Aitareya Upaniṣad is part of Aitareya Āraṇyaka which belongs to Ṛgveda. This is one of the most ancient Upaniṣads and is the only Principal Upaniṣad under Ṛgveda. The name Aitareya descends from Ṛṣi Aitareya who is considered as its revealer. It has got three chapters, each of which is divided into sections and then into verses. A verse is identified by its serial number together with the respective section and chapter numbers. This is the tenth Upaniṣad in the series, ‘The Science of Upanishads’.

Being part of a very ancient Āraṇyaka, this Upaniṣad has its expositions in a cryptic language predominantly mythological in nature. This applies especially to narrations regarding origin of beings. We have already studied, in later Upaniṣads, the same topic in a more clarified and rational format. Therefore, there is no point in discussing the presentations made here, in this respect. Aitareya Upaniṣad is specially known for the great declaration (Mahāvākya) it contains: “Prajñānam Brahma”. We have already seen three out of the four Mahāvākyas.


The Upaniṣad opens with a declaration on the oneness and eternalness of Ātmā. Let us see the verse:

आत्मा वा इदमेक एवाग्र आसीत् | नान्यत्किंचन मिषत् | स ईक्षत लोकान्नु सृजा इति ||1.1.1 ||

ātmā vā idameka evāgra āsīt; nānyatkiṃcana miṣat; sa īkṣata lokānnu sṛjā iti. (1.1.1)

Word meaning: ātmā- Ātmā (Ātman); vā- vai – verily; idam- this, here; eka- one; eva- alone; agra- agre – in the beginning; āsīt- was; nānyatkiṃcana- nothing else whatsoever; miṣat- winked, existed; sa- He (Ātmā); īkṣata- thought; lokānnu sṛjā iti- let me create worlds.

Verse meaning: In the beginning, Ātmā alone existed here; nothing else, whatsoever, winked (originated). Ātmā thought, “Let me create the worlds”.

The oneness of Ātmā is an assertion consistently appearing in other Principal Upaniṣads (Bṛhadāraṇyaka 1.4.17, Māṇḍūkya 7 & 12, Śvetāśvatara 6.11, etc.). These Upaniṣads also declare that all beings originated from Ātmā (Bṛhadāraṇyaka 2.4.6, Chāndogya 6.8.7, Kaṭha 5.9 & 5.10, Śvetāśvatara 4.2). Here, Aitareya expresses the same view.

To start with the process of creation, Ātmā envisaged the world and also its protectors such as Agni (Fire), Vāyu (Air), Āditya (Sun), Diśa (directions), Herbs and plants, Moon, Mṛtyu and Water. To these protectors, he planned to provide abodes. At first he employed the form of a cow; but, they did not accept it, as it was found insufficient for them. Then he employed a horse; it too met with rejection. Finally, Ātmā picked up the form of man; fully satisfied, they all acclaimed it as the best. They entered into that form; Agni entered as speech in the mouth, Vāyu as Prāṇa in nostrils, Āditya as sight in eyes, Diśa as hearing in the ears, herbs and plants as hairs in the skin, moon as mind in the heart, Mṛtyu as Apāna in the navel and water as semen in the generative organ. This is what is described in this Upaniṣad about the origin of beings and about allied matters (1.1.2 to 1.1.4 and 1.2.1 to 1.2.4). Here, we may note that the search for abode for protectors culminates in man. This may be taken as an indication of the evolution of beings into the form of man, the forms of cow and horse representing lower rungs in the process. No further discussion is attempted, in view of the reason mentioned in the beginning.

Now, we see in verses 1.3.1 to 1.3.10, a description regarding creation of Annam (food) and the means for its consumption. This too has no philosophical importance and therefore does not warrant a discussion. But, verses 1.3.11 to 1.3.14 contain an esoteric exposition on how Ātmā sustains all the beings and how he comes to be Brahma. Verse 1.3.11 says that having envisaged the worlds, protectors and abodes, Ātmā noticed the inability of all these to exist without him. So he wanted to enter all and to be there always. But, he thought, “If spoken by speech, inhaled by Prāṇa, seen by eyes, heard by ears, touched by skin, thought of by mind, blown out by Apāna, discharged by generative organ, then who am I?” The implication is that he is not one to be spoken by speech, inhaled by Prāṇa, and so on; he is not an object of reach for these protectors. He is their sustainer and therefore, he must be beyond their reach. It follows that he cannot enter the body through any of them.

