The Ego - Ahamkara
Actually reflection of the Atman on the sense organs is what expressing everything in us. It is known as "Aabhasa-Thejas",. When this Aabhasa-Thejas reflected through the Antha-Karanas (Viz Mana, Budhi, Ahamkara & Chitham) it is known as Jeeva / Life Energy (Absolute conscious). Therefore, with the presence of Jeeva, all those Antha Karanas becoming active and doing its functions by taking the pride of I and ME through Pancha Karmendriyas and Gjaanendriyas and its subtle functions such as sound, touch, see, taste and smell, and we say I am seeing, I am enjoying, I am touching etc.. this means the Ego who is responding through devises (Upadhi).
Know that it is the Ego that identifying with the body and becomes the doer and experiencer. The same Ego is experiencing the three Avasthas such as Jagrath (Active), Swapna (Dream) & Sushupthi (Deep sleep). When Rajo guna is active, at the time, Ego enjoys Waking stage, during Sathwa, dream stage and while Thamo guna it enjoys deep sleep stage. Therefore, without Ego nothing exists nor you can identify something happening.
When the sense objects are contributing favorable situations we are happy and non favorable situation lead to unhappy and sorrowful. Happiness and miseries are the Dharma of Ego and do not belong to the Atman which is always blissful and never attached to anything. Ever living happiness to be enjoyed only by realizing Atma and its un-attached existence.
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