Uttara Mimamsa/Vedanta Philosophy in the Upasnishads:-
Advaita Vedanta elements in the Upanishads:-
In Advaita Vedanta individual self and supreme self are one and same. Individual self is the reflection of the supreme self on avidya. When this avidya becomes exhausted, individual self become aware of its supreme status and realize the Brahman. In short, as per Advaita Vedanta, we all are already liberated beings. But due to avidya we are not aware of it. When we acquire Brahma-vidya, we will realize our default supreme nature, or the divinity within us. This is the nutshell of Advaita Vedanta.
We can find several passages in the Upanishad collection about the non-dual nature of Atman and Brahman. In fact, though several philosophical ideas are present in the Upanishads, the prominent teaching of the Upanishads is the non-dual, absolute monism of Advaita Vedanta.
In Chandogya upanishad, Uddalaka Aruni teaches his son Svetaketu about the nature of Self as ‘Tat tvam asi’ or ‘You are that’.
“…… O good looking one, of this person when he departs, (the organ of) speech is withdrawn into the mind, mind into the vital force, vital force into the fire, and fire into the supreme deity…… That which is this subtle essence, all this has got That as the Self, That is Truth, That is the Self, Thou art That, O Svetaketu.”
Monism is in full force in the portion of Aruni’s teaching. This same teaching (‘Tat tvam asi’) in a varied form, can be found in the entry gate of the Oracle of Delphi in ancient Greece. There the word inscribed as ‘know thyself’!
Brihadaranyaka Upanishad says that individual self and the supreme self (Brahman) are same, though they may appear to be different in the relative point of view; i.e, in phenomenal world.
“…… The lord of the maya (notions superimposed by ignorance) is perceived as manifold, for to Him are yoked ten organs, nay, hundreds of them. He is the organs; He is ten and thousands – many and infinite. That Brahman is without prior or posterior, without interior or exterior. This self, the perceiver of everything, is Brahman. This is the teaching.”
In Katha Upanisahad, Yama convinces Naciketas that whoever does not realize this non-dual nature of the supreme self, will take birth again and again in this world.
“What indeed is here, is there; what is there, is here likewise. He, who sees as though there is difference here, goes from death to death.”
Yama further instructs Naciketas that how the single ultimate reality, Brahman, appear as multifarious in the phenomenal world, due to the avidya of Jiva. In that way, It is untouched by the limited nature of phenomenal world.
“Just as fire, though one, having entered the world assumes separate forms in respect of different shapes, similarly, the Self inside all beings, though one, assumes a form in respect of each shape; and (yet) it is outside…… As air, though one, having entered into this world, assumes separate forms in respect of different shapes, similarly, the Self inside all beings, though one, assumes a form in respect of each shape; and (yet) It is outside.”
And after realizing the non-dual nature of Brahman, by discerning Its multifarious appearances, Atman becomes one with Brahman.
“Eternal peace is for those – and not for others – who are discriminating and who realize in their hearts Him who – being one, the controller, and the inner self of all – makes a single form multifarious.”
Upanishads are full of monistic ideas which are the basis of Advaita Vedanta philosophy.
The Upanishads and Visishtadvaita / Qualified Monism: –
Upanishadic accounts about the Ultimate Reality are often impersonal, attribute-less. But personified accounts of ultimate reality are also available, occasionally, where qualified monism aptly fit.
In qualified monism, ultimate reality is not devoid of qualities, but with qualities. Devotion is the major element of this spiritual system. In Mundaka Upanishad, the ultimate reality Purusha is mentioned with qualities, which is the usual method of qualified Monism.
“When the seer sees the Purusha – the golden-hued creator, lord, and the source of the inferior Brahman – then the illuminated one completely shakes off both merit and demerit, becomes taintless, and attains absolute equality.”
In numerous other passages also, ultimate reality is ascribed with attributes.
The Upanishads and Dvaita Vedanta: –
Dualism states that individual soul and supreme soul are completely different. They are neither same nor part of one in another. Yet the individual soul depends on the supreme soul for the liberation.