He therefore made an opening at the top extreme of the head and entered in, through that gate. This opening is known by the name Vidṛti and it is the place of bliss (nāndana). In the body, Ātmā has three places of dwelling which are three states of dreaming (verse 1.3.12). The implication is that Ātmā is seated in the body deep inside the head, which is not reachable by speech, ears, eyes, etc. On reaching him by appropriate means one enjoys bliss. From what we have already seen in other Upaniṣads, we can make out that the seat which finds a mention here is the Heart (Thalamus), the centre of consciousness. We also know that by realising Ātmā, one enjoys bliss (Kaṭha 5.12, Śvetāśvatara 6.12, etc). The three places of dwelling mentioned here are the three states of consciousness, namely, waking, dreaming and deep-sleep, which we have seen in detail in Māṇḍūkya Upaniṣad. All these three states are depicted here as dreaming states, since none of them represents full awakening; the state of full awakening is the fourth state which is independent of the body.

Having established himself in the body, as afore-said, Ātmā saw at first only the forms of beings; he looked if anything else remained to be seen. Then he saw Puruṣa pervading all the beings and recognised this Puruṣa pervading the beings as Brahma; consequently, Ātmā declared, ‘I saw’ (1.3.13). Puruṣa got the name ‘Idandra’ (idam + dra = this I saw) in this manner, but he is indirectly called Indra (1.3.14).

The meaning of this rather veiled description is that Ātmā pervading the beings is Puruṣa; he pervades all, since without him nothing can exist (vide 1.3.11 above). On so pervading, everything naturally becomes Satyam (as stated in verse 2.6.1 of Taittirīya) which is Brahma. Here, when it is declared ‘I saw’, actually Ātmā saw himself pervading the beings. At first, the sight did not go beyond the physical part of the beings, but later it went beyond and saw the pervading entity too. The indication is that in this world, the physical aspects only are easily comprehensible and the sustaining force lies beyond, unreachable to senses. The importance of the name Indra is that he was, in the ancient times, considered to be the Supreme Being, the ultimate power, ruling the world. This underwent change later, when philosophical enquiries progressed further.

We now proceed to the second chapter, wherein it is stated that a person has three births. Let us see which those births are; see verse 2.1.1 which speaks of the first birth:

पुरुषे ह वा अयमादितो गर्भो भवति यदेतद्रेतः तदेतत्सर्वेभ्योഽङ्गेभ्यस्तेजः संभूतम् आत्मन्येवात्मानं बिभर्ति; तद्यदा स्त्रियां सिञ्चति अथैनज्जनयति; तदस्य प्रथमं जन्म || 2.1.1 ||

puruṣe ha vā ayamādito garbho bhavati yadetadretaḥ tadetatsarvebhyoഽṅgebhyastejaḥ saṃbhūtam ātmanyevātmānaṃ bibharti; tadyadā striyāṃ siñcati athainajjanayati; tadasya prathamaṃ janma. (2.1.1)

Word meaning: puruṣe- in man; ha- indeed; vā- verily; ayam- this; ādito- at first; garbhaḥ- conception; bhavati- occurs; yat- which; etat- this; retaḥ- sperm, seminal fluid; tat- that; etat- this; sarvebhyaḥ- of all; aṅgebhyaḥ- of body members; tejaḥ- essence, spirit; saṃbhūtam- combined together, composed of; ātmanyevātmānaṃ- him within himself; bibharti- bears, keeps; yadā- when; striyāṃ- in woman; siñcati- infuses into; atha- then; enajjanayati- delivers it; tadasya- that is his; prathamaṃ- first; janma- birth.

Verse meaning: The first conception (of a person) occurs in man, in the form of sperms (semen) which consists of the essence of all his body members. He bears it within himself (this is the conception). When he infuses his semen into woman, (it is said that) he delivers it; this is the first birth.

The birth mentioned here is not of the man who contributes the sperm, but it applies to all persons in general, man or woman. If, on the contrary, it is the birth of the sperm-producing man, it cannot be his first birth, since he already exists; moreover, we will have to concede then that women do not have births. Therefore, whatever is said in this chapter about three births are to be taken as presenting a general issue, applicable to all, not only to the sperm-giving man. The first birth of the sperm-giving man in a particular case must have happened when his father delivered the sperms into the womb of his mother. Contrary to this, conventional interpretations take the three births as pertaining to the sperm-giving man and consequently they fail to appreciate the message of the Upaniṣad in its right perspective.

