Upanishads are philosophical-religious texts for Hindus. The word Upanishad is generally translated as to “sit down closely” as one would to listen attentively to instruction by a teacher or other authority figure — which is how the education system worked in ancient India. There are more than a hundred Upanishads, of which ten (sometimes thirteen) are considered to be of prime significance.
The shortest of all Upanishads is Mandukya Upanishad, but it is no less important. In fact, it is among the most important ones. It explains two ideas: one, the AUM (ॐ) symbol, and two, through this symbol, the four states of consciousness. The major theme of the Mandukya Upanishad is an exposition of AUM sound, with a view to training the mind in meditation, for the purpose of achieving freedom, gradually, so that the individual soul is attuned to the Ultimate Reality.
Below is the full text of the Mandukya Upanishad:
On the Greatness of AUM
AUM stands for the supreme Reality.
It is a symbol for what was, what is,
And what shall be, AUM represents also
What lies beyond past, present and future.
Brahman is all, and the Self is Brahman.
This Self has four states of consciousness.
The first is called Vaishvanara, in which
One lives with all the senses turned outward,
Aware only of the external world.
Taijasa is the name of the second,
The dreaming state in which, with the senses
Turned inward, one enacts the impressions
Of past deeds and present desires.
The third state is called Prajna, there is no
Separateness; but the sleeper is not
Conscious of this. Let him become conscious
In Prajna and it will open the door
To the state of abiding joy.
Prajna, all-powerful and all-knowing,
Dwells in the hearts of all as the ruler.
Prajna is the source and end of all.
The fourth is the superconscious state called
Turiya, neither inward nor outward,
Beyond the senses and the intellect,
In which there is none other than the Lord.
He is the supreme goal of life. He is
Infinite peace and love. Realise him!
Turiya is represented by AUM.
Though indivisible, it has three sounds.
A stands for Vaishvanara.
Those who know this,
Through mastery of the senses, obtain
The fruit of their desires and attain greatness.
U indicates Taijasa. Those who know this,
By mastering even their dreams, become
Established in wisdom. In their family
Everyone leads the spiritual life.
M corresponds to Prajna.
Those who know this,
By stilling the mind, find their true stature
And inspire everyone around to grow.
The mantram AUM stands for the supreme state
Of Turiya, without parts, beyond birth
And death, symbol of everlasting joy.
Those who know AUM as the Self become the Self;
Truly they become the Self.
AUM peace, peace, peace.
Kalampedia 