The most important and valued principle of Advaita Vedānta is that everything is divine. Advaita Vedanta achieves this by assigning a relative reality below the single, absolute Brahman. It is a realistic approach too. Though mainly reflects a absolute idealistic outlook, realism has a place in Advaita Vedanta, when it come to the Vyavahārika standpoint. Advaita Vedanta admits the reality of the empirical world from this relative standpoint. Sankara never denied the reality of the external world and its practical validity. He admits its full reality from the empirical standpoint (Vyavaāharika). Sankara says that the relative world is the way to reach the ultimate truth, Brahman. Without travelling through the relative, nobody will reach the ultimate. The relative empirical world is the lower truth and the absolute Brahman is the ultimate truth.
The relative empirical world is said to be essence-less because each and everything in the empirical world depend upon each other. ‘That’, which depend on something ‘other’ for its existence, cannot said to have an essence, in philosophic sense. So the essence-less empirical world is not ultimately real; it depends on the Brahman for its existence. Brahman only is ultimately Real and relative empirical world is indescribable from the viewpoint of this ultimately real Brahman. External world, from the viewpoint of Brahman, is māya or indescribable. Because, it is said to be existing and non-existing at the same time and such things are indescribable. It is also said to be ‘un-real’ elsewhere. Here ‘un-real’ is taken in the ultimate sense. In ultimate sense, only Brahman is real. Everything else is ‘un-real’. ‘Un-real’ does not mean ‘non-existence’.
Empirical world is Maya or indescribable Empirical world is essenceless. So it did not exist by itself. But it is visible to everyone. So, it cannot be termed as non-existing. Because of this complex situation, the nature of empirical world is termed as indescribable. Yet a man, in his life, first came to acquaint with this relative, empirical plane of reality only, not the ultimate plane of reality. External world is the relative plane, that leads him to the ultimate plane of reality.
Ultimate truth is usually assigned as ‘Nirguna Brahman’, devoid of qualities, in Advaita Vedānta. But in relative plane, people assigns personal qualities to this ultimate truth, to bring down it to a lower plane, because ultimate truth is beyond the comprehension of common man having ignorance. But ultimate truth having personal qualities is within the reach of common man. Nirguna Brahman in relative sense, i.e. with personal attributes, is known as ‘Saguna Brahman’. Saguna Brahman is the Brahman with Māya. Man is a Jiva existing in empirical world. Man does not know that he actually belongs to the ultimate plane, but in relative plane, due to Avidya. But when Avidya become extinct by acquiring proper Jnāna (knowledge), man came to knew that he was in relative plane of reality so far and he actually is same as the ultimate reality; not even an inch below or different from the Absolute.
Thus everything in this world is divine in nature. What we need is to realize this in life. When we realize it, then duality will become extinct in us and we will understand that ‘we’ are the same as ‘other’.
The two planes of single reality:-
Because of the difficulty for common man to understand the real nature of ultimate reality, due to avidya, a few philosophical sects assumes two planes or levels for the same reality. The first plane is the ultimate reality itself, which is realizable to those, devoid of avidya. In this plane the ultimate reality will not have qualities. If anything do not have qualities, then that would become beyond comprehension . So this ultimate reality is not comprehensible and thus, indescribable. (Common man can conceive it by a low level definition like ‘sat-chit-ānanda’; real-existing-bliss). This is also known as the high level Brahman. Upanishads use ‘neti, neti’ to indicate its indescribability. This ultimate reality is all everywhere and it is ‘one without a second’. The Advaita Vedānta calls this ultimate reality as ‘Nirguna Brahman’ and madhyamaka buddhists as Prajna and Vasubandhu of vijnānavāda as ‘Vijnāptimātra’.
Anyway, realizing this ultimate reality in life is not easy. Only a man having Brahma-vidya (knowledge about Brahman) and thus devoid of avidya can realize it. After gaining that knowledge he ‘becomes’ it. He becomes jivanmukta in this very life. Yet he has to live till his prārābda karmas get extinct. He will not take birth in the world again after death. He escapes from the clutch of Samsara.
Thus aspirant achieves the plane of ultimate reality. He is in no way below the ultimate, then. His position is in par with the Brahman. He is one with Brahman. In ordinary life, he may not be aware of his original ultimate nature, due to avidya. He may not aware that he is already a liberated being and only need to ‘know’ about his liberated position or divinity. For this ‘knowing’, knowledge about ultimate reality (Brahma-vidya) is necessary. After acquiring this knowledge, he himself becomes Brahman. This is the highest optimistic thing, that man may have ever invented; be one with the absolute reality. Here man is in no way under the absolute even by a small fraction. How such a belief system can be blamed as ‘pessimism’, then?
 Unless otherwise mentioned, Brahman stands for ‘Nirguna Brahman’ throughout this book. Wherever Saguna Brahman is meant, it is stated explicitly.
 Avidya can be whatever which evoke the impression in us that ‘we’ and ‘they’, or whatever makes us think of duality.
 Brahma Vidya is not like ordinary empirical knowledge. This knowledge transcends the realm of senses and intellect.
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