In 2.1.2 & 2.1.3, it is said that the sperm infused into the woman becomes a part of her body and therefore it does not hurt her. She fosters it and in return she is fostered by the sperm-owner man. She duly gives birth to the child; it is the second birth of the person. Then, which is the third birth? Let us see it in 2.1.4 which is given below:

सोഽस्यायमात्मा पुण्येभ्यः कर्मभ्यः प्रतिधीयते अथास्यायमितर आत्मा कृतकृत्यो वयोगतः प्रैति, स इतः प्रयन्नेव पुनर्जायते तदस्य तृतीयं जन्म || 2.1.4 ||

soഽsyāyamātmā puṇyebhyaḥ karmabhyaḥ pratidhīyate athāsyāyamitara ātmā kṛtakṛtyo vayogataḥ praiti, sa itaḥ prayanneva punarjāyate tadasya tṛtīyaṃ janma. (2.1.4)

Word meaning: saḥ- he; asya- his; ayam- this; ātmā- body; puṇyebhyaḥ karmabhyaḥ – for virtuous deeds; pratidhīyate- make use of; atha- then; asya- his; ayam- this; itara- the other; ātmā- body; kṛtakṛtyo- accomplished, contented; vayogataḥ- advanced in age; praiti- arrives at, reaches, appears; sa- he; itaḥ- from here (the world of karma); prayanneva- on departing; punarjāyate- is born again; tat- that; asya- his; tṛtīyaṃ- third; janma- birth.

Verse meaning: This body (that which is born as stated in 2.1.3 above) is utilised for doing virtuous deeds; on accomplishing all such deeds, when the body reaches an advanced age, he leaves the world of Karma and is born again. This is his third birth.

The word Ātmā here cannot be taken as indicating the ultimate principle of SAT-CHIT-ĀNANDA, since, Ātmā is only one and is devoid of Karma, whereas the verse says about Ātmā being two and carrying out Karma. The word therefore indicates body only. The two bodies mentioned here are these: the one that is capable of doing Karma and the other that is in advanced age with accomplished deeds. Obviously, these are the two states of the same body. On reaching the latter state, the person leaves the world of Karma and is reborn, which is the third birth; this is the birth into the world of enlightenment. Though each and every person is not going to pass to this final stage in his life time, the Upaniṣad reveals it as a state that a person can possibly attain to. An indirect injunction here is that all able-bodied persons should engage themselves in virtuous deeds and only such persons become eligible to aspire for enlightenment.

A Ṛgveda hymn (4.27.1) cited by the Upaniṣad in this connection supports this concept about third birth. Further explanations are also given in verses 2.1.5 and 2.1.6. The Ṛgveda hymn says about Ṛsi Vāmadeva breaking away the chains of his abode in womb and getting free. See the hymn as quoted in verse 2.1.5:

गर्भे नु सन्नन्वेषामवेदमहं देवानां जनिमानि विश्वा |
शतं मा पुर आयसीररक्षन्नधः श्येनो जवसा निरदीयम् ||

garbhe nu sannanveṣāmavedamahaṃ devānāṃ janimāni viśvā;
śataṃ mā pura āyasīrarakṣannadhaḥ śyeno javasā niradīyam.

Word meaning: garbhe- in the womb; nu- indeed; san- being; anveṣām- searching; avedam- knew; ahaṃ- I; devānāṃ- of devas; janimāni viśvā – all kinds of;
śataṃ- hundered; mā- me; pura- pure- in the dwelling; āyasīrarakṣan- held by iron restraints; adhaḥ- downwards; śyeno- (like a) hawk; javasā- quickly; niradīyam- broke away.

Verse meaning: Indeed, while being in the womb, I knew, by enquiry, all kinds of Devas. (Desirous of their glittering lives, free from restraints) I quickly broke away, (like) a hawk, hundreds of iron-like strong restraints which were holding me down in that dwelling and (became free).

We have seen what the third birth is. Before that birth takes place, there must be a stage, when the person so born was lying in the womb. We know from our understanding of the third birth that this womb is the world of Karmas. It is this womb that Ṛsi Vāmadeva mentions in his Ṛgveda hymn. The iron restraints indicate the formidable bondages of the world of Karmas, the earthly life. Freedom or Mokṣa lies in demolishing these bondages. This is what the revelation of Ṛsi Vāmadeva means. This revelation in Ṛgveda Samhita finds expression in Kaṭha 6.15 and Muṇḍaka 2.2.8, wherein destruction of entanglements in the Heart is mentioned as a means to attain immortality; Muṇḍaka specifically says about perishing of the impressions of Karma.

