In these pages, I will put forward a short discussion on the interpretation of the Upanishads with the aim to show that the sutras of the Upanishads are in conformity with the views of a modern Advaita philosophy – that our individual consciousness itself is to be considered as our soul and there is no other independent body other than this to be called ‘soul’.
Here, I will discuss only those sutras which have a relevance for the central idea, that the soul is the individual consciousness only and there is no third entity which we can call the soul.
To recapitulate, briefly there are two ideas:

Traditional interpretation of Advaita philosophy:

Our real identity is an entity called the soul –‘atman’ or ‘jiva’ or ‘purusa’, which sits inside us as the master of our consciousness. All our thoughts, sensations and other products of our consciousness are presented, so to say, to this master and it is then this ‘atman’ or ‘jiva’ or ‘purusa’ which actually sees, hears, thinks, etc. Our consciousness is not ‘alive’ in itself but lights up when this soul is connected to it. So it is this entity, the soul, which is really ‘alive’.
The fundamental importance of this idea is that the soul can survive in itself, apart from consciousness, and this means that it can then transmigrate and take up another consciousness.
The final principle of this idea is that there are three levels of existence, the absolute Brahman at one end, this ‘atman’ or ‘jiva’ in the middle and the body and mind at the other end (body and mind, i.e., matter and consciousness are at the same level as two different strands or dimensions of worldly existence).
The aim of this short analysis is to show that this idea of ‘Atman’ is not the most common definition. This three level idea is brought forward only when reincarnation is discussed.
Sankaracharya strives to make this two level even in these ‘reincarnation’ sutras again by emphasizing that the jiva is the Brahman itself and is non-different from it, and so it is not separate from it. But since he also has to say that it transmigrates, that is, exists apart from both the mind-consciousness and Brahman during the time of migration, this explanation does not work and the conclusion that there are three levels of existence cannot be denied if one accepts a jiva separate from consciousness within the body.

Modern Advaita philosophy:

In this, our individual consciousness itself is our ‘soul’, our ‘atman’ or ‘purusa‘.
Consciousness here is the complex of functions like seeing, hearing, etc, our ego or ‘I‘ness and our thoughts. It is this complex of I-ness-thoughts-sensations,our individual consciousness, which is our soul. The individual acts like ‘seeing’ thinking, etc. cannot be separated out from the complex. There is no independent entity apart from the complex which actually does the seeing, thinking, etc. Of course, we can call this entire complex or individual consciousness as an entity, atman, and then say that it is this individual consciousness/atman which is doing the thinking, seeing, etc. but in this case, the atman is not something apart from the complex itself.
Thus, here there are two levels of existence, the absolute Brahman at one level and the body/mind at the other (matter and consciousness are at the same level as before).
This has the advantage that it is purely logical and scientific. It answers to all the claims that logic and science can demand from it.
When we ask, ‘who am I?’, in modern Advaita, we would say, on the absolute plane I am Brahman and on the relative plane, I am this individual consciousness, this complex of I-ness, thoughts and sensations.
In traditional Advaita, we would say, on the absolute plane I am Brahman and on the relative plane, the atman/jiva which is the witness of this consciousness and which lies beyond this consciousness.
The major part of the Upanishads adheres to this two levels of existence, absolute and relative. It is only when dealing with reincarnation that three levels are considered. Sankaracharya has also repeatedly defined Advaita as defining two levels of existence, the absolute and the relative.
However, there is no doubt that some sutras of the Upanishads explicitly defines a separate atman or jiva which exists apart from consciousness, giving rise to three levels of existence.END=NAM MO SAKYAMUNI BUDDHA.( 3 TIMES ).WORLD VIETNAMESE BUDDHIST ORDER=VIETNAMESE BUDDHIST NUN=GOLDEN LOTUS MONASTERY=THE EIGHTFOLD PATH.THICH CHAN TANH.THE MIND OF ENLIGHTMENT.AUSTRALIA,SYDNEY.7/1/2015.