According to Mandukya Upanishad the answer to the question ” Who am I ” is ” Turiya” . The reality is the ” Turiya “
The Upanishad begins with this “Soyam Atma Chatushpada ” i.e. ‘YOU’ have four aspects ( as below ) out of which 3 are false only one is true i.e. “TURIYA“. 

1. ‘I’ is the ‘Waker’ (who is awake ) ——> experiencing the  “Waking World” or “Jagrit Prapanch” in Sanskrit
2. ‘I’ is the Dreamer ( who is dreaming ) —> experiencing the “Dream World”
3. ‘I” is the Sleeper ( who is in deep sleep) —> experiencing sleep blankness or no dream & thought just a sound sleep.
4. Turiya

But we as human being or individuals are not aware of anything like Turiya !! 


What we are aware of is – 

1. You are aware of being a ‘Waker’ experiencing the ‘waking’ world . 

Right now you are reading this blog through your sensory organs and experiencing the knowledge .So you are aware of the waking state.  Your eyes , ears, nose, mind all is awake and you are experiencing this world and the drama going on  around you through your sensory organs . 

2. You are aware of being a ‘Dreamer’ in ‘dream’ world.

Tonight at your home when you sleep and dream , you have certain dream experiences where you see yourself in dream . Then you become a ‘dreamer’ experiencing the dream world with yourself having a dream body , but still you are experiencing the dream !

3. You are in a deep sleep experiencing nothing or sleep blankness

When you are in a deep sleep , there is no dream , it is a simple sound sleep . You do not see any waking world or a dream just simple and plane blankness or Nothing . Daily we experience this ,that in a deep sleep – there is no experience of world , no experience of body and no experience of mind. Even the thought “I am sleeping” is not there. If this thought was there then it is not a deep sleep.