In verse 2.1.6 Aitareya adds that, by demolishing the worldly bondages as stated in 2.1.5, Ṛsi Vāmadeva contained all the Kāmas in the resultant heavenly world and attained immortality.

In its third chapter Aitareya presents one of the four Mahāvākya(s) declared by Principal Upaniṣads; it is “प्रज्ञानं ब्रह्म (prajñānaṃ brahma)” in verse 3.1.3. (We have already seen the other three Mahāvākyas). The third chapter opens with a question: ”Who or which is that Ātmā whom we meditate upon?” The answer is given thus: ‘Ātmā is He by whom we see or hear or smell scents or utter speech or discern what is sweet and what is not’ (3.1.1). The next verse, 3.1.2 says about Prajñāna. See the verse below:

यदेतत् हृदयं मनश्च, एतत् संज्ञानमाज्ञानं विज्ञानं प्रज्ञानं मेधा दृष्टिर्धृतिर्मतिर्मनीषा जूतिः स्मृतिः सङ्कल्पः क्रतुरसु कामो वश इति, सर्वाण्येवैतानि प्रज्ञानस्य नामधेयानि भवन्ति || 3.1.2 ||

yadetat hṛdayaṃ manaśca, etat saṃjñānamājñānaṃ vijñānaṃ prajñānaṃ medhā dṛṣṭirdhṛtirmatirmanīṣā jūtiḥ smṛtiḥ saṅkalpaḥ kraturasu kāmo vaśa iti, sarvāṇyevaitāni prajñānasya nāmadheyāni bhavanti. (3.1.2)

Word meaning: yadetat- that which is; hṛdayaṃ- Heart; manaḥ- Manas; ca- and; etat- that; saṃjñānam- perception; ājñānaṃ- understanding; vijñānaṃ- worldly knowledge; prajñānaṃ- inner knowledge; medhā- prudence; dṛṣṭiḥ- sight; dhṛti- mental firmness, power of retention in mind; matiḥ- intellect; manīṣā- conception; jūtiḥ- impulse; smṛtiḥ- memory; saṅkalpaḥ- resolve; kratuḥ- determination; asu- reflection; kāmaḥ- wish; vasa- will; iti- so forth, consists of; sarvāṇyevaitāni- all these are verily; prajñānasya- of absolute knowledge; nāmadheyāni bhavanti – are synonyms.

Verse meaning: That which is Heart and Manas consists of perception, understanding, worldly knowledge, inner knowledge, prudence, sight, mental firmness, intellect, conception, impulse, memory, resolve, determination, reflection, wish and will. All these are verily synonyms of absolute knowledge.

We know that Heart is the centre of consciousness in the body; Manas here indicates the whole Antaḥkaraṇa. The phrase, ‘that which is Heart and Manas’, refers to the inner activities of Antaḥkaraṇa undertaken with the help of consciousness from the Heart. This verse says that these activities consist of perception, understanding, etc. It further says that all these can be represented by a single term, ‘Prajñānam’ (प्रज्ञानम्). The word Prajñā (प्रज्ञा) indicates consciousness acting on Antaḥkaraṇa; knowing is the consequence of this action. Prajñānam is an abstraction of all that is gathered by Prajñā in action. Therefore, Prajñānam is said to be absolute knowledge, which means that it is not the knowledge about this or that thing.

Now, we shall see how important Prajñānam is. See verse 3.1.3 below:

एष ब्रह्मा एष इन्द्र एष प्रजापतिः एते सर्वे देवा, इमानि च पञ्चभूतानि – पृथिवी वायुराकाश आपो ज्योतींषि इत्येतानि इमानि च क्षुद्रमिश्राणीव बीजानि इतराणि चेतराणि च अण्डजानि च जारुजानि च स्वेदजानि च उद्भिज्जानि च अश्वा गावः पुरुषा हस्तिनो यत्किंच इदं प्राणि जङ्गमं च पतत्रि च यच्च स्थावरं सर्वं तत् प्रज्ञानेत्रं प्रज्ञाने प्रतिष्ठितं प्रज्ञानेत्रो लोकः प्रज्ञा प्रतिष्ठा प्रज्ञानं ब्रह्म || 3.1.3 ||

