in dreamless sleep the veil of unconsciousness envelops his thought and knowledge, and the subtle impressions of his mind apparently vanish. Since he experiences neither strife nor anxiety, he is said to be blissful, and the experiencer of bliss.
Prajna is the lord of all. He knows all things. He is the dweller in the hearts of all. He is the origin of all. He is the end of all.
The Fourth, say the wise, is not subjective experience, nor objective experience, nor experience intermediate between these two, nor is it a negative condition which is neither consciousness nor unconsciousness. It is not the knowledge of the senses, nor is it relative knowledge, nor yet inferential knowledge. Beyond the senses, beyond the understanding, beyond all expression, is The Fourth. It is pure unitary consciousness, wherein awareness of the world and of multiplicity is completely obliterated. It is ineffable peace. It is the supreme good. It is One without a second. It is the Self. Know it alone!
This Self, beyond all words, is the syllable OM. This syllable, though indivisible, consists of three letters—A-U-M.
Vaiswanara, the Self as the universal person in his physical being, corresponds to the first letter–A. Whosoever knows Vaiswanara obtains what he desires, and becomes the first among men.
Taijasa, the Self as the universal person in his mental being, corresponds to the second letter—U. Taijasa and the letter U both stand in dream, between waking and sleeping. Whosoever knows Taijasa grows in wisdom, and is highly honored.
Prajna, the Self as the universal person in dreamless sleep, corresponds to the third letter—M. He is the origin and the end of all. Whosoever knows Prajna knows all things.
The Fourth, the Self, is OM, the indivisible syllable. This syllable is unutterable, and beyond mind. In it the manifold universe disappears. It is the supreme good–One without a second. Whosoever knows OM, the Self, becomes the Self.
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The Mandukya Upanishad
Tr. Swami Prabhavananda and Frederick Manchester
Om.
With our ears may we hear what is good.
With our eyes may we behold thy righteousness.
Tranquil in body, may we who worship thee find rest.
Om. Peace—peace—peace.
The syllable OM, which is the imperishable Brahman, is the universe. Whatsoever has existed, whatsoever exists, whatsoever shall exist hereafter, is OM. And whatsoever transcends past, present, and future, that also is OM. With our ears may we hear what is good.
With our eyes may we behold thy righteousness.
Tranquil in body, may we who worship thee find rest.
Om. Peace—peace—peace.
All this that we see without is Brahman. This Self that is within is Brahman.
This Self, which is one with OM, has three aspects, and beyond these three, different from them and indefinable–The Fourth.
The first aspect of the Self is the universal person, the collective symbol of created beings, in his physical nature—Vaiswanara. Vaiswanara is awake, and is conscious only of external objects. He has seven members. The heavens are his head, the sun his eyes, air his breath, fire his heart, water his belly, earth his feet, and space his body. He has nineteen instruments of knowledge: five organs of sense, five organs of action, five functions of the breath, together with mind, intellect, heart, and ego. He is the enjoyer of the pleasures of sense.
The second aspect of the Self is the universal person in his mental nature–Taijasa. Taijasa has seven members and nineteen instruments of knowledge. He is dreaming, and is conscious only of his dreams. In this state he is the enjoyer of the subtle impressions in his mind of the deeds he has done in the past.
The third aspect of the Self is the universal person in dreamless sleep–Prajna. Prajna dreams not. He is without desire. As the darkness of night covers the day, and the visible world seems to disappear, so in dreamless sleep the veil of unconsciousness envelops his thought and knowledge, and the subtle impressions of his mind apparently vanish. Since he experiences neither strife nor anxiety, he is said to be blissful, and the experiencer of bliss.
Prajna is the lord of all. He knows all things. He is the dweller in the hearts of all. He is the origin of all. He is the end of all.
The Fourth, say the wise, is not subjective experience, nor objective experience, nor experience intermediate between these two, nor is it a negative condition which is neither consciousness nor unconsciousness. It is not the knowledge of the senses, nor is it relative knowledge, nor yet inferential knowledge. Beyond the senses, beyond the understanding, beyond all expression, is The Fourth. It is pure unitary consciousness, wherein awareness of the world and of multiplicity is completely obliterated. It is ineffable peace. It is the supreme good. It is One without a second. It is the Self. Know it alone!
This Self, beyond all words, is the syllable OM. This syllable, though indivisible, consists of three letters—A-U-M.
Vaiswanara, the Self as the universal person in his physical being, corresponds to the first letter–A. Whosoever knows Vaiswanara obtains what he desires, and becomes the first among men.
Taijasa, the Self as the universal person in his mental being, corresponds to the second letter—U. Taijasa and the letter U both stand in dream, between waking and sleeping. Whosoever knows Taijasa grows in wisdom, and is highly honored.
Prajna, the Self as the universal person in dreamless sleep, corresponds to the third letter—M. He is the origin and the end of all. Whosoever knows Prajna knows all things.
The Fourth, the Self, is OM, the indivisible syllable. This syllable is unutterable, and beyond mind. In it the manifold universe disappears. It is the supreme good–One without a second. Whosoever knows OM, the Self, becomes the Self.
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