There are verses in the Upanishads which may interpret as pointing to the un-relatedness of individual and supreme soul. A major verse among them is in Mundaka Upanishad; two birds sitting on a tree, one of which is eating the fruits, but the other bird just looking at the first one, dispassionately. This portion has its origin in Rigveda.
“Two birds that are ever associated and have similar names, cling to the same tree. Of course, one eats the fruit of divergent tastes and the other looks on without eating…… On the same tree, the individual soul is drowned (ie stuck), as it were; and so it moans, being worried by its impotence. When it sees thus the other, the adored Lord and His glory, then it becomes liberated from sorrow…… When the seer sees the Purusha – the golden hued, creator, lord, and the source of the inferior Brahman – then the illuminated one completely shakes off both merit and demerit, becomes taintless, and attains absolute equality.”
Here, ‘eating the fruit’ symbolizes that the bird is enjoying his karmaphala for the past actions and is entangled in the riddle of birth-death. Then he sees the other bird, the Supreme self, and began to adore it, and thus coming out of the Samsara. Here individual and supreme soul is different, but individual soul depends on the supreme soul for its liberation. (This same sloka has got other interpretation in advaita and visishtadvaita).
Saivism and Bhakti Marga in the Upanishads:-
Bhakti as a way for liberation (Moksha-marga) existed in India from the time of Rigveda. In the hymns attributed to Varuna, we will feel the ardent devotion of the worshipper. Varuna is described as, the Sun as his eyes, sky as garment and storm as his breath. Also Varuna is harsh to the evildoers and kind if they seek penance.
“Before this Varuna may we be sinless him who shows mercy even to the sinner,
While we are keeping Aditi’s ordinances. Preserve us evermore, ye Gods, with blessings.”
There are numerous other hymns that show the immense worshipping mood of the devotee towards Varuna. S Radhakrishnan has aptly said about the devotee’s mental mood towards Varuna.
“The theism of the Vaishnavas and the Bhagatavas, with its emphasis on bhakti, is to be traced to the Vedic worship of Varuna, with its consciousness of sin and trust in divine forgiveness…”
Among Upanishads, it is Svetasvatara that contains clear cut Bhakti (devotion) elements. Saivism is the predominant feature of Svetasvatara Upanishad.
“Know that nature is surely maya and the Lord of maya is Mahesvara, the supreme lord. This whole world is verily filled by His limbs…… By realizing the one Lord who presides over every womb, in whom everything exists and merges, who bestows boons, and who is self-effulgent and adorable, one attains supreme peace…… May Rudra who is the origin of all deities and the source of all their powers, who is all knowing and the Lord of the entire universe, who initially brought into being Hiranyagarbha, endow us with auspicious (noble) thoughts.”
Siva is the protector and sustainer, and by the unconditional devotion towards him, the worshipper can achieve the final goal of liberation from all bondages.
“Since you are birthless, a person who is frightened (of samsara) takes refuge in You. O Rudra, protect me always with Your face that is turned southwards.”
“Realizing the Siva to be hidden in all beings like the subtle essence of ghee that rises to the surface, knowing that God to be the one entity that encompasses the entire universe, one becomes free of all bondages.”
Devotion theme is present in other texts also, especially in Katha Upanishad. It is suffice to say here that the Bhakti as a way to moksha was prevalent in India from Rigvedic times and it reached in zenith in Srimad Bhagavat Gita.
 Chandogya Upanishad VI.8.6-7
 Brihadaranyaka Upanishad II.v.18
 Katha Upanishad. II.i.10
 Katha Upanishad. II.ii.9-10
 Katha Upanishad. II.ii.12
Mundaka Upanishad. III.i.3
 Mundaka Upanishad. III.i.1-3
 Rigveda VIII.41
 Rigveda VII.87.7
 Indian Philosophy, Vol 1, Page 52
 Svetasvatara Upanishad. IV.10-12
 Svetasvatara Upanishad. IV.21
 Svetasvatara Upanishad. IV.16
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