eṣa brahmā eṣa indra eṣa prajāpatiḥ ete sarve devā, imāni ca pañcabhūtāni – pṛthivī vāyurākāśa āpo jyotīṃṣi ityetāni imāni ca kṣudramiśrāṇīvabījāni itarāṇi cetarāṇi ca aṇḍajāni ca jārujāni ca svedajāni ca udbhijjāni ca aśvā gāvaḥ puruṣā hastino yatkiṃca idaṃ prāṇi jaṅgamaṃ ca patatri ca yacca sthāvaraṃ sarvaṃ tat prajñānetraṃ prajñāne pratiṣṭhitaṃ prajñānetro lokaḥ prajñā pratiṣṭhā prajñānaṃ brahma. (3.1.3)

Word meaning: eṣa- this; brahmā- Lord Brahmā; eṣa- this; indra- Lord Indra; eṣa- this; prajāpatiḥ- Lord Prajāpatiḥ; ete sarve – all these; devā- Devas; imāni ca pañcabhūtāni – and these pañcabhūtās; ityetāni – such as these; pṛthivī- earth; vāyu- air, ākāśa- space; āpaḥ- water; jyotīṃṣi- fires; imāni ca kṣudramiśrāṇi – small organisms of various kinds; bījāni- seeds; itarāṇi cetarāṇi ca- others and still others; aṇḍajāni- born from eggs; jārujāni- born from the wombs; svedajāni- insects and worms; udbhijjāni- born of shoots; aśvā- horses; gāvaḥ-cows; puruṣā- men; hastinaḥ- elephants; yatkiṃca- whatever; idaṃ- this; prāṇi- breathing; jaṅgamaṃ- moving; patatri-flying; yacca sthāvaraṃ- also that which is not moving; sarvaṃ- all; tat- that; prajñānetraṃ- having Prajñā as eye, led by Prajñā; prajñāne pratiṣṭhitaṃ – established on Prajñānam; prajñānetro lokaḥ – World is led by Prajñā; prajñā pratiṣṭhā – Prajñā is the support; prajñānaṃ brahma – Brahma is Prajñānam.

Verse meaning: Lord Brahma, Lord Indra, Lord Prajāpatiḥ all Devas, all pañcabhūtās, all small organisms of various kinds, seeds of various kinds, beings born from eggs, wombs and shoots, insects and worms, horses, cows, men, elephants and whatever here breathing, moving, flying or not moving – all are led by Prajñā and established on Prajñānam. World is led by Prajñā which is its support also. Brahma is Prajñānam.

We have seen above that Prajñā is the action of consciousness on Antaḥkaraṇa and knowing is the consequence thereof. (Antaḥkaraṇa actually represents the stock of information relating to heredity and physical characteristics together with the physical tools for reading and executing such information. In lower beings and also in initial stages of higher beings, these may be in crude or rudimentary forms). So, Prajñā in essence is consciousness, which in turn represents Ātmā. We have already learnt from other Upaniṣads that universe is ruled and sustained by Ātmā (Bṛhadāraṇyaka 2.1.20, 2.4.6, 2.5.15, 3.7.3 to 3.7.23, 3.8.9, etc, Muṇḍaka 1.1.6, 2.1.1, etc). Here it is said that world is led and supported by Prajñā; the idea expressed is same. In Taittirīya 2.1 we saw that Brahma is Satyam-Jñānam-Anantam. Prajñānam is same as Jñānam; it represents Satyam and Anantam also, since without them Prajñānam cannot exist. So, it follows that Brahma is Prajñānam, as stated in this verse.

The Upaniṣad concludes by declaring that Ṛsi Vāmadeva, by means of this Prajñā, which represents Ātmā, transcended this world and became immortal.

With this, we complete the study of the science of ten Principal Upaniṣads which are renowned as Daśopaniṣads. As stated in the beginning of this series, we will be studying Śvetāśvatara Upaniṣad also, considering its importance in exposition of spiritual knowledge.

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Prior articles in this series:

The Science of the Upanishads – Introduction
The Science of Brihadaranyaka Upanishad
The Science of Chandogya Upanishad
The Science of Ishavasya Upanishad
The Science of Katha Upanishad
The Science of Kena Upanishad
The Science of Mandukya Upanishad
The Science of Mundaka Upanishad
The Science of Prashna Upanishad
The Science of Taittiriya Upanishad
The Science of Aitareya Upanishad
The Science of Shvetashvatara Upanishad
The Science of Upanishads – Conclusion