The human being predominantly acts out of ignorance of the true self due to a covering of our perception called the mind. Sri Adi Sankaracharya in Atma Bodha says that owing to this lack of complete knowledge of the self, or rather having only a partial knowledge due to this equipment called the mind, the individual constantly keeps giving an auto-suggestion that he is the doer of actions and the enjoyer or the sufferer of the results.
In very simple words on a daily basis, we copiously put this misunderstanding in words when we say, “I am waking, talking, sleeping, caring, etc.”—it is just the body that is doing all the actions, the mind that is feeling the emotions and the intellect that is thinking the thoughts.
Again, the Acharya proves with a beautiful simile of how we confuse the movement and thoughts of the mind, identify with it and say, “I am doing, I am feeling, I am saying or I am thinking.” The actual situation is: the body is doing it, the mind is feeing something, the sense organ is speaking and the intellect is thinking.
These are the different equipment that are at work and the I or the self has got no role in this process. Yes, we surely and doubtlessly say these sentences, fully believing that what we say is right, when in reality, it is completely wrong.
The example is when someone looks into a pool of water which is gently moving in the wind of the night, the mind is totally identified with the moving water. Yet what we see is only the reflection of the moon and not the moving water. The reflection is very clear to us and without a doubt we say that the moon is twisted and folded in waves and the moon is moving in the water.
In the same way, the self or consciousness that we are in reality is motionless, colourless and quality-less. Yet, we very confidently say that, “I am moving. I am eating. I am suffering.” The reality is that the self is unmoving.
It does not have to eat food to sustain itself. It is always self-sustained. Yet, we say: “I am eating or I feel sleepy.” Just like the moon which is still, the self is non-moving and still. Yet, seeing through the active mind and body, we say, the self, ie. I move, I run, I have won, I have experienced defeat and hence I am extremely sorry and gloomy.
The self is steady. Whatever else that seems to move and act is not the self.