Om Namasivaya Nama:
Vignaanamaya Kosa (Intellect Sheath):
The Intellectual Sheath is a modification of Prakruthi (Nature - that is constantly roaming and changing) due to its reflection of light of Chith. It is endowed with function of knowledge and sense organs also identified with body therefore it can't be a Soul!
Ego/Jeeva "I" is beginning-less. Both doer and experiencer are the two main substitute/characteristics of Jeeva. Therefore through these acts, the I-ness is spreading across all activities of human in relative plane. Such Jeeva does everything as per its vasanas (past deeds) and experience the results.
All ups and downs, birth and death are due to these vasanas enjoyed through this intellectual sheath.
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